IE57726B1 - Improvements in or relating to cephalosporins - Google Patents
Improvements in or relating to cephalosporinsInfo
- Publication number
- IE57726B1 IE57726B1 IE1938/84A IE193884A IE57726B1 IE 57726 B1 IE57726 B1 IE 57726B1 IE 1938/84 A IE1938/84 A IE 1938/84A IE 193884 A IE193884 A IE 193884A IE 57726 B1 IE57726 B1 IE 57726B1
- Authority
- IE
- Ireland
- Prior art keywords
- cefuroxime
- admixture
- solvent
- minutes
- stirred
- Prior art date
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Classifications
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D501/00—Heterocyclic compounds containing 5-thia-1-azabicyclo [4.2.0] octane ring systems, i.e. compounds containing a ring system of the formula:, e.g. cephalosporins; Such ring systems being further condensed, e.g. 2,3-condensed with an oxygen-, nitrogen- or sulfur-containing hetero ring
- C07D501/14—Compounds having a nitrogen atom directly attached in position 7
- C07D501/16—Compounds having a nitrogen atom directly attached in position 7 with a double bond between positions 2 and 3
- C07D501/20—7-Acylaminocephalosporanic or substituted 7-acylaminocephalosporanic acids in which the acyl radicals are derived from carboxylic acids
- C07D501/24—7-Acylaminocephalosporanic or substituted 7-acylaminocephalosporanic acids in which the acyl radicals are derived from carboxylic acids with hydrocarbon radicals, substituted by hetero atoms or hetero rings, attached in position 3
- C07D501/38—Methylene radicals, substituted by nitrogen atoms; Lactams thereof with the 2-carboxyl group; Methylene radicals substituted by nitrogen-containing hetero rings attached by the ring nitrogen atom; Quaternary compounds thereof
- C07D501/46—Methylene radicals, substituted by nitrogen atoms; Lactams thereof with the 2-carboxyl group; Methylene radicals substituted by nitrogen-containing hetero rings attached by the ring nitrogen atom; Quaternary compounds thereof with the 7-amino radical acylated by carboxylic acids containing hetero rings
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D501/00—Heterocyclic compounds containing 5-thia-1-azabicyclo [4.2.0] octane ring systems, i.e. compounds containing a ring system of the formula:, e.g. cephalosporins; Such ring systems being further condensed, e.g. 2,3-condensed with an oxygen-, nitrogen- or sulfur-containing hetero ring
- C07D501/14—Compounds having a nitrogen atom directly attached in position 7
- C07D501/16—Compounds having a nitrogen atom directly attached in position 7 with a double bond between positions 2 and 3
- C07D501/20—7-Acylaminocephalosporanic or substituted 7-acylaminocephalosporanic acids in which the acyl radicals are derived from carboxylic acids
- C07D501/24—7-Acylaminocephalosporanic or substituted 7-acylaminocephalosporanic acids in which the acyl radicals are derived from carboxylic acids with hydrocarbon radicals, substituted by hetero atoms or hetero rings, attached in position 3
- C07D501/26—Methylene radicals, substituted by oxygen atoms; Lactones thereof with the 2-carboxyl group
- C07D501/34—Methylene radicals, substituted by oxygen atoms; Lactones thereof with the 2-carboxyl group with the 7-amino radical acylated by carboxylic acids containing hetero rings
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
- A61P31/04—Antibacterial agents
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Communicable Diseases (AREA)
- Pharmacology & Pharmacy (AREA)
- Oncology (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Cephalosporin Compounds (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Abstract
A process for obtaining highly pure crystalline cefuroxime axetil comprises crystallising cefuroxime axetil from a solution thereof in an organic or aqueous solvent or a mixture thereof and then drying and isolating the product. Preferred solvents are alkyl acetates in admixture with ethers or aliphatic or aromatic hydrocarbons. The higher the yield from crystallisation, the closer to a 1:1 stoichiometric ratio of R:S isomers the product will contain, this being most desirable for an antibiotic product which is to be administered orally.
Description
Improvements in or relating to cephalosporins This invention relates to improvements in or relating to cephalosporins. More particularly it relates to improvements in the manufacture of cefuroxime 1-acetoxyethyl ester (cefuroxime axetil).
