WO2013001310A1 - Macrocyclic compounds and their use as cdk8 inhibitors - Google Patents

Abstract

There is provided compounds of formula I, wherein R¹, R², R³, R⁴, X, Y, Z and ring A have meanings given in the description, and pharmaceutically-acceptable esters, amides, solvates or salts thereof, which compounds are useful in the treatment of diseases in which inhibition of a protein or lipid kinase (e.g. CDK8) is desired and/or required, and particularly in the treatment of cancer or a proliferative disease.

Description

MACROCYCLIC COMPOUNDS AND THEIR USE AS CDK8 INHIBITORS

Field of the Invention This invention relates to novel pharmaceutically-useful compounds, which compounds are useful as kinase inhibitors (such as inhibitors of the CDK8). The compounds are of potential utility in the treatment of diseases such as cancer (particularly colorectal/colon cancer). The invention also relates to the use of such compounds as medicaments, to the use of such compounds for in vitro, in situ and in vivo diagnosis or treatment of mammalian cells (or associated pathological conditions), to pharmaceutical compositions containing them, and to synthetic routes for their production.

Background of the Invention

The malfunctioning of protein kinases (PKs) is the hallmark of numerous diseases. A large share of the oncogenes and proto-oncogenes involved in human cancers code for PKs. The enhanced activities of PKs are also implicated in many non-malignant diseases, such as benign prostate hyperplasia, familial adenomatosis, polyposis, neuro-fibromatosis, psoriasis, vascular smooth cell proliferation associated with atherosclerosis, pulmonary fibrosis, arthritis glomerulonephritis and post-surgical stenosis and restenosis. PKs are also implicated in inflammatory conditions and in the multiplication of viruses and parasites. PKs may also play a major role in the pathogenesis and development of neurodegenerative disorders.

For a general reference to PKs malfunctioning or disregulation see, for instance, Current Opinion in Chemical Biology 1999, 3, 459 - 465. In general, protein kinases are enzymes that mediate intracellular signalling by affecting a phosphoryl transfer from a nucleoside triphosphate to a protein acceptor that is involved in a signalling pathway. These phosphorylation events act as molecular on/off switches that can modulate or regulate the target protein biological function. These phosphorylation events are triggered in response to a variety of extracellular and other stimuli. Many diseases, such as those mentioned above (or hereinafter), are associated with abnormal cellular responses triggered by these types of protein kinase mediated events.

Initiation, progression and completion of the mammalian cell cycle are regulated by various cyclin-dependent kinase (CDK) complexes, which are critical for cell growth. CDK8 is a kinase that is involved in cell cycle control and also implicated in the regulation of transcription.

Tumour development is associated with genetic alteration and deregulation of CDKs and their regulators, suggesting that inhibitors of CDKs may be useful as anti-cancer therapeutics.

Specifically, CDK8 is a kinase that is encoded by the CDK8 gene. It has been found that CDK8 is an oncogene that regulates β-catenin activity (see e.g. Nature (2008) vol. 455 (25) p547-553 by Firestein et al and Cancer Research (2009); 69(20): p7899-7901 by Firestein et al). CDK8 has been identified as a gene that both modulates β-catenin activity and is essential for colon cancer cell proliferation. The gene, which encodes a member of the mediator complex, is located at 13q12.13, which has been found to be a region of recurrent copy number gain in a substantial fraction of colon cancers. The expression of this gene is therefore implicated in the proliferation of colon cancer cells, and hence its suppression may inhibit such proliferation. Given that CDK8 over-expression is characterised by high levels of CDK8 and β-catenin hyperactivity, CDK8 may activate β-catenin and other genes to drive colon cancer progression. Hence, inhibitors of CDK8 may be useful in the treatment of such cancers (by which we include reducing the progression thereof) given that they may inhibit the expression of genes important for oncogenic progression and controlled by CDK8 and/or they may regulate β-catenin activity. The pivotal role of CDKs in co-ordinating and driving the cell cycle in proliferating cells is proven, as are the biochemical pathways they are involved in. Specifically, as discussed above, it has been shown that CDK8 is linked to certain cancers. Given that there is a significant medical need for a targeted treatment of certain cancers, it is clearly of benefit to develop CDK8 inhibitors specifically. For the treatment of cancer, targeted therapies are becoming more important. That is, therapy that has the effect of interfering with specific target molecules that are linked to tumor growth and/or carcinogenesis. Such therapy may be more effective than current treatments (e.g. chemotherapy) and less harmful to normal cells (e.g. because chemotherapy has the potential to kill normal cells as well as cancerous cells). This, and also the fact that targeted therapies may be selective (i.e. it may inhibit a certain targeted molecule more selectively as compared to other molecular targets, e.g. as described hereinafter), may have the benefit of reducing side effects and may also have the benefit that certain specific cancers can be treated (also selectively). The latter may in turn also reduce side effects.

Hence, it is a clear goal of current oncologists to develop targeted therapies (e.g. ones that are selective). In this respect, it should be pointed out that several different molecular targets may exist that are linked to certain diseases (e.g. cancer). However, one simply cannot predict if a therapy (e.g. a small molecule as a therapeutic) that interferes with or inhibits one target molecule could inhibit a different molecular target (be it one that will ultimately have the effect of treating the same disease or a different one).

Targeted therapies (such as CDK8 targeted therapy) could potentially have other advantages over current anti-cancer treatments, for instance because it may not directly interact with DNA (compared to certain known anti-tumour therapies) and should therefore reduce the risk of secondary tumour development.

The listing or discussion of an apparently prior-published document in this specification should not necessarily be taken as an acknowledgement that the document is part of the state of the art or is common general knowledge. Disclosure of the Invention

According to the invention, there is now provided a compound of formula I,

wherein: ring A represents aryl or pyridyl, both of which are optionally substituted by one or more substituents selected from R⁴;

R¹ represents hydrogen or C _-6 alkyl optionally substituted by one or more substituents selected from E¹;

X represents -C(H)= -C(Me)= or -N=;

Y represents a direct bond, -T¹-, -T^-C^alkylene-, -C_1-2alkylene-T³-, -0-N=C(H)- or -d^alkylene-, wherein the alkylene moieties are each independently substituted with one or more substituents selected from R⁵; each T¹, T² and T³ each independently represent a -0-, -C(O)-, -N(R¹⁰)-, -C(0)N(R¹¹)- or -N(R ²)C(0)-; each R², R³, R⁴ and R⁵ independently represent hydrogen or a substituent selected from halo, -CN, R^j1, -OR^j2, -SR^j3, -N(R^j4)R^j5, -C(0)OR^j6 and -N(R^j7)C(0)R^j8;

Rⁱ¹, Rⁱ², R^j3, R'⁴, R^j5, R^j6, R^j7 and R^j8 independently represent hydrogen or (e.g. C_1-4) alkyl optionally substituted by one or more substituents selected from halo and -OR^h; R^h represents hydrogen or C _-4 alkyl optionally substituted by one or more halo atoms;

Z represents -C_3-9alkylene-, -C^alkylene-T^-C^alkylene-, -C(0)N(H)-, -N(H)C(0)-, -C_1-7alkylene-T⁵-, -T⁶-C_1-7alkylene- or -C_1-2alkylene-N(H)-C(0)- d^alkylene-NCH)-, wherein the alkylene moieties are each optionally and independently substituted by one or more substituents selected from E²; each T⁴ represents -0-, -N(R¹³)-, -N(R )-C(0)-, -C(0)-N(R¹⁵)-, -C(O)-, -cycloalkylene-T⁷-, -heterocycloalkylene-T⁷-, -arylene-T⁸- (e.g. -phenylene-) or -heteroarylene-T⁹- (e.g. -pyridylene-); each T⁵ and T⁶ independently represent -C(0)N(H)-, -N(H)C(0)-, -C(O)-, -cycloalkylene-T⁷-, -heterocycloalkylene-T⁷-, -arylene-T⁸- (e.g. -phenylene-) or -heteroarylene-T⁹- (e.g. -pyridylene-); the cycloalkylene, heterocycloalkylene, arylene and heteroarylene moieties are each optionally substituted by one or more substituents independently selected from E³; each T⁷, T⁸ and T⁹ independently represent a direct bond or -C(O)-; each R¹⁰, R¹¹, R¹², R ³, R¹⁴ and R ⁵ independently represent hydrogen or C_1-12 alkyl optionally substituted by one or more substituents selected from E⁴; each E , E², E³ and E⁴ independently represent:

(i) Q⁴;

(ii) C_1-12 alkyl or heterocycloalkyl, both of which are optionally substituted by one or more substituents selected from =0 and Q⁵;

(iii) aryl or heteroaryl, both of which are optionally substituted by one or more substituents selected from Q⁶; any two E¹, E², E³ and/or E⁴ groups (for example on C_1-12 alkyl groups, e.g. when they are attached to the same or adjacent carbon atoms, or, on aromatic groups, when attached to adjacent atoms), may be linked together to form a 3- to 12- membered ring, optionally containing one or more (e.g. one to three) unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from =0 and J¹; each Q⁴, Q⁵ and Q⁶ independently represent, on each occasion when used herein:

halo, -CN, -N(R²⁰)R²¹, -OR²⁰, -C(=Y¹)-R²°, -C(=Y¹)-OR²⁰, -C(=Y¹)N(R ⁰)R²¹, -C(=Y¹)N(R²⁰)-O-R^21a, -OC(=Y¹)-R²⁰, -OC(=Y¹)-OR²⁰, -OC(=Y¹)N(R²⁰)R²¹, -OS(0)₂OR²⁰, -OP(=Y¹)(OR²⁰)(OR²¹), -OP(OR²⁰)(OR²¹), -N(R²²)C(=Y¹)R²¹, -N(R²²)C(=Y¹)OR²¹, -N(R² )C(=Y¹)N(R²⁰)R²¹, -NR²²S(0)₂R²⁰,

-NR²²S(O)₂N(R²⁰)R²¹, -S(O)₂N(R²⁰)R²¹, -SC(=Y )R²⁰, -SC(=Y¹)OR²⁰, -SC(=Y¹)N(R²⁰)R²¹, -S(0)₂R²⁰, -SR²⁰, -S(0)R²⁰, -S(0)₂OR²⁰, C_1-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from =0 and J²), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J³); each Y¹ independently represents, on each occasion when used herein, =0, =S, =NR²³ or =N-CN; each R^21a represents C_1-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from J⁴ and =0), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J⁵); each R²⁰, R²¹, R²² and R²³ independently represent, on each occasion when used herein, hydrogen, C_1-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from J⁴ and =0), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J⁵); or any relevant pair of R²⁰, R² and R²², may (for example, when attached to the same atom, adjacent atom (i.e. 1 ,2-relationship) or to atoms that are two atoms apart, i.e. in a 1,3-relationship) be linked together to form (e.g. along with the requisite nitrogen atom to which they may be attached) a 4- to 20- (e.g. 4- to 12-) membered ring, optionally containing one or more heteroatoms (for example, in addition to those that may already be present, e.g. (a) heteroatom(s) selected from oxygen, nitrogen and sulfur), optionally containing one or more unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from J⁶ and =0; each J¹, J², J³, J⁴, J⁵ and J⁶ independently represents, on each occasion when used herein:

(0 Q⁷;

(ii) C_1-6 alkyl or heterocycloalkyl, both of which are optionally substituted by one or more substituents selected from =0 and Q⁸; each Q⁷ and Q⁸ independently represents, on each occasion when used herein: halo, -CN, -N(R⁵⁰)R⁵¹, -OR⁵⁰, -C(=Y^a)-R⁵⁰, -C(=Y^a)-OR⁵⁰, -C(=Y^a)N(R⁵⁰)R⁵¹, -N(R⁵²)C(=Y^a)R⁵¹, -NR⁵²S(0)₂R⁵⁰, -S(O)₂N(R⁵⁰)R⁵¹, -N(R⁵²)-C(=Y^a)-N(R⁵⁰)R⁵¹, -S(0)₂R⁵⁰, -SR⁵⁰, -S(0)R⁵⁰, C_1-6 alkyl (optionally substituted by one or more fluoro atoms) or heterocyclalkyl (optionally substituted by one or more substituents selected from halo, -OR⁶⁰ and -N(R⁶ )R⁶²); each Y^a independently represents, on each occasion when used herein, =0, =S, =NR⁵³ or =N-CN; each R⁵⁰, R⁵¹, R⁵² and R⁵³ independently represents, on each occasion when used herein, hydrogen or C _-6 alkyl optionally substituted by one or more substituents selected from fluoro, -OR⁶⁰ and -N(R⁶¹)R⁶²; or

any relevant pair of R⁵⁰, R⁵¹ and R⁵² may (for example when attached to the same or adjacent atoms) be linked together to form, a 3- to 8-membered ring, optionally containing one or more heteroatoms (for example, in addition to those that may already be present, heteroatoms selected from oxygen, nitrogen and sulfur), optionally containing one or more unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from =0 and C_1-3 alkyl; R , R and R independently represent hydrogen or C _-6 alkyl optionally substituted by one or more fluoro atoms; or a pharmaceutically acceptable ester, amide, solvate or salt thereof, which compounds, esters, amides, solvates and salts are referred to hereinafter as "the compounds of the invention".

Pharmaceutically-acceptable salts include acid addition salts and base addition salts. Such salts may be formed by conventional means, for example by reaction of a free acid or a free base form of a compound of formula I with one or more equivalents of an appropriate acid or base, optionally in a solvent, or in a medium in which the salt is insoluble, followed by removal of said solvent, or said medium, using standard techniques (e.g. in vacuo, by freeze-drying or by filtration). Salts may also be prepared by exchanging a counter-ion of a compound of the invention in the form of a salt with another counter-ion, for example using a suitable ion exchange resin.

By "pharmaceutically acceptable ester, amide, solvate or salt thereof, we include salts of pharmaceutically acceptable esters or amides, and solvates of pharmaceutically acceptable esters, amides or salts. For instance, pharmaceutically acceptable esters and amides such as those defined herein may be mentioned, as well as pharmaceutically acceptable solvates or salts. Pharmaceutically acceptable esters and amides of the compounds of the invention are also included within the scope of the invention. Pharmaceutically acceptable esters and amides of compounds of the invention may be formed from corresponding compounds that have an appropriate group, for example an acid group, converted to the appropriate ester or amide. For example, pharmaceutically acceptable esters (of carboxylic acids of compounds of the invention) that may be mentioned include optionally substituted C _-6 alkyl, C₅. ₀ aryl and/or C_5-10 aryl-C_1-6 alkyl- esters. Pharmaceutically acceptable amides (of carboxylic acids of compounds of the invention) that may be mentioned include those of the formula -CiO^R^R²², in which R^z and R^z2 independently represent optionally substituted C_1-6 alkyl, C₅.₁₀ aryl, or C₅.₁₀ aryl-C_1-6 alkylene-. Preferably, C_1-6 alkyl groups that may be mentioned in the context of such pharmaceutically acceptable esters and amides are not cyclic, e.g. linear and/or branched. Further compounds of the invention that may be mentioned include carbamate, carboxamido or ureido derivatives, e.g. such derivatives of existing amino functional groups.

For the purposes of this invention, therefore, prodrugs of compounds of the invention are also included within the scope of the invention.

The term "prodrug" of a relevant compound of the invention includes any compound that, following oral or parenteral administration, is metabolised in vivo to form that compound in an experimentally-detectable amount, and within a predetermined time (e.g. within a dosing interval of between 6 and 24 hours (i.e. once to four times daily)). For the avoidance of doubt, the term "parenteral" administration includes all forms of administration other than oral administration.

Prodrugs of compounds of the invention may be prepared by modifying functional groups present on the compound in such a way that the modifications are cleaved, in vivo when such prodrug is administered to a mammalian subject. The modifications typically are achieved by synthesising the parent compound with a prodrug substituent. Prodrugs include compounds of the invention wherein a hydroxyl, amino, sulfhydryl, carboxy or carbonyl group in a compound of the invention is bonded to any group that may be cleaved in vivo to regenerate the free hydroxyl, amino, sulfhydryl, carboxy or carbonyl group, respectively.

Examples of prodrugs include, but are not limited to, esters and carbamates of hydroxy functional groups, esters groups of carboxyl functional groups, N-acyl derivatives and N-Mannich bases. General information on prodrugs may be found e.g. in Bundegaard, H. "Design of Prodrugs" p. 1-92, Elesevier, New York-Oxford (1985).

Compounds of the invention may contain double bonds and may thus exist as E {entgegen) and Z (zusammen) geometric isomers about each individual double bond. Positional isomers may also be embraced by the compounds of the invention. All such isomers (e.g. if a compound of the invention incorporates a double bond or a fused ring, the cis- and trans- forms, are embraced) and mixtures thereof are included within the scope of the invention (e.g. single positional isomers and mixtures of positional isomers may be included within the scope of the invention).

Compounds of the invention may also exhibit tautomerism. All tautomeric forms (or tautomers) and mixtures thereof are included within the scope of the invention. The term "tautomer" or "tautomeric form" refers to structural isomers of different energies which are interconvertible via a low energy barrier. For example, proton tautomers (also known as prototropic tautomers) include interconversions via migration of a proton, such as keto-enol and imine-enamine isomerisations. Valence tautomers include interconversions by reorganisation of some of the bonding electrons.

Compounds of the invention may also contain one or more asymmetric carbon atoms and may therefore exhibit optical and/or diastereoisomerism. Diastereoisomers may be separated using conventional techniques, e.g. chromatography or fractional crystallisation. The various stereoisomers may be isolated by separation of a racemic or other mixture of the compounds using conventional, e.g. fractional crystallisation or HPLC, techniques. Alternatively the desired optical isomers may be made by reaction of the appropriate optically active starting materials under conditions which will not cause racemisation or epimerisation (i.e. a 'chiral pool' method), by reaction of the appropriate starting material with a 'chiral auxiliary' which can subsequently be removed at a suitable stage, by derivatisation (i.e. a resolution, including a dynamic resolution), for example with a homochiral acid followed by separation of the diastereomeric derivatives by conventional means such as chromatography, or by reaction with an appropriate chiral reagent or chiral catalyst all under conditions known to the skilled person.

