NL1007077C2 - Method for the recovery of a ß-lactam antibiotic. - Google Patents

Description

- 1 - PN 9289 PROCESS FOR THE EXTRACTION OF A FI-LACTAM ANTIBIOTIC 5

The invention relates to a method for recovering a β-lactam antibiotic from a mixture containing mainly β-lactam antibiotic and D-phenylglycine (FG) 10 in solution, the mixture remaining at a concentration such that FG remains in solution a pH is brought between 3 and 8, the obtained solid β-lactam antibiotic is recovered and the residual liquid is subjected to a concentration step whereby a slurry is formed with solid β-lactam antibiotic and solid FG, the slurry is brought to a pH where the β-lactam antibiotic dissolves, FG is separated as a solid, and the β-lactam antibiotic present in the mother liquor is at least partly used.

In the preparation of β-lactam antibiotics in which a β-lactam core is acylated with a D-phenylglycine derivative, recovery of the β-lactam antibiotic and work-up of the reaction mixture is generally difficult. Often the work-up is associated with significant losses of valuable components, in particular the β-lactam antibiotic, partly as loss of solubility and partly due to degradation due to the limited stability of β-lactam antibiotics.

The invention now provides a new concept for the recovery of β-lactam antibiotics, in which the losses of β-lactam antibiotic are greatly reduced in a simple, industrially applicable method, and valuable D-phenylglycine is also recovered.

During the acylation reaction of the β-lactam core 35 with a suitable acylating agent, in particular an enzymatic acylation reaction with, for example, an amide of D-phenylclycine, for example D-phenylglycine amide (FGA) or an ester of D-phenylglycine, for example the methyl ester of D- phenylglycine (FGM), hydrolysis of the acylating agent and the β-lactam antibiotic takes place, resulting in D-phenylglycine (FG).

In addition to the β-lactam antibiotic and FG 5, the mixtures obtained after an acylation reaction may also contain, for example, unreacted β-lactam core and / or acylating agent, for example FGA or FGM. It has been found that the exact composition of the mixtures that can be used in the method of the invention is not particularly critical. Mixtures suitable for use in the method according to the invention are preferably mixtures containing 10-1500 mM, in particular 50-1000 mM, β-lactam antibiotic; 0-1500 mM, especially 0-1000 mM FG; 0-1000 mM, in particular 0-200 mM β-lactam nucleus and 0-1000 mM in particular 0-400 mM D-phenylglycine derivative.

If necessary, a mixture containing β-lactam antibiotic and FG is brought to a concentration and pH such that all components, in particular the mentioned components, optionally with the exception of the β-lactam antibiotic, are in solution. The pH can be high for this purpose, for example between 6.5 and 11, preferably between 7 and 9.5; as a layer are chosen, for instance between 0 and 3, preferably between 0.3 and 2. When the process is carried out on a large scale, it is preferred to opt for a more or less continuous work-up. By operating the dissolution continuously, the residence time at relatively high or low pH is shortened. If desired, any solid components still present can be separated, for example by filtration or ultrafiltration.

According to the invention, the mixture, which may still contain a solid β-lactam antibiotic, is first brought to a pH between 3 and 8, preferably between 4 and 7, whereby care is taken, for example by adding water, that the The concentration of the reactants, in particular FG, is such that, with the exception of the β-lactam antibiotic, they already remain in solution in 1: 7 in 70 7 7 * - 3 - or not supersaturated. Preferably, the concentration is chosen such that, after the mixture is brought to a pH between 3 and 8, the FG is supersaturated in the solution. The temperature 5 is not particularly critical and is for instance between -5 and 45 ° C, in particular between 0 and 25 ° C. When the FG concentration in the mixture is relatively high, a temperature is preferably maintained between 0 and 10 ° C. Indeed, it has surprisingly been found that under these conditions it is possible to realize a strong supersaturation of FG, without FG settling down. This made it possible to maintain relatively high concentrations, so that less volume is needed and less β-lactam antibiotic remains in solution.

Consequently, the β-lactam antibiotic is largely precipitated as a solid, after which it can be recovered.