The compound (6R,7R)-3-carhamoyloxymethyl7-1(Z)-2-(fur-2-yl)-2-methoxyiminoacetamido]ceph3-em-4-car boxy lie acid has the approved name sscefuroxime This compound is a valuable antibiotic characterised by high broad spectrum activity against.gram-positive and gram-negative microorganisms, this property being enhanced by the very high stability of the compound to β-lactamases produced by a range of gram-negative microorganisms. It is well tolerated in the mammalian body and is used widely as an antibiotic in clinical practice. Cefuroxime and its. salts are principally of value as injectable antibiotics since they are poorly absorbed from the gastro-intestinal tract and are therefore present in sera and urine only in low concentrations after oral administration. There has therefore been a need for a form of cefuroxime which is capable of being absorbed from the gastro-intestinal tract following oral administration.
We have found that appropriate ester ificatIon of the carboxyl group of cefuroxime improves the effectiveness on oral administration. The presence of such an appropriate esterifying group results in significant absorption of the compound from the gastro-intestinal tract, whereupon the esterifying group is hydrolysed by enzymes present in, for example, serum and body tissues to yield the antibiotically active parent acid. To be effective upon oral administration the ester must be stable enough to reach the site of absorption without significant degradation, must be sufficiently absorbed upon reaching the appropriate site, and must be sufficiently susceptible to hydrolysis by systemic esterases for the parent acid to be liberated within V a short time of the ester being absorbed. British Patent Specification No. 1571683 discloses and claims a number of esters of cefuroxime as having properties rendering them of significant potential value as orally administrable antibiotics.
Of the esters described in British Patent Specification No, 1571683, we have found cefuroxime axetil to be of particular interest. This product possesses an asymmetric carbon atom at .the 1-position of the 1-acetoxyethyl group and can therefore exist in the form of R and S isomers or mixtures thereof.
The processes for the preparation of the above ester exemplified in British Patent Specification No. 1571683 produce the material either in relatively impure amorphous form or in the form of a crystalline material. Furthermore, the crystalline material produced by the methods described in this specification generally contains a predominance of either the R or the S isomer whereas an approximately 1:1 ratio is advantageous for administration. The crystalline product is not therefore ideally suited to administration.
We have now been able to develop a process whereby cefuroxime axetil may be obtained in highly pure crystalline form and in high yield. Such a product is not only useful from the point of view of being a highly pure form of the active compound and hence more suitable for biological administration but, more particularly, is also highly useful as a starting material for the preparation of a highly pure, substantially amorphous form of cefuroxime axetil, which form we have surprisingly found has high bioavailability upon oral administration and a better balance of properties for commercial use than the crystalline material. The amorphous cefuroxime axetil which has these properties is desirably an approximately 1:1 ratio of R to S isomers since this has been found to be of value ·/ in maximising the solubility in aqueous media of the amorphous product, and the process we have developed can provide crystalline cefuroxime axetil having this approximate ratio of isomers.
Accordingly, we provide a process for the preparation of highly pure crystalline cefuroxime axetil in high yield which comprises crystallising cefuroxime axetil from a solution thereof in an organic or aqueous solvent or a mixture thereof, isolating and drying the product.
The choice of crystallisation solvent has been found important if the yield is to be maximised and the R to S isomer ratio of the product is to be, as is desirable, approximately 1:1, for example in the range 0.9:1 to 1.1:1. We have found the different isomers of cefuroxime axetil to have different solubilities, one of them being consistently more soluble than the other. The levels of solubility vary according to the solvent, and so a solvent system will desirably be chosen which allows a practically quantitative recovery of the cefuroxime axetil that is present prior to crystallisation, thereby assuring an approximately 1:3. ratio of isomers .