All stereoisomers (including but not limited to diastereoisomers, enantiomers and atropisomers) and mixtures thereof (e.g. racemic mixtures) are included within the scope of the invention. In the structures shown herein, where the stereochemistry of any particular chiral atom is not specified, then all stereoisomers are contemplated and included as the compounds of the invention. Where stereochemistry is specified by a solid wedge or dashed line representing a particular configuration, then that stereoisomer is so specified and defined.

The compounds of the present invention may exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like, and it is intended that the invention embrace both solvated and unsolvated forms.

The present invention also embraces isotopically-labeled compounds of the present invention which are identical to those recited herein, but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature (or the most abundant one found in nature). All isotopes of any particular atom or element as specified herein are contemplated within the scope of the compounds of the invention. Exemplary isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, chlorine and iodine, such as ²H, ³H, C, ¹³C, ¹ C , ¹³N, ¹⁵0, ¹⁷0, ¹⁸0, ³²P, ³³P, ³⁵S, ¹⁸F, ³⁶CI, ¹²³l, and ¹²⁵l. Certain isotopically-labeled compounds of the present invention (e.g., those labeled with ³H and ¹⁴C) are useful in compound and for substrate tissue distribution assays. Tritiated (³H) and carbon-14 (¹⁴C) isotopes are useful for their ease of preparation and detectability. Further, substitution with heavier isotopes such as deuterium (i.e., ²H may afford certain therapeutic advantages resulting from greater metabolic stability (e.g., increased in vivo half-life or reduced dosage requirements) and hence may be preferred in some circumstances. Positron emitting isotopes such as ¹⁵0, ¹³N, ¹¹C and ¹⁸F are useful for positron emission tomography (PET) studies to examine substrate receptor occupancy. Isotopically labeled compounds of the present invention can generally be prepared by following procedures analogous to those disclosed in schemes and/or the Examples hereinbelow, by substituting an isotopically labeled reagent for a non-isotopically labeled reagent. Unless otherwise specified, C_1-q alkyl groups (where q is the upper limit of the range) defined herein may be straight-chain or, when there is a sufficient number (i.e. a minimum of two or three, as appropriate) of carbon atoms, be branched- chain, and/or cyclic (so forming a C_3-q-cycloalkyl group). Such cycloalkyl groups may be monocyclic or bicyclic and may further be bridged. Further, when there is a sufficient number (i.e. a minimum of four) of carbon atoms, such groups may also be part cyclic. Such alkyl groups may also be saturated or, when there is a sufficient number (i.e. a minimum of two) of carbon atoms, be unsaturated (forming, for example, a C₂._q alkenyl or a C₂-_q alkynyl group).

Unless otherwise stated, the term C _-q alkylene (where q is the upper limit of the range) defined herein may be straight-chain or, when there is a sufficient number of carbon atoms, be saturated or unsaturated (so forming, for example, an alkenylene or alkynylene linker group). However, such C _-q alkylene groups are preferably not branched.

C_3-q cycloalkyl groups (where q is the upper limit of the range) that may be specifically mentioned may be monocyclic or bicyclic alkyl groups, which cycloalkyl groups may further be bridged (so forming, for example, fused ring systems such as three fused cycloalkyl groups). Such cycloalkyl groups may be saturated or unsaturated containing one or more double or triple bonds (forming for example a cycloalkenyl or cycloalkynyl group). Substituents may be attached at any point on the cycloalkyl group. Further, where there is a sufficient number (i.e. a minimum of four) such cycloalkyl groups may also be part cyclic. For the avoidance of doubt, optional substituents may also be other cyclic groups, which may be attached via a single carbon atom common to both rings, so forming a spiro-cycle. The term "halo", when used herein, includes fluoro, chloro, bromo and iodo.

Heterocycloalkyi groups that may be mentioned include non-aromatic monocyclic and bicyclic heterocycloalkyi groups in which at least one (e.g. one to four) of the atoms in the ring system is other than carbon (i.e. a heteroatom), and in which the total number of atoms in the ring system is from five to ten (such as between five and ten). Such heterocycloalkyi groups may also be bridged. Further, such heterocycloalkyi groups may be saturated or unsaturated containing one or more double and/or triple bonds, forming for example a C₂._q heterocycloalkenyl (where q is the upper limit of the range) or a C₇._q heterocycloalkynyl group. C₂._q heterocycloalkyi groups that may be mentioned include 7- azabicyclo[2.2.1 ]heptanyl, 6-azabicyclo[3.1.1 ]heptanyl, 6-azabicyclo[3.2.1 ]- octanyl, 8-azabicyclo-[3.2.1]octanyl, aziridinyl, azetidinyl, dihydropyranyl, dihydropyridyl, dihydropyrrolyl (including 2,5-dihydropyrrolyl), dioxolanyl (including 1 ,3-dioxolanyl), dioxanyl (including 1 ,3-dioxanyl and 1 ,4-dioxanyl), dithianyl (including 1 ,4-dithianyl), dithiolanyl (including 1 ,3-dithiolanyl), imidazolidinyl, imidazolinyl, morpholinyl, 7-oxabicyclo[2.2.1]heptanyl, 6- oxabicyclo-[3.2.1]octanyl, oxetanyl, oxiranyl, piperazinyl, piperidinyl, pyranyl, pyrazolidinyl, pyrrolidinonyl, pyrrolidinyl, pyrrolinyl, quinuclidinyl, sulfolanyl, 3- sulfolenyl, tetrahydropyranyl, tetrahydrofuranyl, tetrahydropyridyl (such as 1 ,2,3,4-tetrahydropyridyl and 1 ,2,3,6-tetrahydropyridyl), thietanyl, thiiranyl, thiolanyl, thiomorpholinyl, trithianyl (including 1 ,3,5-trithianyl), tropanyl and the like. Substituents on heterocycloalkyi groups may, where appropriate, be located on any atom in the ring system including a heteroatom. The point of attachment of heterocycloalkyi groups may be via any atom in the ring system including (where appropriate) a heteroatom (such as a nitrogen atom), or an atom on any fused carbocyclic ring that may be present as part of the ring system. Heterocycloalkyi groups may also be in the N- or S- oxidised form (i.e. those heteroatoms may be substituted with one or two =0 substituents, as appropriate). As stated herein other carbon atoms of the heterocycloalkyi groups mentioned herein may also be substituted by one or more =0 substituents. For the avoidance of doubt, optional substituents may also be other cyclic groups, which may be attached via a single carbon atom common to both rings (so forming a spiro cycle). For the avoidance of doubt, the term "bicyclic" (e.g. when employed in the context of heterocycloalkyi groups) refers to groups in which the second ring of a two-ring system is formed between two adjacent atoms of the first ring. The term "bridged" (e.g. when employed in the context of cycloalkyl or heterocycloalkyi groups) refers to monocyclic or bicyclic groups in which two non-adjacent atoms are linked by either an alkylene or heteroalkylene chain (as appropriate). Aryl groups that may be mentioned include C₆.io aryl groups. Such groups may be monocyclic, bicyclic or tricyclic and have from 6 to 10 (such as between 6 and 10) ring carbon atoms, in which at least one ring is aromatic. C_6-io aryl groups include phenyl, naphthyl and the like, such as 1 ,2,3,4-tetrahydronaphthyl. The point of attachment of aryl groups may be via any atom of the ring system. However, when aryl groups are bicyclic or tricyclic, they are linked to the rest of the molecule via an aromatic ring. For the avoidance of doubt, optional substituents include those defined herein and also include =0 substituents that may be attached to any non-aromatic rings of a polycyclic (e.g. bicyclic) aryl group (however, in an emdodiment, =0 substituents are not included). For the avoidance of doubt, optional substituents may also be other cyclic groups, which may be, when attached to a non-aromatic ring of an aryl group, attached via a single carbon atom common to both rings (so forming a spiro-cycle).

Unless otherwise specified, the term "heteroaryl" when used herein refers to an aromatic group containing one or more heteroatom(s) (e.g. one to four heteroatoms) preferably selected from N, O and S. Heteroaryl groups include those which have from 5 to 10 (such as between 5 and 10) members and may be monocyclic, bicyclic or tricyclic, provided that at least one of the rings is aromatic (so forming, for example, a mono-, bi-, or tricyclic heteroaromatic group). However, when heteroaryl groups are bicyclic or tricyclic, they are linked to the rest of the molecule via an aromatic ring. Heteroaryl groups that may be mentioned include acridinyl, benzimidazolyl, benzodioxanyl, benzodioxepinyl, benzodioxolyl (including 1 ,3-benzodioxolyl), benzofuranyl, benzofurazanyl, benzothiadiazolyl (including 2,1 ,3-benzothiadiazolyl), benzothiazolyl, benzoxadiazolyl (including 2,1 ,3-benzoxadiazolyl), benzoxazinyl (including 3,4- dihydro-2AY-1 ,4-benzoxazinyl), benzoxazolyl, benzomorpholinyl, benzoselena- diazolyl (including 2,1 ,3-benzoselenadiazolyl), benzothienyl, carbazolyl, chromanyl, cinnolinyl, furanyl, imidazolyl, imidazo[1 ,2-a]pyridyl, indazolyl, indolinyl, indolyl, isobenzofuranyl, isochromanyl, isoindolinyl, isoindolyl, isoquinolinyl, isothiaziolyl, isothiochromanyl, isoxazolyl, naphthyridinyl (including 1 ,6-naphthyridinyl or, preferably, 1 ,5-naphthyridinyl and 1 ,8-naphthyridinyl), oxadiazolyl (including 1 ,2,3-oxadiazolyl, 1 ,2,4-oxadiazolyl and 1 ,3,4-oxadiazolyl), oxazolyl, phenazinyl, phenothiazinyl, phthalazinyl, pteridinyl, purinyl, pyranyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, quinazolinyl, quinolinyl, quinolizinyl, quinoxalinyl, tetrahydroisoquinolinyl (including 1 ,2,3,4- tetrahydroisoquinolinyl and 5,6,7,8-tetrahydroisoquinolinyl), tetrahydroquinolinyl (including 1 ,2,3,4-tetrahydroquinolinyl and 5,6,7,8-tetrahydroquinolinyl), tetrazolyl, thiadiazolyl (including 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl and 1 ,3,4-thiadiazolyl), thiazolyl, thiochromanyl, thiophenetyl, thienyl, triazolyl (including 1 ,2,3-triazolyl, 1 ,2,4-triazolyl and 1 ,3,4-triazolyl) and the like. Substituents on heteroaryl groups may, where appropriate, be located on any atom in the ring system including a heteroatom. For the avoidance of doubt, optional substituents include those defined herein and also include =0 substituents that may be attached to any non- aromatic rings of a polycyclic (e.g. bicyclic) heteroaryl group (but, in an embodiment, =0 substituents are not included). For the avoidance of doubt, optional substituents may also be other cyclic groups, which may be, when attached to a non-aromatic ring of a heteroaryl group, attached via a single carbon atom common to both rings (so forming a spiro-cycle). The point of attachment of heteroaryl groups may be via any atom in the ring system including (where appropriate) a heteroatom (such as a nitrogen atom), or an atom on any fused carbocyclic ring that may be present as part of the ring system. Heteroaryl groups may also be in the N- or S- oxidised form.

It may be specifically stated that the heteroaryl group is monocyclic or bicyclic. In the case where it is specified that the heteroaryl is bicyclic, then it may be consist of a five-, six- or seven-mem bered monocyclic ring (e.g. a monocyclic heteroaryl ring) fused with another a five-, six- or seven-membered ring (e.g. a monocyclic aryl or heteroaryl ring).

Heteroatoms that may be mentioned include phosphorus, silicon, boron and, preferably, oxygen, nitrogen and sulphur. Linker groups, for example as defined by Y and Z are specified with hyphens C'-"s) at the respective ends, depicting the points of attachment with the rest of the compound of formula I. For the avoidance of doubt, in relation to the linker groups defined by Z, the first hyphen of the linking moiety is the point at which that moiety links to the requisite -N(R¹)- moiety and the last hyphen depicts the linking point to the Y group. Similarly, for the Y linker group the first hyphen represents the point of attachment to the Z group and the last hyphen represents the point of attachment to ring A.

For the avoidance of doubt, in cases in which the identity of two or more substituents in a compound of the invention may be the same, the actual identities of the respective substituents are not in any way interdependent. For example, in the situation in which there is more than one Q⁴ substituent present, then those Q⁴ substituents may be the same or different. Further, in the case where there are two Q⁴ substituents present, in which one represents -OR²⁰ and the other represents -C(0)-R²⁰, then those R²⁰ groups are not to be regarded as being interdependent.

For the avoidance of doubt, in the instance where cyclic substituents (e.g. cycloalkyi or heterocycloalkyi groups) are present on groups (such as alkyl groups), then those cyclic substituents may be attached to the same carbon atom, so forming for example a spiro-cyclic group.

All individual features (e.g. preferred features) mentioned herein may be taken in isolation or in combination with any other feature (including preferred feature) mentioned herein (hence, preferred features may be taken in conjunction with other preferred features, or independently of them).

The skilled person will appreciate that compounds of the invention that are the subject of this invention include those that are stable. That is, compounds of the invention include those that are sufficiently robust to survive isolation from e.g. a reaction mixture to a useful degree of purity.

For the avoidance of doubt, when a term such as "R¹⁰ to R¹⁵" is employed herein, this will be understood by the skilled person to mean R¹⁰, R¹¹, R ², R¹³, R¹⁴ and R¹⁵, inclusively.

Other preferred compounds of the invention that may be mentioned include those in which:

Ring A represents phenyl or pyridyl (e.g. 3-pyridyl), both of which are optionally substituted by one or more substituents selected from R⁴; preferably, ring A groups have a 1 ,3-linkage to the bicyclic core and Y group; more preferably still ring A represents one of the following groups:

wherein the squiggly lines represent the point of attachment to the bicyclic core and to the Y moiety, and the floating R⁴ substituent represents one or more R⁴ substituents attached to to relevant aromatic ring;

there is two or, preferably, none or one R⁴ substituent present on the A ring;

each R⁴ independently represents represents halo (e.g. fluoro or chloro), -OR^j2, -N(R' )R^j5 or -N(Rⁱ⁷)C(0)Rⁱ⁸;

R^j2, R^j4, R^j5 and R^j7 independently represent hydrogen or C _-4 alkyl (preferably unsubstituted);

R^j8 represents C_1-4 alkyl (preferably unsubstituted, e.g. methyl).

Most preferred compounds of the invention include those in which:

E , E², E³ and E⁴ independently represent, on each occasion when used herein, Q⁴ or C _-6 (e.g. C_1-3) alkyl optionally substituted by one or more substituents selected from =0 and, preferably, Q⁵ (most preferably such E¹ to E⁴ groups represent Q⁴);

each Q⁴, Q⁵ and Q⁶ independently represents, on each occasion when used herein halo, -CN, -N(R²⁰)R²¹, -OR²⁰, -C(=Y )-R²⁰, -C(=Y )-OR²⁰, -C(=Y¹)N(R²⁰)R²¹, -N(R²²)C(=Y¹)R²¹, -N(R²²)C(=Y¹)OR²¹, -NR²²S(0)₂R²⁰, -S(O)₂N(R²⁰)R²¹, -S(0)₂R²⁰, -SR²⁰, -S(0)R²⁰, or C_1-6 alkyl optionally substituted by one or more substituents selected from fluoro;

each Y¹ independently represents, on each occasion when used herein, =0; each R²⁰, R²¹, R²² and R²³ independently represent, on each occasion when used herein, hydrogen or Ci_-3 alkyl optionally substituted by one or more substituents selected from J³ and =0; or

any pair of R²⁰, R²¹ and R²² (e.g. R²⁰ and R² ) may be linked together to form (e.g. when attached to the same nitrogen atom, along with the requisite nitrogen atom to which they are attached) a 4- to 8-membered ring, optionally containing one or more double bonds (e.g. one or two), and which ring may contain a further two or, preferably, one heteroatom (preferably selected from nitrogen and, especially, oxygen), and which ring is optionally substituted by one or more substituents selected from J⁵ and =0;

each J¹, J², J³, J⁴ and J⁵ independently represents, on each occasion when used herein: (i) Q⁷; or (ii) 0_1-6 (e.g. Ci_-3) alkyl optionally substituted by one or more substituents selected from =0 and Q⁸ (more preferably, each J¹, J², J³, J⁴ and J⁵ (e.g. each J¹ and J²) independently represents Q⁷);

each Q⁷ and Q⁸ (e.g. Q⁷) independently represents -N(R⁵⁰)R⁵¹, -OR⁵⁰ or, preferably, halo (e.g. fluoro) or C_1-3 alkyl (e.g. methyl) optionally substituted by one or more fluoro atoms;

each Y^a independently represents =0;

each R⁵⁰, R⁵¹, R⁵² and R⁵³ substituent independently represents, on each occasion when used herein, hydrogen or C_1-6 (e.g. C_1-3) alkyl optionally substituted by one or more substituents selected from fluoro;

R⁶⁰, R⁶¹ and R⁶² independently represent methyl or hydrogen.

Preferred compounds of the invention include those in which:

each E¹, E² E³ and E⁴ independently represent C _-6 (e.g. C_1-3) alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from =0 and, preferably, Q⁵) or E to E⁴ independently (and more preferably) represent Q⁴ (in which E⁴ is preferably halo (e.g. fluoro)); each Q⁴, Q⁵ and Q⁶ (e.g. Q⁴) independently represent halo (e.g fluoro), -C(=Y¹)-OR²⁰ or, more preferably, -N(R²⁰)R²¹, -C(=Y¹)N(R²⁰)R²¹ or -N(R²²)C(=Y )OR²¹;

each Y independently represents =S or, preferably, =0;

R²⁰, R²¹ and R²² (e.g. R²⁰ and R² ) independently represent hydrogen or, preferably, C_1-4 alkyl; or

R²⁰ and R²¹, when attached to the same nitrogen atom are linked together to form a 5- or 6-membered ring, optionally containing a further heteroatom (e.g. nitrogen, or, preferably, oxygen) so forming, e.g. a morpholinyl group;

R²² represents hydrogen.