However, it has been found that the amount of β-lactam antibiotic present in the mother liquor after recovery of the solid β-lactam antibiotic is still relatively high. The applicant has now found a method whereby it is possible to work up this liquid further and to further increase the yield of β-lactam antibiotic. According to the invention, the liquid is subjected to concentration. To avoid degradation of the β-lactam antibiotic and staining of the β-lactam antibiotic and the FG crystals, a relatively low temperature should be selected and the concentration step should be relatively short, while obtaining a not too viscous slurry and large, easily separable FG crystals, on the contrary, a relatively high temperature and a relatively long, gradual concentration procedure must be chosen. Surprisingly, it has been found possible to perform a concentration under such conditions that ampicillin degradation is drastically limited while the FG crystals are still relatively large and readily separable.

The temperature at which the concentration is carried out may, for example, be between 10 and 80 ° C, preferably between 20 and 60 ° C, in particular between 25 and 55 ° C. The duration of the concentration is, for example, between 10 minutes and 24 hours, preferably between 0.5 and 10 hours, in particular between 1 and 5 hours. The temperature at which the concentration is carried out and the duration of the concentration are thereby chosen such that, as a rule, at a higher temperature, a relatively shorter duration is chosen, and vice versa.

Concentration can take place, for example, by evaporation under reduced pressure or nanofiltration. For example, the evaporation can be carried out in a thin-film evaporator. It has been found that the wall can be easily kept clean and that there is little degradation of the β-lactam antibiotic. In addition, it has been found that the quality of the FG crystals is better when evaporated gradually, for example by passing the liquid suspension to be concentrated at a high flow rate over the evaporator, whereby the composition of the liquid gradually changes. A second possible embodiment of the concentration is an evaporative crystallizer, for example the (cascade of) circulation evaporators.

It has been found that the concentration can also be carried out very well using nanofiltration.

Surprisingly, it has been found that the flux through the membrane remains relatively high despite the fact that crystallization occurs during nanofiltration.

Membranes suitable for use in the concentration via nanofiltration are, for example, SeIRO MPT-10 (Membrane Products Kiryat Weizmann), WFN0505 (Stork Friesland) and Nanomax-50 (Millipore).

The concentration factor, ie the ratio between the volume before concentration and the i Q n 7 n 7 7 - - 5 - volume after concentration, can vary within wide limits and is preferably between 1 and 30, in particular between 3 and 20. The higher the concentration factor, the higher the return will be. Preferably, the concentration factor is chosen such that the salts formed during the entire process remain in solution. The skilled person can easily determine the optimum concentration factor in his specific case.

Preferably, the slurry obtained after the concentration step 10 is first subjected to a separation, into a clear liquid stream and a concentrated slurry, or into a clear liquid stream and a solid. The separation can be carried out with any separating equipment, for example a centrifuge or a filter. Since it is not necessary to separate the solids as solids, a decanter is preferably used. For example, the clear liquid stream can be vented, providing an easy way to prevent build-up of degradation products and salts. Since this purge current is relatively small, little β-lactam antibiotic is lost due to solubility losses.

During the concentration, both FG and β-lactam antibiotic are formed as a solid. It has been found that the solid FG formed at the concentration is readily filterable. Consequently, it turned out to be possible - partly since the concentration of β-lactam antibiotic is now relatively low - to gain FG by bringing the slurry to a pH, whereby the β-lactam antibiotic goes into solution 30 and FG does not, for example a pH between 6 , 5 and 11, preferably between 7 and 9.5, or between 0 and 3, preferably between 0.3 and 2; and then separating FG as a solid, for example, by filtration or centrifugation. Since the solid can now be rapidly separated, relatively little degradation of the β-lactam antibiotic takes place here, despite the high and low> 007077 -6-pH, respectively. If desired, the filtrate can then be recycled back into the process or otherwise reused.

The β-lactam antibiotic in said filtrate 5 can be recovered, for example, by crystallization using, for example, a pH shift. Another possibility is to return the filtrate as such to the mixture containing the β-lactam antibiotic and FG in solution.

The method of the invention can be suitably used in the preparation of β-lactam antibiotics which have a phenylglycine side tail, for example, cephalexin, ampicillin, cefaclor, pivampicillin, bacampicillin, talampicillin and cephaloglycine.