The solvent system from which the product may be crystallised will desirably be selected from an ester, for example methyl or ethyl acetate, or a halogenated hydrocarbon such as methylene chloride, optionally but preferably in admixture with an ether, for example diisopropyl ether or an aliphatic or aromatic hydrocarbon, for example petroleum ether or toluene; or an alcohol, for example ethanol or isopropanol, optionally but preferably in admixture with water, such as in aqueous industrial methylated spirit; or an amide, such as dimethylformamide or dimethylacetamide, or ketone, such as acetone, in admixture with water . r The crystallisation step will desirably be carried out at ambient temperature, for example γ at from about 10 to 30°C and the concentration of the cefuroxime axetil in the solution from which crystallisation will occur will generally be adjusted e.g. by evaporation of solvent or by dilution so as to be neither too dilute nor too concentrated respectively. The crystallisation may comprise the last stage or stages of a reaction .in which the cefuroxime axetil is formed. In such a case, the initial stage of crystallisation may occur at quite a high temperature, e.g. up to about 65°C, but in order to maximise the yield and obtain a suitable ratio of isomers in the product, a temperature range of from 10 to 30° is preferred for the. final isolation.
The reaction in which the cefuroxime axetil is formed will preferably be an esterification reaction carried out in the manner described in British Patent Specification No. 1,571,683 and using a highly pure sodium cefuroxime starting material. A preferred reagent for the esterification is 1-acetoxyethyl bromide and in order to produce an approximately 1:1 ratio of R and S isomers prior to recrystallisation, it is clearly preferred that such a reagent be racemic.
The preferred sodium cefuroxime starting material will generally be itself highly pure.
Such a material may be obtained inter alia, by reaction of (6R,7R)-3-hydroxymethyl~7-[Z-2~(fur2-yl)-2-methoxyiminoacetamido]ceph-3-em~4-carboxylie acid with chlorosulphonyl isocyanate in an alkyl acetate as solvent at a temperature of from -25° to +10°C, followed by hydrolysis in situ at a temperature of +10 to +30°C and crystallisation following addition of sodium 2-ethylhexanoate in acetone or methyl acetate as solvent. Such a material will generally have a purity level of 90% mass/mass (m/m) or greater.
The eefuroxime axetil produced by the process of this invention has an R to S isomer mole ratio of approximately 1:1, and is generally not less than 95% m/m pure (uncorrected for residual solvents).
In its highly pure, crystalline form the 10 eefuroxime axetil which may be produced by the process of this invention is a novel form of matter and constitutes a further aspect of this invention.
A sample of this material has the IR spectrum in Nujol shown in the accompanying drawing.
The invention will now be illustrated by the following non-limiting Preparation and Examples.
The individual R and S isomers of eefuroxime 1-acetoxyethyl ester are denoted for convenience by -the letters A and B, these letters being used to denote the respective isomers as in British Patent No. 1571683. The identities of isomers A and B have not been assigned. The isomer ratios given in the following Examples are expressed as A:B. All temperatures are given In °C.
Preparation 1 Sodium Cefuroxime Chlorosulphonyl isocyanate (226 ml) was added to a solution of triethylamine (10 ml) in methyl acetate (3.8 1). The resulting clear solution was cooled to 15° and a suspension of (6R,7R)3-hydroxymethyl-7-[2-2-(fur-2-yl)-2-methoxyiminoacetamido]ceph"3-em-4-carboxylic acid (763g) in methyl acetate (2.3 1), pre-cooled to -15°, was added over 10 minutes. The residual solid was rinsed in with methyl acetate (700 ml). The mixture was stirred at -5° for 30 minutes, a clear solution being obtained after 10 minutes. Water (1.2 1) IE! at 18° was added rapidly to the reaction mixture, the temperature rising quickly to 10° and then slowly to 17°. The mixture was stirred for 60 minutes at 15° to give a thick, white suspension.
Methyl acetate (3.6 1) was added followed by a steady addition of a solution of sodium hydroxide (288 g) in water (5.2 1). This gave a clear twophase mixture at 26° with a pH of 2.35. The layers were separated and the upper, organic layer was washed with a solution of sodium chloride (600 g) in water (2 1). The two aqueous layers were washed sequentially with methyl acetate- (2 1) .