Other preferred compounds of the invention include those in which:

R¹ represents hydrogen or C_1-3 alkyl optionally substituted by one or more substituents selected from E¹; each R² and R³ independently represent hydrogen or R^j ;

R^j1 represents C_1-2 alkyl (e.g. methyl; preferably unsubstituted);

Y represents -T - or -C_1-2alkylene-T³- each T¹ represents -O- or -N(R¹²)C(0)-;

each T³ preferably represents -0-;

Z represents -C₃.₉alkylene-, -Cvealkylene-T^-d-ealkylene- or -C _-7alkylene-T⁵-; more preferably, Z represents C₅alkylene, -C^alkylene-T'-C^alkylene-, or -C₃alkylene-T⁵-;

each T⁴ represents -0-, -N(R¹³)- or -heterocycloalkylene-T⁷- (in which the net group is preferably a piperidinyl, e.g. 1 ,4-piperidinyl group);

each T⁵ represents -N(H)C(0)-;

T⁷ represents a direct bond or -C(O)-;

each R¹⁰, R¹¹ , R¹², R ³, R¹⁴ and R¹⁵ independently represent hydrogen or C_1-4 alkyl optionally substituted by one or more substituents selected from E⁴;

E¹ represents: (i) C_3-6 cycloalkyl (e.g. cyclopropyl) or a 5- or 6-membered heterocycloalkyl group (e.g. containing one or two heteroatoms, so forming e.g. a morpholinyl group), both of which are optionally substituted by one or more substituents selected from Q⁵ (but which are preferably unsubstituted); or (ii) aryl (e.g. phenyl) optionally substituted by one or more substituents selected from Q⁶; E⁴ represents: (i) Q⁴; (ii) acyclic Ci_-4 alkyl (e.g. methyl), C₃-₆ cycloalkyl (e.g. cyclopropyl) or a 4-, 5- or 6-membered heterocycloalkyl group (e.g. containing one or two heteroatoms, so forming e.g. a morpholinyl, azetidinyl or piperidinyl group), both of which are optionally substituted by one or more substituents selected from Q⁵ (but which are preferably unsubstituted); or (iii) aryl (e.g. phenyl) optionally substituted by one or more substituents selected from Q⁶;

Q⁴ represents -N(R²⁰)R²¹ or -OR²⁰;

Q⁶ represents halo (e.g. chloro or fluoro);

R²⁰ and R²¹ independently represent hydrogen or C _-3 alkyl optionally substituted by one or more substituents selected from J⁴;

J⁴ represents Q⁷;

Q⁷ represents -OR⁵⁰;

R⁵⁰ represents hydrogen or preferably C_1-2 alkyl. Particular compounds of the invention include compounds of formula I,

wherein: ring A represents phenyl optionally substituted by one or more substituents selected from R⁴; R¹ represents hydrogen or C_1-2 alkyl optionally substituted by one or more substituents selected from E¹;

X represents -C(H)= or -C(Me)=; Y represents -T - or -C _-2alkylene-, wherein the alkylene moieties are each independently substituted with one or more substituents selected from R⁵; T¹ represents -0-, -C(0)N(R¹¹)- or -N(R¹²)C(0)-; each R², R³, R⁴ and R⁵ independently represents hydrogen or a substituent selected from halo, R^j1, -OR'², -N(R^j4)R^j5, and -N(Rⁱ⁷)C(0)R^j8; R^j1, R^j2, R^j4, R'⁵, R^j7 and R^j8 independently represent hydrogen or C_1-2 alkyl;

Z represents -C₃.₉alkylene-, or -C^alkylene-T^C^alkylene-; each T⁴ represents -0-, -N(R¹³)-, -N(R¹ )-C(0)-, -C(0)-N(R¹⁵)-, or -heterocycloalkylene-T⁷-;

T⁷ represents a direct bond or -C(O)-;

Each R¹¹, R¹³, R ⁴ and R¹⁵ independently represents hydrogen or C_1-2 alkyl optionally substituted by one or more substituents selected from E⁴; each E¹ and E⁴ independently represents:

(i) Q⁴;

(ii) alkyl or heterocycloalkyl;

(iii) aryl or heteroaryl, both of which are optionally substituted by one or more substituents selected from Q⁶; each Q⁴ and Q⁶ independently represents, on each occasion when used herein: halo, -N(R²⁰)R²¹, or -OR²⁰; each R²⁰ and R²¹ independently represents, on each occasion when used herein, hydrogen, or C _-2 alkyl optionally substituted by one or more substituents selected from J⁴;

J⁴ represents -O-methyl; or a pharmaceutically acceptable ester, amide, solvate or salt thereof.

Particular compounds of the invention include compounds of formula I,

wherein: ring A represents phenyl optionally substituted by one or more substituents selected from R⁴;

R¹ represents hydrogen or C_1-2 alkyl optionally substituted by one or more substituents selected from E ;

X represents -C(H)=;

Y represents -0-, or -N(R¹²)C(0)-; each R², R³, R⁴ independently represents hydrogen or a substituent selected from halo;

Z represents -C₄.₇alkylene-, or -C-|.₂alkylene-T⁴-C _-2alkylene-;

T⁴ represents -0-, -N(R¹³)- or -heterocycloalkylene-T⁷-; T⁷ represents a direct bond;

R¹³ represents hydrogen or methyl optionally substituted by one or more substituents selected from E⁴; each E¹ and E⁴ independently represents C _-4 alkyl, heterocycloalkyl, aryl or heteroaryl; or a pharmaceutically acceptable ester, amide, solvate or salt thereof. Particularly preferred compounds of the invention include those of the examples described hereinafter.

Compounds of the invention may be made in accordance with techniques that are well known to those skilled in the art, for example as described hereinafter. According to a further aspect of the invention there is provided a process for the preparation of a compound of formula I which process comprises:

(i) reaction of a compound of formula II in which Z represents: -C ealkylene-T⁴- C_1-6 alkylene, -C(0)N(H)-, -N(H)C(0)-, -C_1-7alkylene-T⁵-, -T⁶-d.₇alkylene- or -C_1-2alkylene-N(H)-C(0)-C_1-2alkylene-N(H)-, in which T⁴ represents -N(R¹⁴)-C(0)- or -C(0)-N(R¹⁵)-; and T⁵ and T⁶ independently represent -C(0)N(H)- or -N(H)C(0)-, may be prepared by intramolecular reaction of a compound of formula II,

wherein Z¹ represents -C_1-6alkylene-C(0)OH, -Ci_-6alkylene-N(R¹ )H, -C(0)OH, -NH₂, -C_1-7alkylene-C(0)OH, -C_1-7alkylene-NH₂, -C^alkylene-NHz, and Z² respectively represents HN(R¹⁵)-C_1-6alkylene-, HO(0)C-C_1-6alkylene-, H₂N-, HO(0)C-, H₂N-, HO(0)C- and HO(0)C-C_1-2alkylene-N(H)- (or derivatives thereof, such as carboxylic acid ester derivatives), and R¹ , R², R³, R⁴, X, Y and ring A are as hereinbefore defined, which reaction is an amide coupling, which may be performed under standard reaction conditions, for instance the reaction may be performed in the presence of a suitable coupling reagent (e.g. 1 ,1 '- carbonyldiimidazole, Λ/,Λ/'-dicyclohexylcarbodiimide, 1 -(3-dimethylaminopropyl)-3- ethylcarbodiimide (or hydrochloride thereof), Λ/,Λ/'-disuccinimidyl carbonate, benzotriazol-1 -yloxytris(dimethylamino)phosphonium hexafluorophosphate, 2- (1 H-benzotriazol-1-yl)- ,1 ,3,3-tetramethyluronium hexa-fluorophosphate, benzotriazol-1 -yloxytris-pyrrolidinophosphonium hexafluoro-phosphate, bromo- tris-pyrrolidinophosponium hexafluorophosphate, 2-(1 /-/-benzotriazol-1 -yl)-1 , 1 ,3,3- tetramethyluronium tetra-fluorocarbonate, 1 -cyclohexyl-carbodiimide-3- propyloxymethyl polystyrene, 0-(7-azabenzotriazol-1-yl)-/V,/\/,A/^',/N/ ^'- tetramethyluronium hexafluorophosphate, O-benzotriazol-l-yl-Λ/,Λ/,Λ/',Λ - tetramethyluronium tetrafluoroborate and/or 1 -hydroxy-7-azabenzotriazole), optionally in the presence of a suitable base (e.g. sodium hydride, sodium bicarbonate, potassium carbonate, pyridine, triethylamine, dimethylaminopyridine, diisopropylamine, diisopropylethylamine, sodium hydroxide, potassium tert- butoxide, dimethylaminopyridine and/or lithium diisopropylamide (or variants thereof), an appropriate solvent (e.g. tetrahydrofuran, pyridine, toluene, dichloromethane, chloroform, acetonitrile, dimethylformamide, trifluoromethylbenzene, dioxane or triethylamine) and a further additive (e.g. 1- hydroxybenzotriazole hydrate). Preferred amide coupling reaction conditions include reaction in the presence of a coupling reagent HATU, PyBOP and/or HOAt, in the presence of a base (preferably DIPEA and, optionally D AP) and solvent (preferably DMF). In the case when reaction is performed on an ester functional group (e.g. -C(0)OCH₃ or -C(0)OCH₂CH₃), in the presence of e.g. trimethylaluminium, or, alternatively the -C(0)OH group may first be activated to the corresponding acyl halide (e.g -C(0)CI, by treatment with oxalyl chloride, thionyl chloride, phosphorous pentachloride, phosphorous oxychloride, or the like), under standard conditions known to those skilled in the art (e.g. optionally in the presence of a suitable solvent, suitable base and/or in an inert atmosphere);

(ii) compounds of formula I in which Z represents:

alkylene, in which T⁴ represents -O- or -N(R¹³)-, may be prepared by intramolecular reaction of a compound of formula III,

wherein Z³ represents -d.₆alkylene-OH, -C_1-6alkylene-N(R¹³)H or -C_1-6alkylene-L^x (in which L^x is a suitable leaving group, such as chloro, bromo, iodo or a sulfonate group such as -OS(0)₂CF₃, -OS(0)₂CH₃ or -OS(0)₂PhMe), and Z⁴ represents L^y-Ci_-6alkylene-, HO-C _-6alkylene- or H(R¹³)N-Ci.₆alkylene (as appropriate), and R¹, R², R³, R⁴, X, Y and ring A are as hereinbefore defined, which reaction may be peformed under standard nucleophilic substitution reaction conditions, for instance in the presence of a suitable base (e.g. sodium hydride, sodium bicarbonate, potassium carbonate, pyrrolidinopyridine, pyridine, triethylamine, tributylamine, trimethylamine, dimethylaminopyridine, diisopropylamine, diisopropylethylamine, 1 ,8-diazabicyclo[5.4.0]undec-7-ene, sodium hydroxide, N- ethyldiisopropylamine, A/-(methylpolystyrene)-4-(methylamino)pyridine, potassium bis(trimethylsilyl)amide, sodium bis(trimethylsilyl)amide, potassium tert- butoxide, lithium diisopropylamide, lithium 2,2,6,6-tetramethylpiperidine or mixtures thereof) and an appropriate solvent (e.g. tetrahydrofuran, pyridine, toluene, dichloromethane, chloroform, acetonitrile, dimethylformamide, trifluoromethylbenzene, dioxane or triethylamine). However, if there is a L^x or L^y group directly attached to an aromatic ring, and reaction is performed with a nucleophilic -OH or -N(R ²)H moiety, the reaction may be performed in the presence of an appropriate metal catalyst (or a salt or complex thereof) such as Cu, Cu(OAc)₂, Cul (or Cul/diamine complex), copper tris(triphenyl- phosphine)bromide, Pd(OAc)₂, tris(dibenzylideneacetone)-dipalladium(0) (Pd₂(dba)₃) or NiCI₂ and an optional additive such as Ph₃P, 2,2'- bis(diphenylphosphino)-1 ,1'-binaphthyl, xantphos, Nal or an appropriate crown ether such as 18-crown-6-benzene, in the presence of an appropriate base such as NaH, Et₃N, pyridine, /V,/V-dimethylethylenediamine, Na₂C0₃, K₂C0₃, K₃P0₄, Cs₂C0₃, f-BuONa or i-BuOK (or a mixture thereof, optionally in the presence of 4A molecular sieves), in a suitable solvent (e.g. dichloromethane, dioxane, toluene, ethanol, isopropanol, dimethylformamide, ethylene glycol, ethylene glycol dimethyl ether, water, dimethylsulfoxide, acetonitrile, dimethylacetamide, /V-methylpyrrolidinone, tetrahydrofuran or a mixture thereof). This reaction may be carried out under microwave irradiation reaction conditions or, alternatively, the reaction may be performed in the absence of other reagents such as catalyst, base and even solvent;

(iii) for compounds of formula I in which Y represents -T¹- or -T²-Ci_-2alkylene-, in which T¹ and T² independently represent -O- or -N(R¹⁰)- and Z represents -C_3-9alkylene-, -C^alkylene-^'T'-C^alkylene-, -N(H)C(0)- or -T⁶-C_1-7alkylene-, may be prepared by intramolecular reaction of a compound of formula IV,

wherein Y^x represents HO-, HN(R¹⁰)-, HO-C_1-2alkylene- or HN(R¹⁰)-C_1-2alkylene-, Z⁵ represents -C₃.₉alkylene-L^x, -C .₆alkylene-T⁴-C₁.₆alkylene-L , -N(H)C(0)-L^x or -^"T-d.yalkylene-L , and L^x (a suitable leaving group), R¹, R², R³, R⁴, X, Y and ring A are as hereinbefore defined, under reaction conditions such as those described hereinbefore in respect of process step (ii);

(iv) for compounds of formula I in which Y represents -T¹- or -T²-C_1-2alkylene- in which T and T² independently represent -C(0)N(R¹¹)- or -N(R¹²)C(0)- and Z represents -C₃.₉alkylene-, -d-₆alkylene-T⁴-d-₆alkylene- or -T^-d-zalkylene-, may be prepared by intramolecular reaction of a compound of formula V,

wherein Y^y represents HO(0)C-, HN(R¹¹)-, HO(0)C-C_1-2alkylene- or HN(R¹¹)-C_1-2- alkylene-, Z⁶ represents -C_3-9alkylene-N(R¹¹)H, -C₃.₉alkylene-C(0)OH, -d-₆alkylene-T -d-6alkylene-N(R¹¹)H or -d-₆alkylene-T -d-₆alkylene-C(0)OH, and R¹, R², R³, R⁴, X, Y and ring A are as hereinbefore defined, under reaction conditions such as those described hereinbefore in respect of process step (i);

(v) compounds of formula I in which R¹⁰, R¹ , R¹², R¹³, R ⁴ and/or R¹⁵ represent optionally substituted Ci_ ₂ alkyl, may be prepared by reaction of a corresponding compound of formula I in which R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and/or R¹⁵ represent hydrogen, with a compound of formula VI, L¹-R 10-15 VI wherein R^{10" 5} represents R¹⁰, R¹¹, R¹², R¹³, R ⁴ or R ⁵ (as appropriate/required) and L¹ represents a suitable leaving group as defined for L (e.g. under standard alkylation reaction conditions, such as reaction in the presence of base and solvent, e.g. under conditions such as those mentioned in step (ii) above), or with a compound of formula VII,

H(0)C-R 10a-15a VII wherein R^10a"15a represents Ci_-5 alkyl optionally substituted by one or more halo atoms, under reductive amination reaction conditions (for example in the presence of a chemoselective reducing agent such as sodium triacetoxyborohydride or sodium cyanoborohydride, or alternatively, as a two-step process included condensation and then reduction, which reduction step in this instance may be performed in the presence of a stronger reducing agent such as sodium borohydride or LiAIH₄); (vi) compounds of formula I containing a -N(R¹⁰)-CH₂- or -N(R¹³)-CH₂- moiety (e.g. when Z contains a -N(R ³)-CH₂- moiety or Y contains a -N(R ⁰)-CH₂- moiety) may be prepared by reduction of a corresponding compound of formula I containing a -C(0)N(R¹¹), -N(R¹²)C(0)-, -N(R¹⁴)C(0)- or -C(0)N(R¹⁵) moiety (e.g. when Z contains a -N(R¹⁴)-C(0)- moiety), for example in the presence of appropriate reduction reaction conditions, e.g. in the presence of a chemoselective reducing agent such as LiAIH₄.

Compounds of formula II, III, IV and V may be prepared by reaction of a compound of formula VIII,

wherein L² represents a suitable leaving group, such as such as iodo, bromo, chloro, a sulfonate group (e.g. -OS(0)₂CF₃, -OS(0)₂CH₃ or -OS(0)₂PhMe), or a sulfide group (e.g. -S-C_1-6 alkyl, such as -SCH₃), Z^x represents Z Z³, Z⁵ or Z⁶ (depending on whether compound of formula II, III, IV or V is being prepared) and R¹, R², R³ and ring X are as hereinbefore defined, with a compound of formula IX,

wherein Y^z represents Ζ²-Υ-, Ζ⁴-Υ-, Y - or Y^y-, L³ represents a suitable group, such as -B(OH)₂, -B(OR^wx)₂ or -Sn^),, in which each R^wx independently represents a C_1-6 alkyl group, or, in the case of -B(OR^wx)₂, the respective R^wx groups may be linked together to form a 4- to 6-membered cyclic group (such as a 4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2-yl group), thereby forming e.g. a pinacolato boronate ester group, (or L³ may represent iodo, bromo or chloro, provided that L² and L³ are mutually compatible), and R⁴ and ring A are as hereinbefore defined, under standard reaction conditions, for instance in the presence of a suitable catalyst system, e.g. a metal (or a salt or complex thereof) such as Pd, Cul, Pd/C, PdCI₂, Pd(OAc)₂, Pd(Ph₃P)₂CI₂, Pd(Ph₃P)₄ (i.e. palladium tetrakistriphenylphosphine), Pd₂(dba)₃ and/or NiCI₂ (preferred catalysts include palladium) and a ligand such as PdCI₂(dppf).DCM, f-Bu₃P, (C₆Hii)₃P, Ph₃P, AsPh₃, P(o-Tol)₃, 1 ,2-bis(diphenylphosphino)ethane, 2,2'-bis(di-terf-butyl- phosphino)-1 , 1 '-biphenyl, 2,2'-bis(diphenylphosphino)-1 , 1 '-bi-naphthyl, 1 , 1 '- bis(diphenyl-phosphino-ferrocene), 1 ,3-bis(diphenylphosphino)propane, xantphos, or a mixture thereof (preferred ligands include PdCI₂(dppf).DCM), together with a suitable base such as, Na₂C0₃, K₃P0₄, Cs₂C0₃, NaOH, KOH, K₂C0₃, CsF, Et₃N, (/-Pr)₂NEt, f-BuONa or f-BuOK (or mixtures thereof; preferred bases include Na₂C0₃ and K₂C0₃) in a suitable solvent such as dioxane, toluene, ethanol, dimethylformamide, dimethoxyethane, ethylene glycol dimethyl ether, water, dimethylsulfoxide, acetonitrile, dimethylacetamide, /V-methylpyrrolidinone, tetrahydrofuran or mixtures thereof. When L³ represents a sulfide (e.g. -SCH₃), then an additive such as CuMeSal (copper(l) 3-methylsalicylate) or CuTC (copper(l)thiophene-2-carboxylate) may also be employed. The reaction may be carried out for example at room temperature or above (e.g. at a high temperature such as at about the reflux temperature of the solvent system). Alternative reaction conditions include microwave irradiation conditions, for example at elevated temperature, e.g. of about 130°C.