In principle, any β-lactam core can be used; in particular a β-lactam nucleus with the general formula (1) R 1 / Y \ 20 \ H2n - 1 \ z // - N. / o y '

25 * ^ 0H

wherein R0 represents H or an alkoxy group with 1-3 C atoms; Y represents CH2, O, S or an oxidized form of sulfur; Z stands for 30 vc "3 Ni X | 1 ^ / 'CH,, ^, or 35 where RL stands for, for example, H, OH, halogen, an alkoxy group with 1-5 C atoms, an alkyl group with 1-5 C- atoms, a cycloalkyl group with 4-8 C atoms, an aryl or a heteroaryl group with 6-10 C atoms, the groups optionally being substituted, for example, with a 10 C 70 7 7 ** - 7- alkyl-, a aryl, a carboxy or an alkoxy group with 1-8 C atoms; and wherein the carboxylic acid group may optionally be an ester group.

Suitable examples of β-lactam nuclei that can be used in the method according to the invention are penicillin derivatives, for example 6-aminopenicillanic acid (6-APA), and cephalosporin derivatives, for example a 7-aminocephalosporanoic acid with or without a substituent on the 3- site, for example, 7-10 aminocephalosporanic acid (7-ACA), 7-aminodesacetoxycephalosporanic acid (7-ADCA) and 7-amino-3-chloro-cef-3-em-4-carboxylic acid (7-ACCA).

In principle, any enzyme suitable as a catalyst in the coupling reaction can be used as the enzyme. Such enzymes are, for example, the enzymes known under the general term penicillin amidase or penicillin acylase. Such enzymes are described, for example, in J.G. Shewale et. al. Process Biochemistry, August 1989 p. 146-154 and in 20 J.G. Shewale et. al. Process Biochemistry International, June 1990, p. 97-103. Examples of suitable enzymes are enzymes derived from Acetobacter. in particular Acetobacter pasteurianum. Aeromonas. Alcaliaenes. in particular Alcaliaenes faecalis. Aphanocladium, Bacillus 25 sp., In particular Bacillus meaaterium, Ceohalosoorium. Escherichia. in particular Escherichia coli.

Flavobacterium, Fusarium. in particular Fusarium oxvsporum and Fusarium Solani. Kluvvera. Mvcoolana. Protaminobacter, Proteus. in particular Proteus 30 rettaari, Pseudomonas and Xanthomonas. in particular Xanthomonas citrii.

An immobilized enzyme is preferably used, since the enzyme can then be easily separated and reused. A suitable immobilization technology is described, for example, in EP-A-222462. Another suitable technology is formed by immobilizing the Penicillin G acylase on a support containing a gelling agent, for example, gelatin, and a polymer with free amino groups, for example, alginate amine, chitosan or polyethyleneimine. In addition, enzymes can also be used as a crystalline substance (Clecs).

For example, the immobilized enzymes commercially available have proved particularly suitable, the Escherichia coli enzyme from Boehringer 10 Mannheim GmbH commercially available under the name Enzygel®, the immobilized Penicillin-G acylase from Recordati and the immobilized Penicillin-G acylase from Pharma Biotechnology Hanover.

In the (enzymatic) acylation reaction, as acylating agent, for example, D-phenylglycine in activated form, preferably a (primary, secondary or tertiary) amide or salt thereof, or a lower alkyl (1-4C) ester, for example a methyl ester, can be used.

The temperature at which the enzymatic acylation reaction is carried out is usually below 40 ° C, preferably between -5 and 35 ° C. The pH at which the enzymatic acylation reaction is carried out is usually between 5.5 and 9.5, preferably between 6.0 and 9.0.

Preferably, the reaction is stopped almost completely when the maximum conversion has been reached. A suitable embodiment to stop the reaction is to lower the pH, preferably to a value between 4.0 and 6.3, in particular between 4.5 and 5.7. Another suitable embodiment is to lower the temperature of the reaction mixture once the maximum conversion has been reached. A combination of both embodiments is also possible.

After the reaction has virtually stopped upon reaching maximum conversion, the reaction mixture is usually present in the form of a slurry containing multiple solids, for example, the antibiotic, ο-*n, 7 7 7 1 * -9-phenylglycine and optionally immobilized enzyme. Due to the process economy, the immobilized enzyme is preferably recovered. This can conveniently be done, for example, by filtering the reaction mixture over a screen while stirring, preferably choosing the direction of rotation of the stirrer such that the suspension is pumped up in the center of the stirrer. Valuable components, for example the antibiotic and FG, can then be recovered with the method according to the invention, wherein the solid components, optionally apart from a solid antibiotic, are first dissolved, for instance by means of a ρΗ-shift.