The organic layers were bulked, stirred with Nor it SX Plus charcoal (76 g) for 30 minutes and filtered through a bed of Hyflo Supercel, the bed being washed with methyl acetate (1.5 1). The filtrate and wash were combined and stirred at 20° whilst a solution of sodium 2-ethyIhexanoate (338 g) in a mixture of methyl acetate (2 I) and water (40 ml) was added over 20 minutes to give a white suspension with a pH of 5,5. The suspension was stirred for minutes and filtered, and the cake was washed with methyl acetate (5 χ 1 1), sucked dry, and dried at 30° in vacuo for 24 hours to give sodium on (c0.5; 0.1M pH [U+ 60° cefuroxime (851.9 g) 4.5 buffer); Xmax ™ 387); impurities by HPLC 2.0%. Assay (HPLC) 92% m/m; Water content (Karl Fisher) 2.8% m/m; Solvents (g.l.c.) 0.5% m/m.
Example 1 Cefuroxime Axetil (RS)-1-Acetoxyethylbromide (12-5 g) was added to a stirred mixture of sodium cefuroxime (20 g) (prepared by a method similar to that in Preparation 1) in dimethyl acetamide (110 ml) at 0°C- The mixture was stirred at +1° for 90 minutes and potassium carbonate (0.5 g) was added. Stirring was continued for a further 2 hours at 1-3° when the reaction mixture was added to a rapidly stirred mixture of ethyl acetate (200 ml) and aqueous 3% sodium bicarbonate (200 ml) to destroy any excess 1-acetoxyethylbromide. After 1 hour the organic layer (1.5% Δ isomer by HPLC) was separated, washed with M hydrochloric acid (100 ml) and aqueous 20% sodium chloride containing 2% sodium bicarbonate (30 ml). All three aqueous phases were sequentially washed with ethyl acetate (100 ml). The combined organic extracts were stirred for 30 minutes with charcoal (Nor it SX Plus; 2g), filtered through a kieselgfihr bed which was washed with ethyl acetate (2 x 25 ml); The combined filtrate and washes were evaporated in vacuo to 150 g and stirred at ambient temperature for 1 hour until the crystallisation was well established. Di-isopropyl ether (250 sal) was added over 45 minutes to complete the crystallisation and stirring was continued for an additional 1 hour. The product was collected by filtration, washed with 2:1 di-isopropyl ether/ethyl acetate (150 ml) and dried for a weekend in vacuo at 50° to give crystalline cefuroxime axetil (19.3 g) with an infra-red spectrum in Nujol as shown in the Figure in the accompanying drawing which is typical of a mixture of crystalline isomers.
Solvent content (GLC) 0.2% m/m. Impurities by KPLC 1.8% including A isomer 0.3% m/m; E-isomer 0.6% m/m. Isomer ratio (HPLC) 1.09:1 [οΠθ (1% in dioxan) +37°; E^m (278 mm, MeOH) 389. Assay by HPLC 99% m/m (uncorrected).
Example 2 Cefuroxime Axetil A stirred suspension of sodium cefuroxime (20 g) in dimethylacetamide (110 ml) was cooled to 15° and (RS)-1-acetoxyethyl bromide (12.5 g) was added.
Stirring at the foregoing temperature was continued for 45 minutes and potassium carbonate (0.5 g) was added. After stirring the mixture for an additional minutes at 15° it was poured into a rapidly stirred mixture of ethyl acetate (200 ml) and aqueous 3% sodium bicarbonate (200 ml). After 1 hour the layers were separated and the organic phase (HPLC showed 1.6% Δ isomer) was washed with M hydrochloric acid (100 ml) and aqueous 20% sodium chloride containing 2% sodium bicarbonate (30 ml). All the aqueous phases were sequentially washed with ethyl acetate (100 ml). The combined organic extracts were stirred for 30 minutes with charcoal (Nor it SX Plus; 2 g) ,, filtered through a bed of kiesielgQhr which was washed with ethyl acetate (2 x 25 ml). After evaporating the combined filtrate and washes to 120 g the concentrate was stirred for 20 minutes to enable crytallisation to become established. Industrial methylated spirit (120 ml) was added rapidly followed over 15 minutes by distilled water (240 ml). The resultant slurry was concentrated in vacuo to 310 g and stirred at ambient temperature for 45 minutes. The product was harvested, washed with distilled water (200 ml) and dried for 67 hours in vacuo at 50° to give crystalline cefuroxime axetil. (20.01 g). Solvent content (GLC) » 2 0.2% xn/m; impurities (HPLC) 1.5% m/m including isomer 0.5% m/m and E-isomer 0.6% m/m; isomer ratio i $ 1.01:1; (a)_(l% in dioxan) +40°; E, (278 nm, methanol) U XCul 388; Assay by HPLC 98% m/m (uncorrected).