Alternatively, compounds of formula II, III, IV or V may be prepared by reaction of a compound of formula X,

wherein L represents a suitable leaving group such as one hereinbefore defined for L², and R¹, R², R³, R⁴, X, Y^z and ring A are as hereinbefore defined, with a compound of formula XI, H(R¹)N-Z^X XI wherein R and Z^x are as hereinbefore defined, under standard coupling reaction conditions, for instance in the presence of an appropriate metal catalyst (or a salt or complex thereof) such as Cu, Cu(OAc)₂, Cul (or Cul/diamine complex), copper tris(triphenyl-phosphine)bromide, Pd(OAc)₂, tris(dibenzylideneacetone)- dipalladium(O) (Pd₂(dba)₃) or NiCI₂ and an optional additive such as Ph₃P, 2,2'- bis(diphenylphosphino)-1 ,1'-binaphthyl, xantphos, Nal or an appropriate crown ether such as 18-crown-6-benzene, in the presence of an appropriate base such as NaH, Et₃N, pyridine, /,/V-dimethylethylenediamine, Na₂C0_3l K₂C0₃, K₃P0₄, Cs₂C0₃, f-BuONa or f-BuOK (or a mixture thereof, optionally in the presence of 4A molecular sieves), in a suitable solvent (e.g. dichloromethane, dioxane, toluene, ethanol, isopropanol, dimethylformamide, ethylene glycol, ethylene glycol dimethyl ether, water, dimethylsulfoxide, acetonitrile, dimethylacetamide, A/-methylpyrrolidinone, tetrahydrofuran or a mixture thereof). This reaction may be carried out under microwave irradiation reaction conditions or, alternatively, the reaction may be performed in the absence of other reagents such as catalyst, base and even solvent.

Compounds of formula II, III, IV or V may be prepared by reaction of a compound of formula XII,

or a mono-protected amino derivative thereof, wherein R², R³, R⁴, X, Y^z and ring A are as hereinbefore defined, with a compound of formula XIII

L -Z^x XIII wherein L⁴ represents a suitable leaving group, such as one hereinbefore defined for L^x (e.g. chloro, bromo or iodo) and Z^x is as hereinbefore defined, under standard reaction conditions such as those hereinbefore described in respect of process step (ii) above.

Compounds of formula VIII may be prepared by reaction of a compound of formula XIV,

wherein L², L^2a, R² and R³ are as hereinbefore defined, with a compound of formula XI as hereinbefore defined, under reaction conditions such as those hereinbefore described in respect of preparation of compounds of formula II, III, IV and V (reaction of compounds X and XI). Compounds of formula II, III, IV, V, X and XII may be prepared by reaction of a compound of formula XV,

wherein X^z represents (R¹)(Z¹)N-, (R )(Z³)N-, (R )(Z⁵)N-, (R )(Z⁶)N-, L^2a or H₂N- (or mono-protected derivative thereof) (depending on the compound to be prepared, i.e. if it is a compound of formula II, III, IV, V, X or XII), L⁵ represents a suitable leaving group such as one hereinbefore defined for L², and R², R³ and X are as hereinbefore defined, with a compound of formula XVI,

wherein L⁶ represents a suitable group such as one hereinbefore defined for L³, and Y^z, R⁴ and ring A are as hereinbefore defined, for example under reaction conditions such as those described hereinbefore in respect of compounds of formula II, III, IV or V (reaction between compounds VIII and IX). Compounds containing a halo atom (e.g. on an aromatic ring), may be prepared by reaction of a corresponding compound in hydrogen is present, with a source of halide ions, for instance an electrophile that provides a source of iodide ions includes iodine, diiodoethane, diiodotetrachloroethane or, preferably, N- iodosuccinimide, a source of bromide ions includes /V-bromosuccinimide and bromine, and a source of chloride ions includes /V-chlorosuccinimide, chlorine and iodine monochloride.

Compounds containing a -OH moiety (e.g. on an alkyl or alkylene linker group) may be converted to a suitable leaving group, e.g. by conversion to a corresponding bromo or iodo moiety (e.g. by reaction in the presence of HBr or l₂/Ph₃P) or by conversion to a sulfonate (e.g. by reaction with a sulfonyl chloride).

Certain other intermediate compounds may also be commercially available, known in the literature, or may be obtained either by analogy with the processes described herein, or by conventional synthetic procedures, in accordance with standard techniques, from available starting materials using appropriate reagents and reaction conditions. Further, the skilled person will appreciate that where reactions to introduce the "-N(R¹)Z-" moiety of compounds of formula I is described, similar reactions may be performed to introduce the "ring A" moiety in compounds of formula I and vice versa. Further, processes to prepare compounds of formula I may be described in the literature, for example in:

Werber.G. et al.; J. Heterocycl. Chem.; EN; 14; 1977; 823-827;

Andanappa K. Gadad et al. Bioorg. Med. Chem. 2004, 12, 5651-5659;

Paul Heinz et al. Monatshefte fur Chemie, 1977, 108, 665-680;

M.A. El-Sherbeny et al. Boll. Chim. Farm. 1997, 136, 253-256;

Nicolaou, K. C; Bulger, P. G.; Sarlah, D. Angew. Chem. Int. Ed. 2005, 44, 2-49;

Bretonnet et al. J. Med. Chem. 2007, 50, 1872 ;

Asuncion Marin et al. Farmaco 1992, 47 (1), 63-75;

Severinsen, R. et al. Tetrahedron 2005, 61, 5565-5575;

Nicolaou, K. C; Bulger, P. G.; Sarlah, D. Angew. Chem. Int. Ed. 2005, 44, 2-49;

M. Kuwahara et al., Chem. Pharm Bull., 1996, 44, 122;

Wipf, P.; Jung, J.-K. J. Org. Chem. 2000, 65(20), 6319-6337;

Shintani, R.; Okamoto, K. Org. Lett. 2005, 7 (21), 4757-4759;

Nicolaou, K. C; Bulger, P. G.; Sarlah, D. Angew. Chem. Int. Ed. 2005, 44, 2-49;

J. Kobe et al., Tetrahedron, 1968, 24, 239 ;

P.F. Fabio, A.F. Lanzilotti and S.A. Lang, Journal of Labelled Compounds and Pharmaceuticals, 1978, 15, 407;

F.D. Bellamy and K. Ou, Tetrahedron Lett, 1985, 25, 839;

M. Kuwahara et al., Chem. Pharm Bull., 996, 44, 122;

A.F. Abdel-Magid and C.A Maryanoff. Synthesis, 1990, 537;

M. Schlosser et al. Organometallics in Synthesis. A Manual, (M. Schlosser, Ed.),

Wiley &Sons Ltd: Chichester, UK, 2002, and references cited therein;

L. Wengwei et al., Tetrahedron Lett, 2006, 47, 1941 ;

M. Plotkin et al. Tetrahedron Lett, 2000, 41, 2269; Seyden-Penne, J. Reductions by the Alumino and Borohydrides, VCH, NY, 1991 ; O. C. Dermer, Chem. Rev., 1934, 14, 385;

N. Defacqz, et al., Tetrahedron Lett., 2003, 44, 9111 ;

S.J. Gregson et al., J. Med. Chem., 2004, 47, 1161 ;

A. M. Abdel Magib, et a/., J. Org. Chem., 1996, 61, 3849;

A.F. Abdel-Magid and C.A Maryanoff. Synthesis, 1990, 537;

T. Ikemoto and M. Wakimasu, Heterocycles, 2001 , 55, 99;

E. Abignente et al., II Farmaco, 1990, 45, 1075;

T. Ikemoto et al., Tetrahedron, 2000, 56, 7915;

T. W. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis, Wiley, NY, 1999;

S. Y. Han and Y.-A. Kim. Tetrahedron, 2004, 60, 2447;

J. A. H. Lainton et a/., J. Comb. Chem., 2003, 5, 400; or

Wiggins, J. M. Synth. Commun., 1988, 18, 741.

Other specific transformation steps (including those that may be employed in order to form compounds of formula I) that may be mentioned include:

(i) reductions, for example of a carboxylic acid (or ester) to either an aldehyde or an alcohol, using appropriate reducing conditions (e.g. -C(0)OH (or an ester thereof), may be converted to a -C(0)H or -CH₂-OH group, using DIBAL and LiAIH₄, respectively (or similar chemoselective reducing agents));

(ii) reductions of an aldehyde (-C(O)H) group to an alcohol group (-CH₂OH), using appropriate reduction conditions such as those mentioned at point (i) above;

(iii) oxidations, for example of a moiety containing an alcohol group (e.g. -CH₂OH) to an aldehyde (e.g. -C(O)H) or of a -S- moiety to a -S(O)- or -S(0)₂- moiety (or the reverse reduction reaction), for example in the presence of a suitable oxidising agent, e.g. Mn0₂ or mcpba or the like;

(iv) reductive amination of an aldehyde and an amine, under appropriate reaction conditions, for example in "one-pot" procedure in the presence of an appropriate reducing agent, such as a chemoselective reducing agent such as sodium cyanoborohydride or, preferably, sodium triacetoxyborohydride, or the like. Alternatively, such reactions may be performed in two steps, for example a condensation step (in the presence of e.g. a dehydrating agent such as trimethyl orthoformate or MgS0₄ or molecular sieves, etc) followed by a reduction step (e.g. by reaction in the presence of a reducing agent such as a chemoselective one mentioned above or NaBH₄, AIH₄, or the like), for instance the conversion of -NH₂ to -N(H)-isopropyl by condensation in the presence of acetone (H₃C-C(0)-CH₃) followed by reduction in the presence of a reducing agent such as sodium cyanaoborohydride (i.e. overall a reductive amination);

(v) formation of an amide or sulfonamide, for example by reaction of a sulfonyl choride with an amine or by an amide coupling reaction, i.e. the formation of an amide from a carboxylic acid (or ester thereof), for example -C(0)OH (or an ester thereof), may be converted to -C(O)N(R²⁰)R²¹ group (in which R²⁰ and R² are as hereinbefore defined, and may be linked together, e.g. as defined above), and which reaction may (e.g. for -COOH) be performed in the presence of a suitable coupling reagent (e.g. 1 ,1'-carbonyldiimidazole, A/./V-dicyclohexylcarbodiimide, or the like) or, in the case of an ester (e.g. -C(0)OCH₃ or -C(0)OCH₂CH₃), be performed in the presence of e.g. trimethylaluminium, or, alternatively the -C(0)OH group may first be activated to the corresponding acyl halide (e.g -C(0)CI, by treatment with oxalyl chloride, thionyl chloride, phosphorous pentachloride, phosphorous oxychloride, or the like), and, in all cases, the relevant compound is reacted with a compound of formula HN(R^Z0)R²¹ (in which R²⁰ and R²¹ are as hereinbefore defined), under standard conditions known to those skilled in the art (e.g. optionally in the presence of a suitable solvent, suitable base and/or in an inert atmosphere);

(vi) conversion of a primary amide to a nitrile functional group, for example under dehydration reaction conditions, e.g. in the presence of POCI₃, or the like;

(vii) nucleophilic substitution (e.g. aromatic nucleophilic substitution) reactions, where any nucleophile replaces a leaving group, e.g. an amine may replace a -S(0)CH₃ leaving group;

(viii) transformation of a methoxy group to a hydroxy group, by reaction in the presence of an appropriate reagent, such as boron fluoride-dimethyl sulfide complex or BBr₃ (e.g. in the presence of a suitable solvent such as dichloromethane);

(ix) alkylation, acylation or sulfonylation reactions, which may be performed in the presence of base and solvent (such as those described hereinbefore);

(x) specific deprotection steps, such as deprotection of an A/-Boc protecting group by reaction in the presence of an acid, or, a hydroxy group protected as a silyl ether (e.g. a tert-butyl-dimethylsilyl protecting group) may be deprotected by reaction with a source of fluoride ions, e.g. by employing the reagent tetrabutylammonium fluoride (TBAF);

(xi) aromatic nitration reactions (for instance which may be performed on compounds corresponding to compounds of formula X, but in which the -NH₂ group is replaced with a -N0₂ group; subsequent conversion of the nitro group may take place separately - see (xii) below); e.g. by reaction in the presence of nitric acid at low temperature, followed by addition of cone. H₂S0₄);

(xii) reductions of nitro groups to amino groups under standard conditions, e.g. iron-based reduction), which may be followed by an acylation reaction (see (ix) above) or a reductive amination (see (iv) above).

The substituents R¹, R², R³, R⁴, Y and Z (or substituents on the main core structure, including substituents on ring A or on linker groups Y and Z) in final compounds of the invention or relevant intermediates may be modified one or more times, after or during the processes described above by way of methods that are well known to those skilled in the art. Examples of such methods include substitutions, reductions, oxidations, alkylations, acylations, hydrolyses, esterifications, etherifications, halogenations or nitrations. Such reactions may result in the formation of a symmetric or asymmetric final compound of the invention or intermediate. The precursor groups can be changed to a different such group, or to the groups defined in formula I, at any time during the reaction sequence. For example, in cases in which there is a -C0₂H present, the skilled person will appreciate that at any stage during the synthesis (e.g. the final step), the relevant ester group may be hydrolysed to form a carboxylic acid functional group.

For example, when substituents in the compounds of the invention such as C0₂Et, CHO, CN and/or CH₂CI, are present, these groups can be further derivatized to other fragments described (e.g. by those integers mentioned above) in compounds of the invention, following synthetic protocols very well know to the person skilled in the art and/or according to the experimental part described in the patent. Other specific transformation steps that may be mentioned include: the reduction of a nitro or azido group to an amino group; the hydrolysis of a nitrile group to a carboxylic acid group; and standard nucleophilic aromatic substitution reactions, for example in which an iodo-, preferably, fluoro- or bromo-phenyl group is converted into a cyanophenyl group by employing a source of cyanide ions (e.g. by reaction with a compound which is a source of cyano anions, e.g. sodium, copper (I), zinc or potassium cyanide, optionally in the presence of a palladium catalyst) as a reagent (alternatively, in this case, palladium catalysed cyanation reaction conditions may also be employed).

Other transformations that may be mentioned include: the conversion of a halo group (preferably iodo or bromo) to a -alkynyl group (e.g. by reaction with a 1- alkyne), which latter reaction may be performed in the presence of a suitable coupling catalyst (e.g. a palladium and/or a copper based catalyst) and a suitable base (e.g. a tri-(C_1-6 alkyl)amine such as triethylamine, tributylamine or ethyldiisopropylamine); the introduction of amino groups and hydroxy groups in accordance with standard conditions using reagents known to those skilled in the art; the conversion of an amino group to a halo, azido or a cyano group, for example via diazotisation (e.g. generated in situ by reaction with NaN0₂ and a strong acid, such as HCI or H₂S0₄, at low temperature such as at 0°C or below, e.g. at about -5°C) followed by reaction with the appropriate nucleophile e.g. a source of the relevant anions, for example by reaction in the presence of a halogen gas (e.g. bromine, iodine or chlorine), or a reagent that is a source of azido or cyanide anions, such as NaN₃ or NaCN; the conversion of -C(0)OH to a -NH₂ group, under Schmidt reaction conditions, or variants thereof, for example in the presence of HN₃ (which may be formed in by contacting NaN₃ with a strong acid such as H₂S0₄), or, for variants, by reaction with diphenyl phosphoryl azide ((PhO)₂P(0)N₃) in the presence of an alcohol, such as ferf-butanol, which may result in the formation of a carbamate intermediate; the conversion of -C(0)NH₂ to -NH₂, for example under Hofmann rearrangement reaction conditions, for example in the presence of NaOBr (which may be formed by contacting NaOH and Br₂) which may result in the formation of a carbamate intermediate; the conversion of -C(0)N₃ (which compound itself may be prepared from the corresponding acyl hydrazide under standard diazotisation reaction conditions, e.g. in the presence of NaN0₂ and a strong acid such as H₂S0₄ or HCI) to -NH₂, for example under Curtius rearrangement reaction conditions, which may result in the formation of an intermediate isocyanate (or a carbamate if treated with an alcohol); the conversion of an alkyl carbamate to -NH₂, by hydrolysis, for example in the presence of water and base or under acidic conditions, or, when a benzyl carbamate intermediate is formed, under hydrogenation reaction conditions (e.g. catalytic hydrogenation reaction conditions in the presence of a precious metal catalyst such as Pd); halogenation of an aromatic ring, for example by an electrophilic aromatic substitution reaction in the presence of halogen atoms (e.g. chlorine, bromine, etc, or an equivalent source thereof) and, if necessary an appropriate catalyst/Lewis acid (e.g. AICI₃ or FeCIa).

Compounds of the invention bearing a carboxyester functional group may be converted into a variety of derivatives according to methods well known in the art to convert carboxyester groups into carboxamides, N-substituted carboxamides, Ν,Ν-disubstituted carboxamides, carboxylic acids, and the like. The operative conditions are those widely known in the art and may comprise, for instance in the conversion of a carboxyester group into a carboxamide group, the reaction with ammonia or ammonium hydroxide in the presence of a suitable solvent such as a lower alcohol, dimethylformamide or a mixture thereof; preferably the reaction is carried out with ammonium hydroxide in a methanol/dimethyl- formamide mixture, at a temperature ranging from about 50°C to about 100°C. Analogous operative conditions apply in the preparation of N-substituted or N,N- disubstituted carboxamides wherein a suitable primary or secondary amine is used in place of ammonia or ammonium hydroxide. Likewise, carboxyester groups may be converted into carboxylic acid derivatives through basic or acidic hydrolysis conditions, widely known in the art. Further, amino derivatives of compounds of the invention may easily be converted into the corresponding carbamate, carboxamido or ureido derivatives.