For the purposes of the invention, a pH reduction can be effected, for example, by adding an acid to the mixture. Suitable acids are, for example, mineral acids, in particular sulfuric, hydrochloric or nitric acid. Hydrochloric acid is preferably used. For example, a pH increase can be accomplished by adding a base to the mixture. Suitable bases are, for example, inorganic bases, in particular ammonia, caustic potash or caustic soda. Ammonia is preferably used.

The enzymatic acylation reaction, and the work-up of the reaction mixture, are in practice usually carried out in water. If desired, the reaction mixture may also contain an organic solvent or a mixture of organic solvents, preferably less than 30% by volume. Examples of organic solvents that can be used are alcohols with 1-7 C atoms, for example a monoalcohol, in particular methanol or ethanol; a diol, especially ethylene glycol or a triol, especially glycerol.

The process according to the invention is particularly suitable for use in the work-up of the reaction mixture obtained after the 70%. 7-10 enzymatic acylation reaction in which 6-APA is acylated with an amide of D-phenylglycine, for example (FGA) or an ester of D-phenylglycine, for example FGM.

In a preferred embodiment, it is hereby ensured that the concentration of 6-APA in dissolved form present in the reaction mixture is kept relatively low, so that a higher conversion can be achieved than when the concentration of dissolved 6-APA is chosen as high as possible. Moreover, it has been found that the stirability of the reaction mixture is considerably better when the concentration of dissolved 6-APA is kept low.

In this context, conversion is understood to mean the molar ratio of ampicillin formed to the amount of 6-APA used. The concentration of dissolved 6-APA is expressed as the amount of 6-APA in moles per kg of reaction mixture; the total concentration, dissolved and undissolved, 6-APA and ampicillin is expressed as the amount of 6-APA plus ampicillin in moles per kg of total reaction mixture; the total reaction mixture may contain a number of solids in addition to the solution, for example 6-APA, ampicillin, phenylglycine and immobilized enzyme.

The molar ratio of acylating agent to 6-APA, i.e. the total amount of phenylglycine derivative added divided by the total amount of 6-APA added, expressed in moles, is preferably less than 2.5. The molar ratio is preferably between 1.0 and 2.0, in particular between 1.2 and 1.8.

The enzymatic acylation reaction is preferably carried out as a batch process. If desired, it is also possible to carry out the reaction continuously, in line controlling the concentration of dissolved 6-APA.

The total concentration of 6-APA plus ampicillin (in dissolved and undissolved form) in the reaction mixture is preferably higher than 250 mM, more preferably higher than 300 mM, in particular higher than 70 7 7 - 11 - 350 mM chosen.

The concentration of dissolved 6-APA is kept in this preferred form during the preparation of ampicillin, because of the increased instability of 6-APA at higher concentrations of 6-APA in solution, preferably below 300 mM, especially below 250 mM . At a higher concentration of the acylating agent, a higher concentration of dissolved 6-APA can optionally be chosen than at a lower concentration. Namely, at a higher concentration of the acylating agent, the reaction speed is higher, as a result of which 6-APA is only present in high concentration in dissolved form for a relatively short time.

The concentration of 6-APA in dissolved form present in the reaction mixture can be kept low in various ways. One possibility to keep the concentration of dissolved 6-APA low is to present only part of the total amount of 6-APA and dose the rest during the reaction. A drawback of this, however, is that 6-APA must then be dosed as a solid, which results in 20 practical drawbacks. Preferably, therefore, the total amount of 6-APA in a batch process is presented at the beginning of the reaction, after which the concentration of 6-APA in the reaction mixture will decrease and the concentration of 25 ampicillin will increase during the enzymatic acylation reaction. A suitable method to still achieve a low concentration of dissolved 6-APA is, for example, by keeping the pH at a lower value compared to the pH value, whereby a maximum solubility of the reactants is achieved. A particularly suitable method for keeping the 6-APA concentration in dissolved form low is, for example, by ensuring that the concentration of the phenyl glycine derivative is kept low, for example by partially dosing the phenyl glycine derivative in the course of the reaction.

Namely, it has been found that when the phenylglycine derivative concentration is kept low, little 6-APA goes into solution, so that the concentration of 6-APA in solution can be controlled by dosing the phenylglcyine derivative.

A particularly suitable embodiment is obtained when FGA is added in the form of a salt thereof, preferably the salt of FGA and a mineral acid, for example FGA.HCl, FGA.1 / 2H2SO4 and FGA.HN03. Namely, in this way it is simply possible to achieve an optimum dosage of the FGA by keeping the pH constant. Preferably FGA.1 / 2H2SO4 is used because this salt has a very high solubility.