Example 3 Cefuroxime Axetil Sodium cefuroxime (20 g) was stirred with dimethylacetamide (100 ml) at ca 25° for 15 minutes, the mixture was cooled to 15° and (RS)-1-acetoxyethyl bromide (9.8 ml) was added. The mixture was stirred for a further 90 minutes at 14-16°, adding 60-mesh potassium carbonate (0.5 g) halfway through this period. The red-brown mixture was then diluted with ethyl acetate (200 ml) and 3% aqueous sodium hydrogen carbonate (200 ml) and stirred for an hour at ambient temperature (ca 25°). The layers were then separated and the aqueous layer was re-extracted with ethyl acetate (200 ml) and discarded (a, 0,21°/dm). The organic solutions were washed sequentially with M hydrochloric acid (100 ml), then 20% sodium chloride (30 ml) containing 2% sodium hydrogen carbonate and were then combined and treated with Nor it SX Plus charcoal (2 g) for 25 minutes. The charcoal was filtered off through a Standard Supercel pad, the filter was washed with ethyl acetate (50 ml), and the combined filtrates were evaporated in vacuo to 120 g. The residual solution was seeded, stirred at 22° for 1 hour when toluene (250 ml was run into the stirred slurry over 30 minutes, and the mixture stirred for a further 30 minutes. The suspension was then re-evaporated in vacuo to 182 g, cooled to ca 25° and stirred for 30 minutes. The product was harvested, washed with toluene (100 ml), suctiondried for 15 minutes, then dried in vacuo at 45° overnight to give crystalline cefuroxime axetil (19.8 g) Solvents by GLC, 0.9% (StAc 0.7%; toluene 0.15%); impurities by HPLC, 0.9%, HPLC assay 100%, isomer ratio 1.03:1, Δ2< 0.1% m/m. Water (by Karl Fischer) 0.4% m/m.
Example 4 Cefuroxime A>xetil The washed and evaporated (ca 125 g) ethyl acetate solution of cefuroxime axetil obtained from a similar reaction to that described in Example 1 was stirred at ambient temperature until crystallisation was well established. Light petroleum ether (b.p. 100120°; 188 ml) was added dropwise during 1 hour after which the suspension was stirred at ambient temperature for a further 2 hours. The crystalline precipitate was collected by filtration, displacement washed with 2:1 light petroleum ether (b.p. 100-120°) ethyl acetate mixture (75 ml) and dried overnight at 40° in vacuo to give the title compound, (19.2 g) . Water (Karl Fischer) 0.4% m/m, solvents (glc) 0.4% m/m.
Impurities by HPLC 1.1% m/m A2 Assay by HPLC 100% m/m. (of which 0.1% and 0.6% m/m were and anti isomer respectively); the isomer ratio was 0.98:1.
Example 5 Cefuroxime Axetil· A washed and concentrated (ca 125 g) solution of the required cefuroxime acetil in ethyl acetate as prepared in Example 1 was stirred for 1 hour at 33° until crystallisation was well established.
After storing the suspension overnight at ambient temperature IMS (62.5 ml) was added over 5 minutes with stirring followed, over the next 1 hour by light petroleum ether (b.p. 100-120°; 250 ml). After stirring the crystalline suspension for a further 1.5 hours it was harvested, displacement washed with 2:1 light petroleum ether (b.p. 100-120° - ethyl acetate mixture (75 ml) and dried overnight in vacuo at 45° to give the title compound, 19.2 g. Water (Karl Fischer) 0.2% m/m; solvents (glc) 0.8% m/m. Impurities by HPLC 0.8% m/m (of which 0.1% m/m and 0.7% m/m were -9 fl" and anti isomers respectively); isomer ratio was 1.05:1. Assay by HPLC 96% m/m.