Compounds of the invention may be isolated from their reaction mixtures using conventional techniques (e.g. recrystallisations). It will be appreciated by those skilled in the art that, in the processes described above and hereinafter, the functional groups of intermediate compounds may need to be protected by protecting groups.

The need for such protection will vary depending on the nature of the remote functionality and the conditions of the preparation methods (and the need can be readily determined by one skilled in the art). Suitable amino-protecting groups include acetyl, trifluoroacetyl, t-butoxycarbonyl (BOC), benzyloxycarbonyl (CBz), 9-fluorenylmethyleneoxycarbonyl (Fmoc) and 2,4,4-trimethylpentan-2-yl (which may be deprotected by reaction in the presence of an acid, e.g. HCI in water/alcohol (e.g. MeOH)) or the like. The need for such protection is readily determined by one skilled in the art.

The protection and deprotection of functional groups may take place before or after a reaction in the above-mentioned schemes.

Protecting groups may be removed in accordance with techniques that are well known to those skilled in the art and as described hereinafter. For example, protected compounds/intermediates described herein may be converted chemically to unprotected compounds using standard deprotection techniques.

The type of chemistry involved will dictate the need, and type, of protecting groups as well as the sequence for accomplishing the synthesis.

The use of protecting groups is fully described in "Protective Groups in Organic Synthesis", 3^rd edition, T.W. Greene & P.G.M. Wutz, Wiley-lnterscience (1999).

Medical and Pharmaceutical Uses

Compounds of the invention are indicated as pharmaceuticals. According to a further aspect of the invention there is provided a compound of the invention, as hereinbefore defined, for use as a pharmaceutical.

Compounds of the invention may inhibit protein kinases, such as CDK8, for example as may be shown in the tests described below and/or in tests known to the skilled person. As CDK8 kinase activity may be implicated in the regulation of nuclear β-catenin activity, the compounds of the invention may therefore be useful in the treatment of disorders in an individual in which the inhibition of CDK8 is desired/required (which includes disorders in which the regulation, or reduction of, nuclear β-catenin activity and/or inhibition, or modulation of, the expression of CDK8 (i.e. the oncogene) is desired/required). The term "inhibit" may refer to any measurable reduction and/or prevention of catalytic kinase (e.g. CDK8) activity. The reduction and/or prevention of kinase activity may be measured by comparing the kinase activity in a sample containing a compound of the invention and an equivalent sample of kinase (e.g. CDK8) in the absence of a compound of the invention, as would be apparent to those skilled in the art. The measurable change may be objective (e.g. measurable by some test or marker, for example in an in vitro or in vivo assay or test, such as one described hereinafter, or otherwise another suitable assay or test known to those skilled in the art) or subjective (e.g. the subject gives an indication of or feels an effect).

Compounds of the invention may be found to exhibit 50% inhibition of a protein kinase activity (e.g. CDK8) at a concentration of 100 μΜ or below (for example at a concentration of below 50 μΜ, or even below 10 μΜ, such as below 1 μΜ), when tested in an assay (or other test), for example as described hereinafter, or otherwise another suitable assay or test known to the skilled person.

Compounds of the invention are thus expected to be useful in the treatment of a disorder in which a protein kinase (e.g. CDK8) is known to play a role and which is characterised by or associated with an overall elevated activity of that kinase (due to, for example, increased amount of the kinase or increased catalytic activity of the kinase). The compounds of the invention may also be useful in the treatment of conditions/disorders associated with elevated nuclear β-catenin activity and/or elevated expression (or over-expression) of CDK8 (i.e. the known oncogene).

Hence, compounds of the invention are expected to be useful in the treatment of a disease/disorder arising from abnormal cell growth, function or behaviour associated with the protein kinase (e.g. CDK8). Such conditions/disorders include cancer, immune disorders, cardiovascular diseases, viral infections, inflammation, metabolism/endocrine function disorders, neurological disorders and autoimmune disorders. In particular such conditions/disorders include cancers, especially specific cancers such as colon/colorectal cancer(s) and it is therefore particularly preferred that compounds of the invention may be of use in treating such specific cancers.

The disorders/conditions that the compounds of the invention may be useful in treating hence includes cancer (such as lymphomas, solid tumours or a cancer as described hereinafter), obstructive airways diseases, allergic diseases, inflammatory diseases (such as asthma, allergy and Chrohn's disease), immunosuppression (such as transplantation rejection and autoimmune diseases), disorders commonly connected with organ transplantation, AIDS- related diseases and other associated diseases. Other associated diseases that may be mentioned (particularly due to the key role of kinases in the regulation of cellular proliferation) include other cell proliferative disorders and/or non- malignant diseases, such as benign prostate hyperplasia, familial adenomatosis, polyposis, neurofibromatosis, psoriasis, bone disorders, atherosclerosis, vascular smooth cell proliferation associated with atherosclerosis, pulmonary fibrosis, arthritis glomerulonephritis and post-surgical stenosis and restenosis. Other disease states that may be mentioned include cardiovascular disease, stroke, diabetes, hepatomegaly, Alzheimer's disease, cystic fibrosis, hormone- related diseases, immunodeficiency disorders, destructive bone disorders, infectious diseases, conditions associated with cell death, thrombin-induced platelet aggregation, chronic myelogenous leukaemia, liver disease, pathologic immune conditions involving T cell activation and CNS disorders.

As stated above, the compounds of the invention may be useful in the treatment of cancer. More, specifically, the compounds of the invention may therefore be useful in the treatment of a variety of cancer including, but not limited to: carcinoma such as cancer of the bladder, breast, colon, kidney, liver, lung (including non-small cell cancer and small cell lung cancer), esophagus, gallbladder, ovary, pancreas, stomach, cervix, thyroid, prostate, skin, squamous cell carcinoma, testis, genitourinary tract, larynx, glioblastoma, neuroblastoma, keratoacanthoma, epidermoid carcinoma, large cell carcinoma, non-small cell lung carcinoma, small cell lung carcinoma, lung adenocarcinoma, bone, adenoma, adenocarcinoma, follicular carcinoma, undifferentiated carcinoma, papilliary carcinoma, seminona, melanoma, sarcoma, bladder carcinoma, liver carcinoma and biliary passages, kidney carcinoma, myeloid disorders, lymphoid disorders, hairy cells, buccal cavity and pharynx (oral), lip, tongue, mouth, pharynx, small intestine, colon-rectum, large intestine, rectum, brain and central nervous system, Hodgkin's and leukaemia; hematopoietic tumors of lymphoid lineage, including leukemia, acute lymphocitic leukemia, acute lymphoblastic leukemia, B-cell lymphoma, T-cell-lymphoma, Hodgkin's lymphoma, non- Hodgkin's lymphoma, hairy cell lymphoma and Burkett's lymphoma; hematopoietic tumors of myeloid lineage, including acute and chronic myelogenous leukemias, myelodysplastic syndrome and promyelocytic leukemia; tumors of mesenchymal origin, including fibrosarcoma and rhabdomyosarcoma; tumors of the central and peripheral nervous system, including astrocytoma, neuroblastoma, glioma and schwannomas; and other tumors, including melanoma, seminoma, teratocarcinoma, osteosarcoma, xeroderma pigmentosum, keratoxanthoma, thyroid follicular cancer and Kaposi's sarcoma. Compounds of the invention are indicated both in the therapeutic and/or prophylactic treatment of the above-mentioned conditions.

According to a further aspect of the present invention, there is provided a method of treatment of a disease (e.g. cancer or another disease as mentioned herein, especially colon/colorectal cancer) which is associated with the inhibition of a protein kinase (e.g. CDK8) i.e. where such inhibition is desired and/or required (the disease may also be associated with increased nuclear β-catenin activity and/or elevated expression of CDK8), for example, a method of treatment of a disease/disorder arising from abnormal cell growth, function or behaviour associated with protein kinases, e.g. CDK8, which method comprises administration of a therapeutically effective amount of a compound of the invention, as hereinbefore defined, to a patient suffering from, or susceptible to, such a condition. "Patients" include mammalian (including human) patients. Hence, the method of treatment discussed above may include the treatment of a human or animal body.

The term "effective amount" refers to an amount of a compound, which confers a therapeutic effect on the treated patient. The effect may be objective (e.g. measurable by some test or marker) or subjective (e.g. the subject gives an indication of or feels an effect).

Compounds of the invention may be administered orally, intravenously, subcutaneously, buccally, rectally, dermally, nasally, tracheally, bronchially, sublingually, by any other parenteral route or via inhalation, in a pharmaceutically acceptable dosage form.

Compounds of the invention may be administered alone, but are preferably administered by way of known pharmaceutical formulations, including tablets, capsules or elixirs for oral administration, suppositories for rectal administration, sterile solutions or suspensions for parenteral or intramuscular administration, and the like. The type of pharmaceutical formulation may be selected with due regard to the intended route of administration and standard pharmaceutical practice. Such pharmaceutically acceptable carriers may be chemically inert to the active compounds and may have no detrimental side effects or toxicity under the conditions of use.

Such formulations may be prepared in accordance with standard and/or accepted pharmaceutical practice. Otherwise, the preparation of suitable formulations may be achieved non-inventively by the skilled person using routine techniques and/or in accordance with standard and/or accepted pharmaceutical practice.

According to a further aspect of the invention there is thus provided a pharmaceutical formulation including a compound of the invention, as hereinbefore defined, in admixture with a pharmaceutically acceptable adjuvant, diluent and/or carrier.

Depending on e.g. potency and physical characteristics of the compound of the invention (i.e. active ingredient), pharmaceutical formulations that may be mentioned include those in which the active ingredient is present in at least 1 % (or at least 10%, at least 30% or at least 50%) by weight. That is, the ratio of active ingredient to the other components (i.e. the addition of adjuvant, diluent and carrier) of the pharmaceutical composition is at least 1 :99 (or at least 10:90, at least 30:70 or at least 50:50) by weight. The amount of compound of the invention in the formulation will depend on the severity of the condition, and on the patient, to be treated, as well as the compound(s) which is/are employed, but may be determined non-inventively by the skilled person.

The invention further provides a process for the preparation of a pharmaceutical formulation, as hereinbefore defined, which process comprises bringing into association a compound of the invention, as hereinbefore defined, or a pharmaceutically acceptable ester, amide, solvate or salt thereof with a pharmaceutically-acceptable adjuvant, diluent or carrier.

Compounds of the invention may also be combined with other therapeutic agents that are inhibitors of kinases (e.g. protein por lipid kinases, such as CDK8) and/or useful in the treatment of a cancer and/or a proliferative disease. Compounds of the invention may also be combined with other therapies (e.g. radiation).

According to a further aspect of the invention, there is provided a combination product comprising:

(A) a compound of the invention, as hereinbefore defined; and

(B) another therapeutic agent that is useful in the treatment of cancer and/or a proliferative disease,

wherein each of components (A) and (B) is formulated in admixture with a pharmaceutically-acceptable adjuvant, diluent or carrier.

Such combination products provide for the administration of a compound of the invention in conjunction with the other therapeutic agent, and may thus be presented either as separate formulations, wherein at least one of those formulations comprises a compound of the invention, and at least one comprises the other therapeutic agent, or may be presented (i.e. formulated) as a combined preparation (i.e. presented as a single formulation including a compound of the invention and the other therapeutic agent).

Thus, there is further provided: (1) a pharmaceutical formulation including a compound of the invention, as hereinbefore defined, another therapeutic agent that is useful in the treatment of cancer and/or a proliferative disease, and a pharmaceutically-acceptable adjuvant, diluent or carrier; and

(2) a kit of parts comprising components:

(a) a pharmaceutical formulation including a compound of the invention, as hereinbefore defined, in admixture with a pharmaceutically-acceptable adjuvant, diluent or carrier; and

(b) a pharmaceutical formulation including another therapeutic agent that is useful in the treatment of cancer and/or a proliferative disease in admixture with a pharmaceutically-acceptable adjuvant, diluent or carrier, which components (a) and (b) are each provided in a form that is suitable for administration in conjunction with the other.

The invention further provides a process for the preparation of a combination product as hereinbefore defined, which process comprises bringing into association a compound of the invention, as hereinbefore defined, or a pharmaceutically acceptable ester, amide, solvate or salt thereof with the other therapeutic agent that is useful in the treatment of cancer and/or a proliferative disease, and at least one pharmaceutically-acceptable adjuvant, diluent or carrier.

By "bringing into association", we mean that the two components are rendered suitable for administration in conjunction with each other.

Thus, in relation to the process for the preparation of a kit of parts as hereinbefore defined, by bringing the two components "into association with" each other, we include that the two components of the kit of parts may be:

(i) provided as separate formulations (i.e. independently of one another), which are subsequently brought together for use in conjunction with each other in combination therapy; or

(ii) packaged and presented together as separate components of a "combination pack" for use in conjunction with each other in combination therapy. Depending on the disorder, and the patient, to be treated, as well as the route of administration, compounds of the invention may be administered at varying therapeutically effective doses to a patient in need thereof. However, the dose administered to a mammal, particularly a human, in the context of the present invention should be sufficient to effect a therapeutic response in the mammal over a reasonable timeframe. One skilled in the art will recognize that the selection of the exact dose and composition and the most appropriate delivery regimen will also be influenced by inter alia the pharmacological properties of the formulation, the nature and severity of the condition being treated, and the physical condition and mental acuity of the recipient, as well as the potency of the specific compound, the age, condition, body weight, sex and response of the patient to be treated, and the stage/severity of the disease.

Administration may be continuous or intermittent (e.g. by bolus injection). The dosage may also be determined by the timing and frequency of administration. In the case of oral or parenteral administration the dosage can vary from about 0.01 mg to about 1000 mg per day of a compound of the invention.

In any event, the medical practitioner, or other skilled person, will be able to determine routinely the actual dosage, which will be most suitable for an individual patient. The above-mentioned dosages are exemplary of the average case; there can, of course, be individual instances where higher or lower dosage ranges are merited, and such are within the scope of this invention. Compounds of the invention may have the advantage that they are effective inhibitors of protein kinases (e.g. CDK8). Advantegously, compounds of the invention may inhibit (e.g. selectively) certain protein kinases (e.g. CDK8), without exhibiting inhibition (or significant inhibition) of other protein or lipid kinases. For instance, the compounds of the invention may selectively inhibit only one protein kinase (e.g. CDK8).

Compounds of the invention may also have the advantage that they may be more efficacious than, be less toxic than, be longer acting than, be more potent than, produce fewer side effects than, be more easily absorbed than, and/or have a better pharmacokinetic profile (e.g. higher oral bioavailability and/or lower clearance) than, and/or have other useful pharmacological, physical, or chemical properties over, compounds known in the prior art, whether for use in the above- stated indications or otherwise. Compounds of the invention may be beneficial as they are medicaments with targeted therapy, i.e. which target a particular molecular entity by interfering with or inhibiting it (e.g. in this case by inhibiting a protein kinase as hereinbefore described). Compounds of the invention may therefore also have the benefit that they have a new effect (for instance as compared to known compounds in the prior art), for instance, the new effect may be a particular mode of action or another effect resultant of the targeted therapy. Targeted therapies may be beneficial as they may have the desired effect (e.g. reduce cancer, such as colon/colorectal cancer, by reducing tumor growth or carcinogenisis) but may also have the advantage of reducing side effects (e.g. by preventing the killing of normal cells, as may occur using e.g. chemotherapy).

Furthermore, compounds of the invention may selectively target a particular protein kinase (e.g. CDK8) compared to other known protein or lipid kinases. Accordingly, compounds of the invention may have the advantage that certain, specific, cancers (e.g. colon/colorectal cancer) may be treated selectively, which selective treatment may also have the effect of reducing side effects.

Targeted therapies (such as CDK8 targeted therapy) could potentially have other advantages over current anti-cancer treatments, for instance because it may not interact with DNA (compared to certain known anti-tumour therapies) and should therefore reduce the risk of secondary tumour development.

Examples/Biological Tests CDK8/Cvclin C binding assay

The biding assay relies on the LanthaScreen™ Eu-Kinase Binding Assay (Invitrogen. This is a kinase assay platform based on measuring the binding and displacement of an Alexa Fluor® 647 conjugate of an ATP-competitive kinase inhibitor (Kinase Tracer 236, PV5592) at a kinase active site. Binding of the tracer to the kinase is detected by addition of a europium (Eu)-labeled anti-His antibody (Invitrogen PV 5596), which specifically labels the kinase of interest. This binding results in a high degree of fluorescence resonance energy transfer (FRET), whereas displacement of the tracer with a kinase inhibitor results in a loss of FRET.

The enzyme has been purchase from Invitrogen (PV4402) as a dimer of full- length His-tagged recombinant human proteins. Assay conditions were as indicated by the kit manufacturers with the following adaptations:

• Assay buffer: 50 mM HEPES, pH 7.5, 1 mM EGTA, 0.01% Brij-35, 10 mM MgCI₂

· Assay volume: 25 μΙ

• Incubation time and temperature: 60 min at 25°C

• Cdk8-Cyclin C concentration: 5 nM

• Tracer concentration: 10 nM

• (Eu)-labeled anti-His antibody concentration: 1.5 nM

· Tested compound: Serial 1 :3 dilutions

• Final DMSO concentration in the assay: 0.4%

Assays were performed in 384-well plates. The final read out was generated using an EnVision plate reader (Perkin-Elmer). The emission ratio was calculated by dividing the acceptor/tracer emission (665 nm) by the antibody/donor emission (615 nm).

Reporter system to assay β-catenin transcriptional activity Efficacy of compounds of the invention on the inhibition of the transcriptional activity of β-catenine driven by CDK8 is measured in a Luminescent reporter assay. EC₅₀ values are established for the tested compounds.