Within the scope of this invention, the different components may be present in the reaction mixture in the free form or as salts. The said pH value always means the pH value measured at room temperature.

The invention will be further elucidated on the basis of the examples, without, however, being limited thereto.

Abbreviations: AMPI = ampicillin 25 AMPI.3H20 = ampicillin trihydrate 6-APA = 6-amino-penicillanic acid FGA = D-phenylglycine amide FG = D-phenylglycine FGHM = Dp-hydroxyphenylglycine methyl ester 30 Assemblase ™ is an immobilized Escherichia colylaseicillicillin coli ATCC 1105 as described in WO-A-97/04086. The immobilization has been performed as described in EP-A-222462, using gelatin and chitosan as gelling agent and glutaraldehyde as crosslinker.

The final activity of the Escherichia 1007077 * - 13 - coli penicillin acylase is determined by the amount of enzyme added to the activated beads and was 3 ASU / g dry weight with 1 ASU (Amoxicillin Synhesis Unit) defined as the amount of enzyme 5 per hour generates 1 g of Amoxicillin.3H20 from 6-APA and FGHM (at 20 ° C; 6.5% 6-APA and 6.5% FGHM).

Example I

Preparation of FGA.1 / 2H2SO4 solution.

301.6 g FGA (2.00 mol) was suspended in 650 g water at T = 5 ° C. 102.1 g of 96% H 2 SO 4 (1.00 mol) was added dropwise with stirring over 1 hour, the temperature being kept at T <25 ° C by cooling.

Example II

Enzymatic synthesis of ampicillin.

An enzyme reactor (1.5 l, diameter 11 cm), equipped with a sieve bottom with 175 μ g mesh, was charged with 300 g net wet assemblase ™ (the term net wet 20 refers to the mass of the enzyme obtained after the enzyme has been separated from an enzyme slurry with a glass filter).

A production reactor (1.2 L) was charged with 131.6 g of 6-APA (0.600 mol), 30.2 g of FGA (0.200 mol) and 400 ml of water (T = 10 ° C). This mixture was stirred at T = 10 ° C for 15 minutes and then transferred to t = 0 in the enzyme reactor using 100 ml of water (T = 10 ° C).

The stirrer was turned on in the enzyme reactor at t * 0. The temperature was always kept at 10 ° C.

For 233 minutes, 423.7 g (0.800 mol) of FGA.J $ H 2 SO 4 solution (from Example I) was added at a constant rate. The pH was kept constant at ca.

6.3. From t = 295 minutes, the pH was kept at 6.3 by titration with 6N H 2 SO 4. At t = 570 minutes, the amount of AMPI was maximal and the pH was lowered to 5.0 by adding 6N H 2 SO 4. The enzyme reactor 1007077 <- 14 - now contained:

575 mmol AMPI

15 mmol 6-APA

50 mmol FGA

5 365 mmol FG

Example III

Separation of the AMPI / FG slurry from the enzyme reactor.

Using stirring filtration, the 10 AMPI / FG slurry prepared as described in Example II was removed from the enzyme reactor via the sieve bottom. An angled-blade agitator was used, which was placed 0.5 cm above the sieve. Stirred at about 500 rpm. The reactor was rinsed with 10 250 ml portions of water (T = 10 ° C). The wash waters were also removed through the sieve bottom with stirring filtration.

The AMPI / FG slurry separated from the reactor and all washings were combined (T = 10 ° C). The resulting AMPI / FG slurry contained> 99.8% of the total 20 AMPI produced in the enzyme reactor and> 99.5% of the total FG produced.

After this stirring filtration, the Assemblase ™ was> 99.5% in the enzyme reactor.

Example IV

Concentrate the ampicillin mother liquor by evaporation using a thin film evaporator.

A mother liquor from an AMPI crystallization (amount: 6798 g, T = 5 ° C, pH = 6.0) contained 0.06% (17 30 mmol) 6-APA, 0.10% (45 mmol) FGA, 0 , 53% (104 mmol) AMPI and 0.96% (430 mmol) FG.

This mother liquor was concentrated by evaporation using a thin film evaporator. The feed to the thin film evaporator was added from a storage vessel, and the product of the thin film evaporator was returned to the same storage vessel. The 10 0! 11-15 storage vessel was stirred.