Example 6 Cefuroxime Axetil A washed and charcoaled concentrate (ca 100 g) of cefuroxime axetil in ethyl acetate, containing ca 2% A isomer, obtained similarly to that in Example 1 was seeded and stirred for 30 minutes until crystallisation was well established. Isopropanol (100 ml) was added dropwise over 30 minutes followed over 50 minutes by distilled water (170 ml). The resultant slurry was concentrated in vacuo to 250 g and cooled to 12° over a period of 1 hour. The crystalline product was collected by filtration, displacement washed with an ice-cold solution of 20% isopropanol in distilled water (100 ml) and dried for a weekf end in vacuo at 40° „ The title compound amounted to 20.1 g. Water (Karl Fischer) 0.4% m/m, solvents * (glc) 0.03% m/m- Impurities by HPLC 1.5% (of which 0.4% m/m and ca 0.6% m/m were Δ and anti isomers respectively); isomer ratio 1.05:1.
Claims (10)
1. A process for the preparation of highly pure crystalline cefuroxime 1-acetoxyethyl ester which comprises crystallising cefuroxime 1-acetoxyethylester from a solution thereof in an organic or aqueous solvent or a mixture thereof, isolating and drying the product.
2. A process as claimed cefuroxime 1-acetoxyethyl ratio of R to S isomer of
3. A process as claimed the solvent includes a es
4. A process as claimed solvent comprises an este optionally in admixture w or aromatic hydrocarbon; ' admixture with water.
5. A process as claimed the solvent comprises an water. in claim 1 wherein the ester crystallises in a approximately 1:1. in claim 1 or claim 2 wherein er. in claim 3 wherein the or halogenated hydrocarbon th an ether, or an aliphatic τ a ketone or amide in in claim 1 or claim 2 wherein Icohol in admixture with
6. A process as claimed in claim 4 wherein the solvent is selected from methyl or ethyl acetate, optionally in admixture with diisopropyl ether, petroleum ether or toluene.
7. A process as claimed in any of the preceding claims wherein at least a later portion of the crystallisation step is carried out at from 10 to 30°C.
8. A process substantially as hereinbefore described with reference to the Examples.
9. Crystalline cefuroxime 1-acetoxyethyl ester having a purity level of at least 95% mass/mass.
10. Crystalline cefuroxime 1-acetoxythyl ester having the IR spectrum as shown in the accompanying drawing .
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB838320521A GB8320521D0 (en) | 1983-07-29 | 1983-07-29 | Chemical process |
Publications (2)
Publication Number | Publication Date |
---|---|
IE841938L IE841938L (en) | 1985-01-29 |
IE57726B1 true IE57726B1 (en) | 1993-03-24 |
Family
ID=10546505
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IE1938/84A IE57726B1 (en) | 1983-07-29 | 1984-07-27 | Improvements in or relating to cephalosporins |
Country Status (21)
Country | Link |
---|---|
JP (1) | JPH0613526B2 (en) |
KR (1) | KR910008377B1 (en) |
AT (1) | AT392470B (en) |
AU (2) | AU582121B2 (en) |
BE (1) | BE900241A (en) |
CA (1) | CA1265511A (en) |
CH (1) | CH662121A5 (en) |
DE (1) | DE3427828A1 (en) |
DK (1) | DK165505C (en) |
ES (1) | ES534695A0 (en) |
FI (1) | FI76808C (en) |
FR (1) | FR2549837B1 (en) |
GB (2) | GB8320521D0 (en) |
IE (1) | IE57726B1 (en) |
IL (1) | IL72536A (en) |
NL (1) | NL8402372A (en) |
NO (1) | NO167292C (en) |