The TOPFIash luciferase reporter system has been adopted as a standard for detecting β-catenin driven transcriptional activation. The reporter used is a 6X TOPFIash reporter meaning that it contains 6 TCF/LEF-1 binding sites upstream of a minimal promoter driving expression of Firefly luciferase. A FOPFIash reporter, which contains mutated TCF sites upstream of Renilla luciferase open frame in the enhancer region, is used as a negative control to show that the change in luciferase activity is specifically due to β-catenin transcriptional activity (Promega). The detection is done with the Dual-Glo® Luciferase Assay System (Promega); this is a homogeneous reagent system that enables fast and simple quantitation of a stable luminescent signal from two reporter genes in a single sample. This convenient "add-and-read" system generates both firefly and Renilla luciferase luminescence signals from cells that have not been preconditioned or prelysed. The assay was conducted in 96-well plates making it amenable to automated highthroughput screening (HTS).

Procedure

HTC116 colon cancer cells were seeded, 15000 cells per well, into 96-well plates and incubated for 16 h at 37°C, 5% C0₂. On day two, the cells were transfected using Effectene reactive (Quiagen) with TOPFIash and FOPFIash luciferase reporters plasmids. Cells were incubated with transfection complexes under normal growth conditions for 5h. Eight serial 1 :3 compound dilutions are made in DMSO in a 96-well plate. The compounds are added to duplicate wells in 96-well cell plates using a FX BECKMAN robot (Beckman Coulter) and are incubated at 37°C under C0₂ atmosphere over night. The third day, the inhibition of transcripitional activity of β-catenin was measured using Dual-Glo® Luciferase Assay System (Promega) and read on VICTOR (Perkin Elmer). EC₅₀ values are calculated using ActivityBase from IDBS.

Examples and Experimental Scheme 1:

Scheme 3:

Experimental part:

Herein after, the term "DCM" means dichloromethane, "MeOH" means methanol, "THF" means tetrahydrofuran, "DMF" means dimethylformamide, "DME" means 1 ,2-dimethoxyethane, "EtOAc" means ethyl acetate, "Pd(PPh₃)₄" means tetrakis(triphenylphosphine)palladium, "DIPEA" means diisopropylethylamine, "min" means minutes, "h" means hours, "eq" means equivalents, "nBuOH " means n-butanol, "mw" means microwave, "CCTLC" means centrifugal circular thin-layer chromatography.

General Procedure

NMR spectra were recorded in a Bruker Avance II 300 spectrometer and Bruker Avance II 700 spectrometer fitted with 5mm QXI 700 S4 inverse phase, Z- gradient unit and variable temperature controller. The HPLC measurements were performed using a HP 1100 from Agilent Technologies comprising a pump (binary) with degasser, an autosampler, a column oven, a diode-array detector (DAD) and a column as specified in the respective methods below. Flow from the column was split to a MS spectrometer. The MS detector was configured with an electrospray ionization source or API/APCI. Nitrogen was used as the nebulizer gas. Data acquisition was performed with ChemStation LC/MSD quad, software.

Method 1

Reversed phase HPLC was carried out on a Gemini-NX C18 (100 x 2.0 mm; 5um).

Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 5% to 100% of B within 8 min at 50 °C, DAD.

Method 2

Reversed phase HPLC was carried out on a Gemini-NX C18 (100 x 2.0 mm; 5um).

Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 5% to 40% of B within 8 min at 50 °C, DAD.

Method 3

Reversed phase HPLC was carried out on a Gemini-NX C18 (100 x 2.0 mm; 5um).

Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 0% to 30% of B within 8 min at 50 °C, DAD.

Method 4

Reversed phase HPLC was carried out on a Gemini C18 column (50 x 2 mm, 3 urn).

Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 10% to 95% of B within 4 min at 50°C, DAD.

Method 5

Reversed phase HPLC was carried out on a Gemini C18 column (50 x 2 mm, 3 urn). Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 0% to 30% of B within 4 min at 50°C, DAD.

"Found mass" refers to the most abundant isotope detected in the HPLC-MS. Preparation of intermediates. General procedure A-1

The corresponding 3-Bromo-6-chloro-imidazopyridazine (1.0 eq) was suspended in dioxane (0.5 mUmmol) and the appropriate n- boc diamine (2.7 eq) or amino alcohol (3 eq) was added. The mixture was heated under mw irradiation at 160°C for 2h. Water was added and the mixture was extracted with AcOEt. The organic phase was separated, dried (Na2S04), filtered and evaporated till dryness. The residue was purified by Biotage flash column chromatography (eluent: 4 to 6% MeOH in DCM) to give the desired product.

The intermediate compounds of Table 1 were prepared according to the general procedure A-1.

Table 1 -Imidazopyridazine Intermediates (1-01 to 1-15)

General procedure A-2

R„=C0₂H or OH The appropriate 3-Bromo-6-amino-imidazopyridazine (Intermediates 1-01 to 1-15) (1.0 eq) was dissolved in ,4-dioxane (1 mL/mmol) and Pd(PPh3)4 (0.1 eq), Cs2C03 (2 eq), the appropriate boronic acid (1.15 eq) and H20 (1 mlJmmol) were added. The mixture was heated under microwave irradiation at 140°C for 1 h. On cooling, the mixture was purified by column chromatography (Biotage, eluent: 5% to 30% MeOH in DCM) to give the expected product.

The intermediate compounds of Table 2 were prepared according to the general procedure A-2.

Table 2 -Imidazopyridazine Intermediates (2-01 to 2-23)

55



Yield

No. -R1 -R2 -R3 ~R4 -R5

%

2-21 * OH -H -H -H quant.

HO

2-22 \/ -H -H 75

Me

HO O e

2-23 -H -H -H quant.

HO

General procedure A-3

The appropriate 3-aryl-6-amino-imidazopyridazine (Intermediates 2-17 to 2-19) (1.0 eq) was dissolved in DMF (10 mL/mmol). Cs2C03 (4 eq) and the appropriate alkylating agent (ethyl bromoacetate or ethyl 4-bromobutyrate) (1.5 eq) were added. The mixture was heated at 60°C for 15 h. On cooling, the mixture was purified by column chromatography (Biotage, eluent: 5% to 10% MeOH in DCM) to give the expected product.

The intermediate compounds of Table 3 were prepared according to the general procedure A-3. Table 3 -Imidazopyridazine Intermediates (3-01 to 3-03)

General procedure A-4

The corresponding 3-aryl-6-amino-imidazopyridazine (Intermediates 2-20 to 2-22) was suspended in HBr 48% (10 mL/mmol) and the reaction mixture was refluxed for 1h. On cooling, the mixture was basified with NaHC03 (pH= 9-10) and extracted with CHCI3:iPrOH (1 :1). The organics were dried, filtered and evaporated. The residue was used in the next step without further purification. General procedure A-5

A mixture of the appropriate 3-aryl-6-amino-imidazopyridazine (Intermediate 2- 23) was dissolved in THF (10 mlJmmol) and PPh3 (1.2 eq), imidazole (3 eq) and iodine (1 eq) were added at RT. The mixture was stirred for 15 min and the same amounts of PPh3 (1.2 eq) and iodine (1 eq) were added. The reaction mixture was stirred for 1 h at RT. The mixture was adsorbed in silica and purified by column chromatography (Biotage, 25-S, 5% to 10% MeOH in DCM) to give the expected product.

The intermediate compounds of Table 4 were prepared according to the general procedures A-4 or A-5.

Table 4 -Imidazopyridazine Intermediates (4-01 to 4-04)

The final examples of compounds of the invention were prepared according to the general methods B-1 to B-9 described hereinafter.

Examples

General method B-1 :

A mixture of the appropriate 3-aryl-6-amino-imidazopyridazine (Intermediates 2- 01 to 2-16) (1.0 eq) was suspended in 1 ,4-dioxane (2.5 mLJmmol) and HCI 4M in 1 ,4-dioxane (10.0 eq) was added. The reaction mixture was stirred at RT for 2 h. The solvent was evaporated to give the deprotected product as the hydrochloric salt. The residue was suspended in DMF (25 mlJmmol) and DIPEA (10 eq) was added. This mixture was added using a syringe pump (2mLJh) to a solution of PyBOP (1.2 eq) and DMAP (1.2 eq) in DMF (75 mL/mmol). After the addition the mixture was stirred for 2 h and evaporated. The residue was purified by column chromatography (Biotage, 5% to 30% eOH in DCM) followed by semi- preparative HPLC (Gemini C18 (150 10 mm; 5 m), Solvent A: water with 0.1% formic acid; Solvent B: acetonitrile with 0.1% formic acid. Gradient: 40% of A to 0% of A). Some

compounds were isolated as their corresponding formic acid salts.

General method B-2:

The appropriate 3-aryl-6-amino-imidazopyridazine (Intermediates 4-01 to 4-04) (1.0 eq) was dissolved in DMF (75 mL/mmol) and Cs2C03 (2.5 eq) was added. The reaction mixture was heated at 70°C for 12h and then concentrated. The residue was purified by column chromatography (Biotage, 25-S, 4% to 15% MeOH in DCM), to give the expected product.

General method B-3:

The corresponding 3-aryl-6-amino-imidazopyridazine (Intermediates 3-01 to 3-03) (1.0 eq) was dissolved in MeOH (10 mL mmol) and UOH.H20 (3 eq) was added. The reaction mixture was stirred for 17 h at RT, then the mixture was evaporated. The residue was suspended in dioxane (4 mL/mmol) and HCI in dioxane (4 N, 4 mL/mmol) was carefully added. The mixture was stirred at RT for 30 min and then was evaporated. The residue was suspended in DMF (20 mL/mmol) and DIPEA (1 eq) was added. The mixture was added during using a syringe pump (2mL7h) to a solution of PyBOP (1.3 eq) and DMAP (1.3 eq) in DMF (100 mUmmol). After the addition, the mixture was stirred at RT for 18h and evaporated. The residue was purified by column chromatography (Biotage, 25-S, 5% to 25% MeOH in DCM) followed by prep-HPLC to give the expected product. Some compounds were isolated as their corresponding formic acid salts.

General method B-4:

To a stirred solution of the corresponding final compounds (9 or 15) (1.0 eq) in DCM (50 mL/mmol) at RT, boron fluoride-dimethyl sulfide complex (10 eq.) was added. The mixture was stirred at RT for 24h. NaHC03 (sat.) was added and the mixture was extracted with (DCM /MeOH: 90/10). The organic phase was separated, dried (NaS04) and evaporated till dryness. The residue was purified by CCTLC in a chromatotron, eluent: (DCM /MeOH (NH3): 92/8), to give the expected compound.

General method B-5:

The corresponding final compounds (1 , 5, 18, 19 or 21) (1.0 eq), were suspended in DMF (15 mUmmol) and NaH (1.2 eq) was added. The mixture was stirred at RT for 1h. Then, the appropriate alkylating agent (1.2 eq) was added. The reaction mixture was stirred at RT for 24 h. H₂0 was added and the mixture was extracted with AcOEt. The organic layer was dried (Na₂S0₄), filtered and evaporated. The residue was purified by prep-HPLC to give the expected products. Some compounds were isolated as their corresponding formic acid salts.

General method B-6:

The corresponding final compound (14) (1.0 eq), and the appropriate aldehyde (2 eq.), were mixed in methanol (10 mLJmmol) and then treated with sodium triacetoxyborohydride (3 eq.). The mixture was stirred at RT under N2 atmosphere for 24h. The reaction mixture was quenched by adding aqueous saturated NaHC03, and the mixture was extracted with AcOEt. The organic phase was separated, dried (Na2S04), filtered and evaporated till dryness. The residue was purified by prep-HPLC to give the expected compounds. Some compounds were isolated as their corresponding formic acid salts.

In some cases, the aldehyde contained an amine boc-protected, then, deprotection of the boc-protected obtained compounds was achieved by treatment with amberlyst(r) 15.

General method B-7:

The corresponding final compound (22) (1.0 eq) was dissolved in THF (10 m/mmol) and LiAIH4 (9 eq) was carefully added. The reaction mixture was stirred at reflux for 3 h. On cooling, H20 (0.5 mUmmol) was carefully added followed by NaOH 2N (0.5 mUmmol). The mixture was adsorbed in silica gel and purified by column chromatography (Biotage, 25-S, 10% to 100% MeOH in DCM) and by prep-HPLC to give the expected product. Some compounds were isolated as their corresponding formic acid salts. General method B-8:

To a solution of the corresponding final compound (7 or 24) (1.0 eq) in THF (20 mUmmol), borane-THF complex (10 eq) was added and the mixture was stirred at RT for 2h. The reaction was quenched with MeOH (10 mUmmol), then HCI/MeOH (1.25M) (10 mUmmol), was added and the mixture was heated at 70°C for 30min. The solvent was evaporated and the residue was taken up into DCM and washed with NaHC03. The organic phase was washed separated, dried (Na2S04), filtered and evaporated till dryness. The residue was purified by CCTLC on a chromatotron, to give the expected compounds.

General method B-9:

To a stirred solution of the corresponding final compound (11) (1.0 eq) in EtOH (50 mL/mmol), NaOH (4N) (15 mUmmol) was added. The mixture was stirred at RT for 18h. Additional amount of NaOH (4N) (15 mlJmmol) was added and the mixture was stirred at reflux for 18h. Water was added and the mixture was extracted first with DCM/MeOH, then with n-BuOH. The combined organic phases were dried (Na2S04), filtered and evaporated. The residue was purified by HPLC to give the expected compound.

The final compounds of Table 5 were prepared according to the general methods B-1 to B-9.

Table 5: Final products

66





Table 6: Analytical data and CDK8 activity - R_t means retention time (in minutes), [M+H]⁺ means the protonated mass of the compound, method refers to the method used for (LC)MS.

Compounds of the invention were found to inhibit CDK8, for example as tested in the binding assay described hereinbefore. Biological activity in CDK8 for certain examples is represented in Table 6 by semi-quantative results: IC50 >1μΜ (^*), IC50 <100 nM (^***), 100nM<IC50<1 μΜ (^**). There are also some quantitative data, in parentheses, which depict the actual IC50 values (nM) for representative examples. Table 6

CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in

Rt [M+1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 9.17 (s, 1 H), 8.16 (t, J = 5.3 Hz, H), 7.84 (m, 2H), 7.47 (m, 2H), 7.1 (t, J =

7 6.50 336.2 3 5.8 Hz, 1 H), 6.42 (d, J = 1.0 Hz, 1H), 3.16

(m, 2H), 3.06 (m, 2H), 2.36 (d, J = 0.7 Hz, 3H), 1.88 (m, 2H), 1.55 (m, 2H), 1.22 (m, 2H).

DMSO δ 8.88 (s, 1 H), 8.23 (t, J = 5.5 Hz,

8 4.94 336.2 3 1 H), 7.60 (m, 4H), 7.13 (t, J = 6.0 Hz, 1H),

6.59 (d, J = 9.6 Hz, 1H), 3.34 (m, 2H), 3.03 (m, 2H), 1.75 (m, 2H), 1.59 (m, 2H), 1.22 (m, 2H).

DMSO δ 9.02 (d, J = 2.1 Hz, 1 H), 8.19 (t, J

9 4.87 366.3 3 = 5.8 Hz, 1 H), 7.88 (m, 2H), 7.13 (t, J = 6.9

Hz, 2H), 6.43 (s, 1 H), 3.80 (s, 3H), 3.26 (m, 2H), 3.10 (m, 2H), 2.41 (s, 3H), 1.79 (m, 2H), 1.54 (m, 2H), 1.35 (m, 2H).

DMSO δ 9.34 (dd, J = 7.5, 2.2 Hz, 1 H), 8.29 (t, J = 5.5 Hz, 1 H), 7.84 (d, J = 4.8 Hz, 1 H), 7.62 (m, 1 H), 7.42 (dd, J = 11.5, 8.5

10 5.65 354.2 3 *

Hz, 1 H), 7.25 (t, J = 6.0 Hz, 1 H), 6.54 (d, J = 1.0 Hz, 1 H), 3.34 (m, 2H), 3. 1 (m, 2H), 2.45 (d, J = 1.0 Hz, 3H), 1.86 (m, 2H), 1.61 (m, 2H), 1.29 (m, 2H).

DMSO δ 10.17 (s, 1H), 8.87 (s, 1 H), 8.24 (t, J = 5.4 Hz, 1H), 8.15 (m, 1 H), 7.97 (m,

11 5.17 393.4 3 *

1 H), 7.78 (m, 1 H), 7.41 (m, 1 H), 6.63 (m, 1 H), 3.33 (m, 2H), 3.11 (m, 2H), 2.46 (s, 3H), 2.08 (s, 3H), 1.86 (m, 2H), 1.61 (m, 2H), 1.30 (m, 2H).

DMSO δ 9.12 (s, 1 H), 8.35 (t, J = 5.3 Hz,

12 5.88 354.2 3 * 1H), 8.06 (s, 1 H), 7.83 (dm, 1 H), 7.24 (m,

2H), 6.51 (d, J = 1.0 Hz, 1 H), 3.33 (m, 2H), 3.12 (m, 2H), 2.43 (d, J = 1.0 Hz, 3H), 1.88 (m, 2H), 1.62 (m, 2H), 1.32 (m, 2H).

DMSO δ 9.21 (t, J = 1.4 Hz, 1H), 8.37 (t, J = 5.4 Hz, 1 H), 8.09 (s, 1H), 8.03 (m, 1 H),

13 6.69 370.2 3 * 7.48 (m, 1 H), 7.24 (t, J = 5.8 Hz, 1 H), 6.51

(d, J = 1.0 Hz, 1 H), 3.32 (m, 2H), 3.11 (m, 2H), 2.43 (d, J = 1.0 Hz, 3H), 1.87 (m, 2H), 1.62 (m, 2H), 1.32 (m, 2H). CDK-8

Cpd. H NMR (300 MHz; δ in ppm, J in

t [M+1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 9.29 (s, 1H), 8.22 (m, 1H), 8.05

14 0.42 323.1 2 ** (s, 1H), 7.98 (d, J = 7.9 Hz, 1H), 7.79 (d, J

= 9.8 Hz, 1H), 7.55 (m, 2H), 7.44 (t, J = 5.7 Hz, 1H), 6.69 (d, J = 9.8 Hz, 1H), 3.28 (m, 6H), 2.98 (m, 2H).