The wall temperature of the thin film evaporator was set at t = 65 ° C and the pressure in the thin film evaporator was set at P = 80 mbar.

The circulation was started at t = 0 (storage vessel - »thin film evaporator -» storage vessel; flow = 41.6 kg / hour).

The temperature of the liquid in the storage vessel was kept at T = 40 ° C.

The evaporation was stopped at t = 257 minutes. A total of 5655 g of condensate was now collected. The contents of the thin film evaporator and storage vessel were circulated for an additional 2 hours, while the temperature was lowered linearly from T = 40 ° C to T = 3 ° C. The concentrate (1084 g) was then drained. The thin film evaporator and the storage vessel were rinsed successively with 250 ml and 2000 ml of water (T = 10 ° C). The concentrate and the washing water were combined. The 2nd wash water contained negligible amounts of AMPI and FG.

Example V

Return of the concentrated ampicillin mother liquor as a recycle in the ampicillin process; secretion of FG.

The combined concentrate + 1st wash water (Example IV) was filtered through a glass filter (diameter 10 cm, filtration time 10 minutes). The solid was rinsed with 25 ml of water (T = 5 ° C). Yield: 210 g of AMPI / FG wet cake. The mother liquor (1155 g) was drained.

The AMPI / FG wet cake was quantitatively transferred to a stirred reactor using 400 g of water. The slurry was stirred at T = 5 ° C for 1 hour. 33.0 g of 6N HCl were then added at T = 5 ° C over 4 minutes. After stirring for 5 minutes, the slurry was filtered through a glass filter (diameter 13 cm, filtration time 5 minutes). The FG wet cake was washed with 120 ml of water (T 35 = 5 ° C) and dried. Yield = 36.7 g FG. The mother liquor and wash water were combined (T = 5 ° C) and added after 2 1007077-16 minutes to the acidic solution of Example VI (over 30 minutes).

Example VI

5 Ampicillin recrystallization, including recycling of the concentrated ampicillin mother liquor.

The recrystallization was carried out in an arrangement which consisted successively of a Vooxxa vessel (4 L), a dissolving vessel (0.25 L), a filter 10 fitted with a Seitz filter plate, and a crystallization vessel (7 L). All vessels were equipped with a stirrer, a pH electrode and a thermometer.

In the crystallization vessel, 200 ml of water (T = 5 ° C) with 5.0 g of AMPI.3H20 as a seed was introduced. The pH was adjusted to pH 7.0 with 2N NaOH solution.

The AMPI / FG slurry, isolated as described in Example III, was quantitatively transferred to the storage vessel, and cooled to T = 2 ° C with stirring. After the entire line was brought to T = 2 ° C, the dissolution vessel was filled from the storage vessel. At t = 0, the pH in the dissolution vessel was adjusted to pH = 1.1 using 6N HCl, after which the pH was kept at 1.1 (titration using 6N HCl). Subsequently, the contents of the storage vessel were added to the dissolving vessel in 1 hour, while the contents of the dissolving vessel were dosed to the crystallization vessel, always keeping the level in the dissolving vessel constant. The temperature in the crystallization vessel was kept at T = 5 ° C. The pH in this vessel was kept at pH = 7.0 by titration with 2N NaOH solution. In addition, the combined mother liquor and wash water, which were prepared as described in Example V, were added to the dissolution vessel at a constant rate from t = 15 minutes to t = 45 minutes.

The storage vessel was empty at t = 60 minutes and a total of 300 ml of 6N HCl solution was added to the dissolution vessel 1 7 7 7 17-17. The storage vessel was rinsed to the dissolution vessel with 450 g of water (T = 5 ° C). Titration with 6N HCl was stopped. The dissolution vessel was rinsed to the crystallization vessel with 50 g of water (T = 5 ° C). The pH in the crystallization vessel was lowered to 6.0 using 6N HCl. After stirring for 1 hour, the slurry in the crystallization vessel was filtered over a glass filter, and the wetcake was washed with 2x 175 ml of water (T = 5 ° C) and dried. Yield: 10 227 g AMPI.3H20 (incl. Graft), so 222 g AMPI.3H20 (excl. Graft), ie 92% AMPI.3H20 compared to 600 mmol 6-APA.