DMSO δ 8.92 (s, 1H), 8.11 (m, 1H), 7.91 (s, 1H), 7.85 (d, J = 7.9 Hz, 1H), 7.68 (d, J

15 0.61 353.3 3 **

= 9.4 Hz, 1H), 7.28 (m, 1H), 7.08 (d, J = 8.7 Hz, 1H), 6.57 (d, J = 9.4 Hz, 1H), 3.75 (s, 3H), 3.26 (m, 4H), 3.06 (m, 2H), 2.81 (m, 2H).

DMSO δ 9.32 (s, 1H), 8.22 (t, J = 4.6 Hz, 1H), 8.06 (s, 1H), 7.97 (m, 1H), 7.79 (d, J =

16 3.03 324.1 1 **

9.7 Hz, 1H), 7.53 (m, 2H), 7.29 (t, J = 5.9 Hz, 1H), 6.69 (d, J = 9.7 Hz, 1H), 3.81 (m, 2H), 3.64 (m, 2H), 3.49 (m, 2H), 3.39 (m, 2H).

DMSO δ 8.36 (s, 1H), 8.12 (s, 1H), 7.89 (t, J = 5.2 Hz, 1H), 7.64 (s, 1H), 7.04 (t, J =

17 4.35 351.3 3 *

5.7 Hz, 1H), 6.99 (s, 1H), 6.76 (s, 1H), 6.38 (s, 1H), 5.21 (broad s, 2H), 3.21 (m, 2H), 3.03 (m, 2H), 2.35 (s, 3H), 1.80 (m, 2H), 1.52 (m,2H), 1.22 (m, 2H).

CDCI₃ δ 8.28 (m, 1H), 7.74 (s, 1H), 7.58 (d,

*** J = 9.6 Hz, 1H), 7.22 (d, J = 7.9 Hz, 1H),

18 3.44 295.1 1 7.18 (m, 1H), 6.76 (m, 1H), 6.31 (d, J = 9.6

(31) Hz, 1H), 4.56 (t, J = 5.8 Hz, 1H), 4.13 (m, 2H), 3.34 (m, 2H), 1.92 (m, 2H), 1.80 (m, 2H), 1.34 (m,2H).

*** DMSO δ δ 8.29 (m, 1H), 8.24 (s, 1H), 7.88

19 3.70 309.1 1 (d, J = 9.7 Hz, H), 7.69 (t, J = 5.9 Hz, 1H),

(49) 7.40 (m, 2H), 6.92 (m, 2H), 4.18 (m, 2H), 3.28 (m, 2H), 1.78 (m, 4H), 1.48 (m, 4H).

DMSO δ 9.15 ( broad s, 1H), 8.34 (d, J = 1.8 Hz, 1H), 8.16 (s, 1H), 7.73 (s, 1H), 7.29 (dd, J = 8.4, 1.9 Hz, 1H), 7.06 (t, J = 5.9

20 3.05 339.2 1 **

Hz, 1H), 6.86 (d, J = 8.4 Hz, 1H), 6.40 (s, 1H), 4.10 (t, J = 6.9 Hz, 2H), 3.28 (m, 2H), 2.40 (s, 3H), 1.75 (m, 4H), 1.58 (m, 2H), 1.47 (m, 2H). CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in

Rt [M+1]⁺ Meth. IC50

Nr. Hz)

*** DMSO δ 8.61 (d, J = 1.8 Hz, 1H), 7.85 (s,

21 2.72 297.1 1 1H), 7.78 (d, J = 9.7 Hz, 1H), 7.30 (m, 3H),

(25) 6.80 (m, 1H), 6.69 (d, J = 9.7 Hz, 1H), 4.33 (t, J = 6.6 Hz, 2H), 3.81 (m, 4H), 3.43 (m, 2H).

DMSO δ 8.37 (t, J = 6.2 Hz, 1H), 8.15 (s, 1H), 8.11 (m, 1H), 7.87 (s, 1H), 7.71 (d, J =

22 0.58 324.2 1 **

9.6 Hz, 1H), 7.43 (m, 1H), 7.35 (m, 1H), 7.23 (t, J = 6.2 Hz, 1H), 6.95 (m, 1H), 6.62 (d, J = 9.7 Hz, 1H), 4.52 (s, 2H), 3.34 (m, 2H), 3.19 (m,2H), 1.68 (m, 2H).

DMSO δ 7.91 (m, 1H), 7.72 (s, 1H), 7.71 (d, J = 9.9 Hz, 1H), 7.41 (m, 1H), 7.27 (m, 1H), 7.13 (t, J = 5.9 Hz, 1H), 7.07 (m, 1H),

23 2.77 378.1 1 ** 6.62 (d, J = 9.7 Hz, 1H), 5.11 (d, J = 12.1

Hz, 1H), 4.42 (d, J = 12.1 Hz, 1H), 4.21 (d, J = 12.3 Hz, 1H), 3.81 (d, J = 14.0 Hz, 1H), 3.40 (m, 1H), 3.23 (m, 1H), 3.04 (m, 1H), 2.59 (m, 1H), 1.97 (m, 1H), 1.81 (m, 2H), 1.57 (m, 2H), 1.39 (m, 1 H), 1.06 (m, 1 H).

DMSO δ 8.03 (s, 1H), 7.76 (s, 1H), 7.71 (d, J = 9.7 Hz, 1H), 7.34 (m, 1H), 7.26 (m, 1H), 7.13 (t, J = 6.5 Hz, 1H), 6.89 (dd, J = 8.0,

24 3.94 392.2 2 **

1.7 Hz, 1H), 6.66 (d, J = 9.7 Hz, 1H), 4.37 (d, J = 12.7 Hz, 1H), 4.01 (m, 3H), 3.25 (m, 2H), 3.08 (m, 1H), 2.81 (m, 1H), 2.52 (m, 1H), 2.10 (m, 3H), 1.85 (m, 2H), 1.55 (m, 2H), 1.25 (m, 1H).

DMSO δ 11.56 (s, 1H), 9.04 (s, 1H), 8.53 (m, 1H), 7.77 (m, 2H), 7.12 (t, J = 5.5 Hz,

25 6.19 352.1 3 **

1H), 6.96 (d, J = 8.6 Hz, 1H), 6.44 (s, 1H), 3.17 (m, 2H), 3.09 (m, 2H), 2.42 (s, 3H), 1.88 (m, 2H), 1.66 (m, 2H), 1.31 (m, 2H).

DMSO δ 11.66 (s, 1H), 9.11 (d, J = 2.1 Hz, 1H), 8.26 (m, 1H), 7.86 (s, 1H), 7.82 (dd, J

26 0.35 339.0 3 ** = 8.6, 2.1 Hz, 1H), 7.73 (d, J =9.6 Hz, 1H),

7.23 (t, J =6.1 Hz, 1H), 6.97 (d, J = 8.6 Hz, 1H), 6.61 (d, J = 9.6 Hz, 1H), 3.26 (m, 4H), 3.01 (m, 2H), 2.83 (m, 2H). CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in

t [M+1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 9.17 (s, 1 H), 8.28 (t, J = 5.7 Hz, 1 H), 8.09 (s, 1H), 7.95 (m, 1H), 7.86 (d, J = 10.0 Hz, 1H), 7.55 (m, 2H), 7.28 (m, 2H),

27 5.98 430.2 1 _** 7.17 (t, J = 8.9 Hz, 3H), 6.92 (d, J = 10.0

Hz, 1H), 6.58 (s, 1 H), 4.78 (s, 2H), 3.43 (m, 4H), 1.93 (m, 2H), 1.63 (m, 2H), 1.26 (m, 2H).

CDCI3 δ 9.19 (s, 1 H), 8.00 (s, 1 H), 7.87 (m, 2H), 7.72 (m, 1 H), 7.55 (m, 1 H), 7.43

28 5.92 480.1 1 _* (d, J = 8.0 Hz, 1 H), 7.31 (s, 1 H), 7.06 (m,

1H), 6.53 (d, J = 9.7 Hz, 1 H), 6.11 (m, 1H), 4.63 (s, 2H), 3.59 (m, 4H), 2.01 (m, 2H), 1.76 (m, 2H), 1.54 (m, 2H).

CDCI3 δ 9.16 (s, 1 H), 8.12 (s, 1 H), 7.94 (s, 1 H), 7.82 (m, 3H), 7.55 (m, 1H), 6.85 (d, J

29 4.46 376.2 1 = 10.1 Hz, 1H), 6.08 (m, 1H), 3.57 (m, 4H),

3.35 (d, J = 6.1 Hz, 2H), 1.88 (m, 2H), 1.77 (m, 2H), 1.52 (m, 2H), 1.03 (m, 1 H), 0.62 (m, 2H), 0.30 (m, 2H).

DMSO δ 8.80 (s, 1 H), 8.39 (t, J = 5.5 Hz, 1H), 7.92 (s, 1 H), 7.85 (m, 2H), 7.57 (m, 4H), 7.12 (d, J = 10.1 Hz, 1 H), 3.48 (m,

30 4.72 390.2 1 _** 2H), 3.41 (m, 2H), 3.32 (m, 2H), 1.76 (m,

2H), 1.59 (m, 2H), 1.51 (m, 2H), 1.36 (m, 2H), 1.01 (m, 1 H), 0.48 (m, 2H), 0.31 (m, 2H).

DMSO δ 8.33 (m, 1 H), 7.91 (s, 1 H), 7.85

_*** (d, J = 10.0 Hz, 1 H), 7.31 (m, 2H), 7.09 (d,

31 4.38 349.2 1 J = 10.0 Hz, 1 H), 6.78 (m, 1H), 4.18 (m,

(55) 2H), 3.54 (m, 2H), 3.42 (d, J = 6.5 Hz, 2H), 1.85 (m, 4H), 1.40 (m, 2H), 1.05 (m, 1 H), 0.50 (m, 2H), 0.33 (m, 2H).

CDCI3 δ δ 8.32 (s, 1 H), 7.85 (s, 1 H), 7.74

_*** (d, J = 9.9 Hz, 1 H), 7.30 (m, 2H), 6.85 (m,

32 2.37 408.2 1 1 H), 6.74 (d, J = 10.0 Hz, 1 H), 4.21 (m,

(82) 2H), 3.70 (m, 4H), 3.55 (m, 4H), 2.56 (m, 6H), 1.92 (m, 4H), 1.46 (m, 2H). CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in t [ +1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 8.24 (m, 1 H), 7.99 (s, 1 H), 7.83 (d, J = 10.0 Hz, 1H), 7.43 (m, 1 H), 7.33 (m, 1 H), 7.07 (d, J = 10.0 Hz, 1 H), 6.87 (dd, J =

33 4.69 363.2 1 ** 8.0, 1.5 Hz, 1 H), 4.15 (m, 2H), 3.54 (m,

2H), 3.38 (d, J = 6.5 Hz, 2H), 1.76 (m, 4H), 1.49 (m, 4H), 1.04 (m, 1H), 0.49 (m, 2H), 0.32 (m, 2H).

CDCIs δ 8.18 (m, 1 H), 7.81 (s, 1 H), 7.65 (d, J = 9.9 Hz, 1H), 7.28 (m, 2H), 6.85 (m, 1 H),

34 2.82 422.2 1 ** 6.67 (d, J = 9.9 Hz, 1 H), 4.12 (t, J = 7.2 Hz,

2H), 3.66 (m, 4H), 3.46 (m, 4H), 2.48 (m, 6H), 1.77 (m, 4H), 1.52 (m, 4H).

DMSO δ 8.50 (d, J = 2.4 Hz, 1 H), 7.91 (s, 1H), 7.87 (d, J = 10.0 Hz, 1 H), 7.31 (m, 2H), 7.13 (d, J = 10.0 Hz, 1H), 6.81 (m,

35 3.66 351.1 1 ** 1 H), 4.33 (t, J = 5.9 Hz, 2H), 3.89 (m, 2H),

3.81 (t, J = 5.9 Hz, 2H), 3.71 (m, 2H), 3.42 (d, J = 6.7 Hz, 2H), 1.01 (m, 1 H), 0.49 (m, 2H), 0.32 (m, 2H).

CDCI3 δ 8.43 (m, 1 H), 7.79 (m, 2H), 7.24 (m, 2H), 6.82 (m, 1H), 6.73 (d, J = 9.9 Hz,

36 1.84 _**

410.1 1 1H), 4.29 (m, 2H), 3.84 (m, 4H), 3.75 (m,

2H), 3.66 (m, 4H), 3.52 (t, J = 7.1 Hz, 2H), 2.49 (m, 6H).

DMSO δ 9.20 (s, 1 H), 7.98 (s, 1 H), 7.91 (m, 1 H), 7.86 (t, J = 4.5 Hz, 1H), 7.77 (d, J = 9.7 Hz, 1 H), 7.52 (m, 2H), 7.26 (t, J = 6.1

37 0.48 337.1 2 _**

Hz, 1 H), 6.67 (d, J = 9.7 Hz, 1 H), 3.41 (m, 2H), 3.28 (m, 2H), 2.78 (m, 2H), 2.59 (m, 2H), 2.25 (S, 3H).

DMSO δ 9.45 (s, 1 H), 8.02 (ms, 2H), 7.95

***

(m, 1 H), 7.76 (d, J = 9.7 Hz, 1 H), 7.54 (m,

38 5.12 413.1 2

(40) 2H), 7.29 (m, 6H), 6.67 (d, J = 9.7 Hz, 1H), 3.73 (s, 2H), 3.49 (m, 2H), 3.14 (m, 2H), 2.98 (m, 2H), 2.77 (m, 2H). CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in

t [M+1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 9.46 (s, 1 H), 8.47 (d, J = 5.7 Hz, 2Η), 8.12 (t, J = 5.1 Hz, 1 H), 8.03 (s, 1 H),

_*** 7.96 (m, 1H), 7.76 (d, J = 9.8 Hz, 1 H), 7.56

39 0.51 414.1 2 (m, 2H), 7.40 (d, J = 5.7 Hz, 2H), 7.20 (t, J

(46) = 6.4 Hz, 1 H), 6.65 (d, J = 9.4 Hz, 1 H), 3.78 (s, 2H), 3.44 (m, 2H), 3.19 (m, 2H), 3.00 (m, 2H), 2.80 (m, 2H).

DMSO δ 9.42 (s, 1H), 8.01 (s, 1 H), 7.95 (m, 2H), 7.76 (d, J = 9.7 Hz, 1 H), 7.54 (m,

40 0.31 420.3 2 * 2H), 7.21 (m, 1 H), 6.68 (d, J = 9.7 Hz, 1 H),

3.41 (m, 2H), 3.25 (m, 2H), 2.89 (m, 4H), 2.73 (m, 2H), 2.43 (m, 2H), 2.33 (m, 2H), 1.69 (m, 2H), 1.49 (m, 1 H), 0.92 (m, 2H).

DMSO δ 9.36 (s, 1H), 8.00 (s, 1 H), 7.93 (m, 2H), 7.77 (d, J = 9.7 Hz, 1 H), 7.53 (m,

41 0.30 392.4 2 _* 2H), 7.25 (t, J = 5.8 Hz, 1 H), 6.68 (d, J =

9.7 Hz, 1 H), 3.46 (m, 6H), 3.21 (m, 4H), 2.84 (m, 3H), 2.68 (m, 4H).

DMSO δ 9.30 (s, 1H), 8.39 (s, 1 H), 8.17 (m, 1H), 8.00 (s, 1 H), 7.93 (m, 1H), 7.78 (d,

42 0.33 366.3 2 _* J = 9.6 Hz, 1 H), 7.52 (m, 2H), 7.28 (m, 1 H),

6.69 (d, J = 9.7 Hz, 1 H), 3.50 (m, 2H), 3.29 (m, 2H), 2.87 (m, 4H), 2.74 (m, 4H).

CDCI3 δ 9.04 (m, 1 H), 7.86 (s, 1 H), 7.81 (m, 2H), 7.67 (d, J = 9.6 Hz, 1H), 7.52 (t, J = 7.8 Hz, 1H), 7.14 (m, 1H), 6.44 (d, J =

43 0.75 425.2 2 _**

9.6 Hz, 1 H), 4.87 (t, J = 6.5 Hz, 1 H), 3.67 (m, 2H), 3.56 (m, 4H), 3.47 (m, 4H), 3.33 (s, 3H), 3.03 (m, 2H), 2.85 (m, 4H).

DMSO δ 8.50 (m, 1H), 8.23 (s, 1 H), 7.95 (s, 1 H), 7.74 (d, J = 9.6 Hz, 1 H), 7.46 (d, J

_*** = 7.9 Hz, 1H), 7.34 (m, 1H), 7.28 (t, J =

44 0.37 310.2 2 6.0, 1 H), 6.88 (m, 1 H), 6.65 (d, J = 9.7 Hz,

(24) 1 H), 4.23 (m, 2H), 3.39 (m, 2H), 2.97 (t, J = 6.9 Hz, 2H), 2.83 (t, J = 5.9 Hz, 2H), 1.86 (m, 2H). CDK-8

Cpd. ¹H NMR (300 MHz; δ in ppm, J in t [M+1]⁺ Meth. IC50

Nr. Hz)

DMSO δ 8.21 (m, 1 H), 7.84 (d, J = 4.6 Hz,

*** 1 H), 7.73 (dd, J = 9.6, 2.3 Hz, 1H), 7.36 (m, 2H), 7.16 (m, 1 H), 6.99 (m, 1H), 6.67 (dd, J

45 3.95 378.1 1

(75) = 9.7, 2.8 Hz, 1 H), 4.18 (m, 2H), 3.32 (m, 2H), 3.11 (m, 2H), 2.97 (m, 2H), 2.79 (m, 2H), 1.70 (m, 9H).

DMSO δ 8.60 (s, 1H), 8.29 (s, 1 H), 7.83 (s, 1 H), 7.66 (d, J = 7.8 Hz, 1 H), 7.42 (t, J =

46 0.38 322.2 2 *

7.6 Hz, 1 H), 7.25 (d, J = 7.4 Hz, 1 H), 7.09 (t, J = 5.7 Hz, 1 H), 6.46 (s, 1 H), 3.95 (s, 2H), 3.27 (m, 2H), 2.68 (m, 2H), 2.42 (s, 3H), 1.69 (m, 4H), 1.48 (m, 2H).