1ÜÜ7U 77 «

Claims (18)

A method for recovering a β-lactam antibiotic from a mixture containing the β-lactam 5 antibiotic and D-phenylglycine (FG) in solution, the mixture at a concentration such that FG remains in solution, at a pH between 3 and 8 is brought, the obtained solid β-lactam antibiotic is recovered and the remaining liquid is subjected to a concentration step whereby a slurry is formed with solid β-lactam antibiotic and solid FG, the resulting slurry is brought to a pH where the β -lactam antibiotic dissolves, FG is separated as a solid, and the β-lactam antibiotic present in the mother liquor is at least partly used. A method according to claim 1, wherein the concentration of the mixture is selected such that, after the mixture is brought to a pH between 3 and 8, the FG is supersaturated in the solution. A method according to claim 1 or 2, wherein the β-lactam antibiotic present in the mother liquor is at least partly recovered. A method according to any one of claims 1-3, wherein the mother liquor is recycled and combined with the mixture. 5. A method according to any one of claims 1-4, wherein the concentration is carried out at a temperature between 20 and 60 ° C for 0.5-10 hours. The method of claim 5, wherein the concentration is carried out at a temperature between 25 and 55 ° C for 1-5 hours. 7. A method according to any one of claims 1-6, wherein the concentration is carried out in a thin film evaporator. 1 Π 0 7 n 7 7 - - 19 - A method according to any one of claims 1-7, wherein the concentration factor during the concentration is between 3 and 20. 9. A method according to any one of claims 1-8, wherein the slurry is first subjected to a separation in a liquid stream and a concentrated slurry or a solid. The method of claim 9, wherein the separation is performed in a decanter. A method according to any one of claims 1-10, wherein the starting mixture mainly containing β-lactam antibiotic and FG comes from an enzymatic acylation reaction in which the corresponding β-lactam core is acylated with a The method of claim 11, wherein the mixture obtained after the acylation reaction is first subjected to a pH change to a pH between 6.5 and 11, or a pH between 0 and 3. The method of claim 12, wherein the mixture is subjected to a pH drop to a pH between 0.3 and 2. The method of any one of claims 1 to 13, wherein the mixture is 10-1500 mM β-lactam antibiotic, 0-1500 mM 25 contains FG, 0-1000 mM D-phenylglycine derivative and 0-1000 mM β-lactam nucleus. The method of any one of claims 1 to 14 wherein the β-lactam core is 6-aminopenicillanic acid (6-APA) and the β-lactam antibiotic is ampicillin. D-phenylglycine derivative. The method of any one of claims 1 to 14, wherein the β-lactam nucleus is 7-aminodesacetoxycephalosporanic acid (7-ADCA) and the β-lactam antibiotic is cephalexin. The method of any one of claims 1 to 14, wherein the β-lactam core is 7-amino-3-chloro-cef-3-em-4-carboxylic acid (7-ACCA) and the β-lactam antibiotic is cefaclor. - 20 - 18. Method for the recovery of a β-lactam antibiotic as described and illustrated by the examples. 1007077 COOPERATION TREATY (PCT) REPORT ON NEWNESS RESEARCH OF INTERNATIONAL TYPE 10 IDENTIFICATION OF NATIONAL APPLICATION I Characteristic of o: applicant o »of the gemnugoe | j 9289EN Neo-Tanosis application no. 1 after tenngsoaojm 1007077 September 19, 1997 ______I _ Invoked priority date -------: --—-—-— -! Applicant (Name) j CHEMFERM V.O.F. j Danjm of the request for an investigation of intemonal type Ooor oe Insanoe for Intemasonaai Unquestion (ISA) to a request for an investigation of intemaDonaaJ type known nr SN 29945 NL I. CLASSIFICATION OF THE SUBJECT (if different deassessments apply. (dassificaoe symbols) According to oe interna Donate dassilicaoe (IPC) Int.Cl. 6: C 07 D 499/18, C 07 D 501/12, C 12 P 37/04, C 12 P 35/04 II. FIELDS OF TECHNIQUE EXAMINED __Onoerzocitte minimum documentation__ Classification system 1 Classificane symbols _ ^ __] Int.Cl · 6: C 07 D, C 12 P, A 61 K _1__ Unsourced anoere oocumenaoe o an oe minimum oooumenaoe insofar as such documents are included in the prayers examined I recorded yy - - yy HI. I_i NO RESEARCH EQUAL FOR CERTAIN CONCLUSIONS (comments on supplement sheet) | IV. LACK OF UNITY OF INVENTION (cpmerxmgen on supplementincsolad)! rorr CT / 1SA, 201: 3I: E 7