Table 7: Cell Data. The following table demonstrates that representative compounds of the examples inhibit the transcriptional activity of β-catenine [EC50 values (nM)] driven by CDK8 in the cellular assay described hereinbefore.

Table 7

Claims

Claims

1. A compound of formula I,

wherein: ring A represents aryl or pyridyl, both of which are optionally substituted by one or more substituents selected from R⁴;

R¹ represents hydrogen or C _-6 alkyl optionally substituted by one or more substituents selected from E¹; X represents -C(H)= -C(Me)= or -N=;

Y represents a direct bond, -T¹-, -T²-C_1-2alkylene-, -C _-2alkylene-T³-, -0-N=C(H)- or -d^alkylene-, wherein the alkylene moieties are each independently substituted with one or more substituents selected from R⁵; each T , T² and T³ each independently represent a -0-, -C(O)-, -N(R¹⁰)-,

-C(0)N(R¹¹)- or -N(R¹²)C(0)-; each R², R³, R⁴ and R⁵ independently represent hydrogen or a substituent selected from halo, -CN, Rⁱ¹, -OR^j2, -SRⁱ³, -N(R^j )R^j5, -C(0)OR^j6 and -N(R^j7)C(0)R^j8; R^J1 , Rⁱ², R^j3, R^j4, R⁾⁵, R^j6, R^j7 and Rⁱ⁸ independently represent hydrogen or CMS (e.g. C _-4) alkyl optionally substituted by one or more substituents selected from halo and -OR^h; R^h represents hydrogen or 0_1-4 alkyl optionally substituted by one or more halo atoms;

Z represents -C_3-9alkylene-, -C_1-6alkylene-T⁴-C _-6alkylene-, -C(0)N(H)-, -N(H)C(0)-, -C_1-7alkylene-T⁵-, -T⁶-C_1-7alkylene- or -C_1-2alkylene-N(H)-C(0)- C_1-2alkylene-N(H)-, wherein the alkylene moieties are each optionally and independently substituted by one or more substituents selected from E²; each T⁴ represents -0-, -N(R¹³)-, -N(R¹ )-C(0)-, -C(0)-N(R¹⁵)-, -C(O)-, -cycloalkylene-T⁷-, -heterocycloalkylene-T⁷-, -arylene-T⁸- or -heteroarylene-T⁹-; each T⁵ and T⁶ independently represent -C(0)N(H)-, -N(H)C(0)-, -C(O)-, -cycloalkylene-T⁷-, -heterocycloalkylene-T⁷-, -arylene-T⁸- or -heteroarylene-T⁹-; the cycloalkylene, heterocycloalkylene, arylene and heteroarylene moieties are each optionally substituted by one or more substituents independently selected from E³; each T⁷, T⁸ and T⁹ independently represent a direct bond or -C(O)-; each R¹⁰, R¹¹ , R¹², R¹³, R¹⁴ and R¹⁵ independently represent hydrogen or C_1-12 alkyl optionally substituted by one or more substituents selected from E⁴; each E¹ , E², E³ and E⁴ independently represent:

(i) Q⁴;

(ii) Ci_-12 alkyl or heterocycloalkyl, both of which are optionally substituted by one or more substituents selected from =0 and Q⁵;

(iii) aryl or heteroaryl, both of which are optionally substituted by one or more substituents selected from Q⁶; any two E¹, E², E³ and/or E⁴ groups (for example on C _-12 alkyl groups, e.g. when they are attached to the same or adjacent carbon atoms, or, on aromatic groups, when attached to adjacent atoms), may be linked together to form a 3- to 12- membered ring, optionally containing one or more (e.g. one to three) unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from =0 and J¹; each Q⁴, Q⁵ and Q⁶ independently represent, on each occasion when used herein:

halo, -CN, -N(R²⁰)R²¹, -OR²⁰, -C(=Y¹)-R²⁰, -C(=Y¹)-OR²⁰, -C(=Y¹)N(R²⁰)R²¹, -C(=Y )N(R²⁰)-O-R^{2 a}, -OC(=Y )-R²⁰, -OC(=Y )-OR²⁰, -OC(=Y¹)N(R²⁰)R²¹, -OS(0)₂OR²⁰, -OP(=Y¹)(OR²⁰)(OR²¹), -OP(OR ⁰)(OR²¹), -N(R²²)C(=Y¹)R²¹, -N(R²²)C(=Y¹)OR²¹, -N(R²²)C(=Y )N(R²⁰)R²¹, -NR²²S(0)₂R²°, -NR²²S(O)₂N(R²⁰)R²¹, -S(O)₂N(R²⁰)R²¹, -SC(=Y¹)R²⁰, -SC(=Y )OR²⁰, -SC(=Y¹)N(R²⁰)R²¹, -S(0)₂R²⁰, -SR²⁰, -S(0)R²⁰, -S(0)₂OR²⁰, C_1-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from =0 and J²), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J³); each Y independently represents, on each occasion when used herein, =0, =S, =NR²³ or =N-CN; each R^{2 a} represents C _-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from J⁴ and =0), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J⁵); each R²⁰, R²¹, R²² and R²³ independently represent, on each occasion when used herein, hydrogen, C _-6 alkyl, heterocycloalkyi (which latter two groups are optionally substituted by one or more substituents selected from J⁴ and =0), aryl or heteroaryl (which latter two groups are optionally substituted by one or more substituents selected from J⁵); or any relevant pair of R , R and R , may (for example, when attached to the same atom, adjacent atom (i.e. 1 ,2-relationship) or to atoms that are two atoms apart, i.e. in a 1 ,3-relationship) be linked together to form (e.g. along with the requisite nitrogen atom to which they may be attached) a 4- to 20- (e.g. 4- to 12-) membered ring, optionally containing one or more heteroatoms (for example, in addition to those that may already be present, e.g. (a) heteroatom(s) selected from oxygen, nitrogen and sulfur), optionally containing one or more unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from J⁶ and =0; each J¹, J², J³, J⁴, J⁵ and J⁶ independently represents, on each occasion when used herein:

0) Q⁷;

(ii) C_1-6 alkyl or heterocycloalkyl, both of which are optionally substituted by one or more substituents selected from =0 and Q⁸; each Q⁷ and Q⁸ independently represents, on each occasion when used herein: halo, -CN, -N(R⁵⁰)R⁵¹, -OR⁵⁰, -C(=Y^a)-R⁵⁰, -C(=Y^a)-OR⁵⁰, -C(=Y^a)N(R⁵⁰)R⁵¹, -N(R⁵²)C(=Y^a)R⁵¹, -NR⁵²S(0)₂R⁵⁰, -S(O)₂N(R⁵⁰)R⁵¹, -N(R⁵²)-C(=Y^a)-N(R⁵⁰)R⁵¹, -S(0)₂R⁵⁰, -SR⁵⁰, -S(0)R⁵⁰, C_1-6 alkyl (optionally substituted by one or more fluoro atoms) or heterocyclalkyi (optionally substituted by one or more substituents selected from halo, -OR⁶⁰ and -N(R⁶ )R⁶²); each Y^a independently represents, on each occasion when used herein, =NR⁵³ or =N-CN; each R⁵⁰, R⁵¹, R⁵² and R⁵³ independently represents, on each occasion when used herein, hydrogen or C_L6 alkyl optionally substituted by one or more substituents selected from fluoro, -OR⁶⁰ and -N(R⁶ )R⁶²; or

any relevant pair of R⁵⁰, R⁵¹ and R⁵² may (for example when attached to the same or adjacent atoms) be linked together to form, a 3- to 8-membered ring, optionally containing one or more heteroatoms (for example, in addition to those that may already be present, heteroatoms selected from oxygen, nitrogen and sulfur), optionally containing one or more unsaturations (preferably, double bonds), and which ring is optionally substituted by one or more substituents selected from =0 and C_1-3 alkyl;

R⁶⁰, R⁶ and R⁶² independently represent hydrogen or C _-6 alkyl optionally substituted by one or more fluoro atoms; or a pharmaceutically acceptable ester, amide, solvate or salt thereof.

2. A compound as claimed in Claim 1 , wherein

Ring A represents phenyl or pyridyl (e.g. 3-pyridyl), both of which are optionally substituted by one or more substituents selected from R⁴;

preferably, ring A groups have a 1 ,3-linkage to the bicyclic core and Y group; more preferably still ring A represents one of the following groups:

wherein the squiggly lines represent the point of attachment to the bicyclic core and to the Y moiety, and the floating R⁴ substituent represents one or more R⁴ substituents attached to to relevant aromatic ring;

there is two or, preferably, none or one R⁴ substituent present on the A ring;

each R⁴ independently represents represents halo (e.g. fluoro or chloro), -OR^j2, -N(R^j4)R^j5 or -N(R^j7)C(0)R^j8;

R^j2, Rⁱ⁴, R^j5 and R^j7 independently represent hydrogen or C_1-4 alkyl (preferably unsubstituted);

R^j8 represents C_1-4 alkyl (preferably unsubstituted, e.g. methyl).

3. A compound as claimed in Claim 1 or Claim 2, wherein: R¹ represents hydrogen or Ci_-3 alkyl optionally substituted by one or more substituents selected from E¹; each R² and R³ independently represent hydrogen or R^j1; R^j represents C_1-2 alkyl (e.g. methyl; preferably unsubstituted); Y represents -T¹- or -C_1-2alkylene-T³-; each T¹ represents -O- or -N(R¹²)C(0)-; each T³ preferably represents -0-; Z represents -C_3-9alkylene-, -C^alkylene-T^-Cvealkylene- or -Ci_-7alkylene-T⁵-; more preferably, Z represents C₅alkylene, -C_Laalkylene-T - C_1-4alkylene-, or -C₃alkylene-T⁵-; each T⁴ represents -0-, -N(R¹³)- or -heterocycloalkylene-T⁷- (in which the het group is preferably a piperidinyl, e.g. 1 ,4-piperidinyl group); each T⁵ represents -N(H)C(0)-; T⁷ represents a direct bond or -C(O)-; and/or each R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and R ⁵ independently represent hydrogen or C _-4 alkyl optionally substituted by one or more substituents selected from E⁴.

4. A compound as claimed in any one of the preceding claims, wherein: E represents: (i) C_3-6 cycloalkyl (e.g. cyclopropyl) or a 5- or 6-membered heterocycloalkyl group (e.g. containing one or two heteroatoms, so forming e.g. a morpholinyl group), both of which are optionally substituted by one or more substituents selected from Q⁵ (but which are preferably unsubstituted); or (ii) aryl (e.g. phenyl) optionally substituted by one or more substituents selected from Q⁶; E⁴ represents: (i) Q⁴; (ii) acyclic C _-4 alkyl (e.g. methyl), C3.₆ cycloalkyl (e.g. cyclopropyl) or a 4-, 5- or 6-membered heterocycloalkyl group (e.g. containing one or two heteroatoms, so forming e.g. a morpholinyl, azetidinyl or piperidinyl group), both of which are optionally substituted by one or more substituents selected from Q⁵ (but which are preferably unsubstituted); or (iii) aryl (e.g. phenyl) optionally substituted by one or more substituents selected from Q⁶.

5. A compound as claimed in any one of the preceding claims, wherein: Q⁴ represents -N(R²⁰)R²¹ or -OR²⁰; Q⁶ represents halo (e.g. chloro or fluoro); R²⁰ and R² independently represent hydrogen or Ci_-3 alkyl optionally substituted by one or more substituents selected from J⁴; J⁴ represents Q⁷; Q⁷ represents -OR⁵⁰; R⁵⁰ represents hydrogen or preferably C_1-2 alkyl.

6. A compound of formula I as defined in any one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof, for use as a pharmaceutical.

7. A pharmaceutical formulation including a compound of formula I, as defined in any one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof, in admixture with a pharmaceutically acceptable adjuvant, diluent or carrier.

8. A compound, as defined in any one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof, for use in the treatment of a disease in which inhibition of CDK8 is desired and/or required.

9. Use of a compound of formula I, as defined in any one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof, for the manufacture of a medicament for the treatment of a disease in which inhibition of CDK8 is desired and/or required.

10. A compound as claimed in Claim 8 or a use as claimed in Claim 9, wherein the disease is cancer, immune disorders, cardiovascular diseases, viral infections, inflammation, metabolism/endocrine function disorders, neurological disorders and other associated diseases, and especially colon/colorectal cancer(s).

11. A method of treatment of a disease in which inhibition of CDK8 is desired and/or required, which method comprises administration of a therapeutically effective amount of a compound of formula I as defined in any one of Claims 1 to 5, or a pharmaceutically-acceptable ester, amide, solvate or salt thereof, to a patient suffering from, or susceptible to, such a condition.

12. A combination product comprising:

(A) a compound of formula I as defined in any one of Claims 1 to 5, or a pharmaceutically-acceptable ester, amide, solvate or salt thereof; and

(B) another therapeutic agent that is useful in the treatment of in the treatment of cancer and/or a proliferative disease,

wherein each of components (A) and (B) is formulated in admixture with a pharmaceutically-acceptable adjuvant, diluent or carrier.

13. A process for the preparation of a compound of formula I as defined in Claim 1 , which process comprises:

(i) reaction of a compound of formula II in which Z represents: -C_1-6alkylene-T⁴- C_1-6 alkylene, -C(0)N(H)-, -N(H)C(0)-, -C_1-7alkylene-T⁵-, -^"T-d.ralkylene- or -C_1-2alkylene-N(H)-C(0)-C_1-2alkylene-N(H)-, in which T⁴ represents -N(R ⁴)-C(0)- or -C(0)-N(R¹⁵)-; and T⁵ and T⁶ independently represent -C(0)N(H)- or -N(H)C(0)-, by

wherein Z¹ represents -C₁.₆alkylene-C(0)OH, -C _-6alkylene-N(R¹⁴)H, -C(0)OH, -NH₂, -C_1-7alkylene-C(0)OH, -C_1-7alkylene-NH₂, -C_1-2alkylene-NH₂, and Z² respectively represents HN(R ⁵)-Ci.₆alkylene-, HO(0)C-C_1-6alkylene-, H₂N-, HO(0)C-, H₂N-, HO(0)C- and HO(0)C-C_1-2alkylene-N(H)- (or derivatives thereof, such as carboxylic acid ester derivatives), and R , R², R³, R⁴, X, Y and ring A are as defined in Claim 1 ;

(ii) compounds of formula I in which Z represents: -C_1-6alkylene-T⁴-C_1-6 alkylene, in which T⁴ represents -O- or -N(R¹³)-, intramolecular reaction of a compound of formula III,

wherein Z³ represents -C _-6alkylene-OH, -C_1-6alkylene-N(R¹³)H or -C_1-6alkylene-L^x (in which L is a suitable leaving group), and Z⁴ represents L^y-C_1-6alkylene-, HO-C_1-6alkylene- or H(R¹³)N-C_1-6alkylene (as appropriate), and R¹, R², R³, R⁴, X, Y and ring A are as defined in Claim 1 ;

(iii) for compounds of formula I in which Y represents -T¹- or -T²-C _-2alkylene-, in which T¹ and T² independently represent -O- or -N(R¹⁰)- and Z represents -C₃-₉alkylene-, -C_1-6alkylene-T⁴-C_1-6alkylene-, -N(H)C(0)- or -T⁶-C_1-7alkylene-, intramolecular reaction of a compound of formula IV,

wherein Y^x represents HO-, HN(R¹⁰)-, HO-C_1-2alkylene- or HN(R ⁰)-Ci-₂alkylene-, Z⁵ represents -C₃.₉alkylene-L , -C_1-6alkylene-T⁴-C_1-6alkylene-L , -N(H)C(0)-L^x or -T^d.ralkylene-L", and L^x (a suitable leaving group), R¹, R², R³, R⁴, X, Y and ring A are as defined above or in Claim 1 ;

(iv) for compounds of formula I in which Y represents -T¹- or -T²-C _-2alkylene-, in which T¹ and T² independently represent -C(0)N(R¹¹)- or -N(R¹²)C(0)- and Z represents -C₃.₉alkylene-, -C_1-6alkylene-T -C _-6alkylene- or -T⁶-C _-7alkylene-, intramolecular reaction of a compound of formula V,

wherein Y^y represents HO(0)C-, HN(R¹¹)-, HO(0)C-C_1-2alkylene- or HN(R ¹)-C_1-2- alkylene-, Z⁶ represents -C₃-₉alkylene-N(R )H, -C₃.₉alkylene-C(0)OH, -C_1-6alkylene-T⁴-C₁.₆alkylene-N(R¹ )H or -C^alkylene-T^C^alkylene-CiC OH, and R¹, R², R³, R⁴, X, Y and ring A are as defined in Claim 1 ;

(v) for compounds of formula I in which R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and/or R¹⁵ represent optionally substituted C _-i2 alkyl, reaction of a corresponding compound of formula I in which R¹⁰, R ¹, R¹², R¹³, R¹⁴ and/or R¹⁵ represent hydrogen, with a compound of formula VI,

L¹-R¹⁰-¹⁵ VI

wherein R^10"15 represents R¹⁰, R¹¹, R¹², R ³, R ⁴ or R¹⁵ (as appropriate/required) and L represents a suitable leaving group, or with a compound of formula VII,

H(O)C-R^10a- ^5a VII

wherein R^10a- ^5a represents C _-5 alkyl optionally substituted by one or more halo atoms, under reductive amination reaction conditions; ( i) for compounds of formula I containing a -N(R¹⁰)-CH₂- or -N(R¹³)-CH₂- moiety, reduction of a corresponding compound of formula I containing a -C(0)N(R¹¹), -N(R¹²)C(0)-, -N(R¹⁴)C(0)- or -C(0)N(R¹⁵) moiety.

14. A process for the preparation of a pharmaceutical formulation as defined in Claim 7, which process comprises bringing into association a compound of formula I, as defined in any one of one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof with a pharmaceutically- acceptable adjuvant, diluent or carrier.

15. A process for the preparation of a combination product as defined in Claim 12, which process comprises bringing into association a compound of formula I, as defined in any one of Claims 1 to 5, or a pharmaceutically acceptable ester, amide, solvate or salt thereof with the other therapeutic agent that is useful in the treatment of cancer and/or a proliferative disease, and at least one pharmaceutically-acceptable adjuvant, diluent or carrier.