NZ (1) | NZ209046A (en) |
PT (1) | PT78985B (en) |
SE (1) | SE463263B (en) |
ZA (1) | ZA845830B (en) |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB8400024D0 (en) * | 1984-01-03 | 1984-02-08 | Glaxo Group Ltd | Cephalosporin antibiotics |
GB8524001D0 (en) * | 1985-09-30 | 1985-11-06 | Glaxo Group Ltd | Pharmaceutical composition |
US5063224A (en) * | 1990-07-09 | 1991-11-05 | Eli Lilly And Company | R-cefuroxime axetil |
IT1277426B1 (en) * | 1995-08-03 | 1997-11-10 | Acs Dobfar Spa | BIOAVAILABLE CRYSTALLINE FORM OF CEFUROXIMA AXETIL |
CN1111537C (en) * | 1997-05-15 | 2003-06-18 | 第一制糖株式会社 | The preparation method of highly pure crystalline form of cefuroxime axetil |
KR100228264B1 (en) * | 1997-08-02 | 1999-11-01 | 김선진 | The synthetic method of crystalline cefuroxime axetil |
CA2209868C (en) * | 1997-08-15 | 2001-08-14 | Bernard Charles Sherman | Pharmaceutical compositions comprising cefuroxime axetil |
IN186539B (en) * | 1997-09-29 | 2001-09-29 | Ranbaxy Lab Ltd | |
ATE212638T1 (en) * | 1998-02-20 | 2002-02-15 | Fako Ilaclari A S | METHOD FOR PRODUCING SOLUBLE CRYSTALLINE CEFUROXIM AXETIL |
IN190849B (en) | 2000-07-17 | 2003-08-23 | Ranbaxy Lab Ltd | |
AT411996B (en) | 2000-09-11 | 2004-08-26 | Sandoz Ag | METHOD FOR PRODUCING CEFUROXIME IN THE FORM OF ITS N-BUTYL LAMONIUM SALTS |
ITMI20011763A1 (en) * | 2001-08-10 | 2003-02-10 | Antibioticos Spa | HIGH-PURITY CEFUROXIME AXELITE PREPARATION PROCESS |
ITMI20011925A1 (en) * | 2001-09-14 | 2003-03-14 | Antibioticos Spa | METHOD APPLICABLE ON INDUSTRIAL SCALE FOR THE PREPARATION OF CEFUROXIME AXETILE CRISTALLINO |
TWI328006B (en) * | 2003-12-26 | 2010-08-01 | Nissan Chemical Ind Ltd | Crystal form of quinoline compound and process for its production |
CN100448879C (en) * | 2004-07-22 | 2009-01-07 | 北京化工大学 | Method for preparing unformed cefuroxime axetil |
DE102005019458A1 (en) | 2005-04-25 | 2006-10-26 | Grünenthal GmbH | Composition, useful in the preparation of pellets and the multi-particular-presentation form, comprises cefuroximaxetil and carrageenan of the group of lambda carrageenan, tau carrageenan and kappa carrageenan |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1571683A (en) * | 1976-02-16 | 1980-07-16 | Glaxo Operations Ltd | Ester derivatives of cefuroxime |
CA1094545A (en) * | 1976-02-16 | 1981-01-27 | Michael Gregson | Cephalosporin antibiotics |
GB1598568A (en) * | 1977-04-19 | 1981-09-23 | Glaxo Lab Ltd | Esters of(6r,7r)-3-carbamoyloxymethyl-7-((z)-2-(fur-2-yl)-2-methoxyiminoacetamido)-ceph-3-em-4-carboxylic acid |
JPS577485A (en) * | 1980-06-13 | 1982-01-14 | Takeda Chem Ind Ltd | Cephalosporin |
YU44680B (en) * | 1982-07-30 | 1990-12-31 | Glaxo Lab Ltd | Process for obtaining very pure amorphous form of cephuroxim axetile |
GB8400024D0 (en) * | 1984-01-03 | 1984-02-08 | Glaxo Group Ltd | Cephalosporin antibiotics |
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1983
- 1983-07-29 GB GB838320521A patent/GB8320521D0/en active Pending
-
1984
- 1984-07-27 IE IE1938/84A patent/IE57726B1/en not_active IP Right Cessation
- 1984-07-27 PT PT78985A patent/PT78985B/en unknown
- 1984-07-27 FI FI843011A patent/FI76808C/en not_active IP Right Cessation
- 1984-07-27 BE BE0/213398A patent/BE900241A/en not_active IP Right Cessation
- 1984-07-27 DE DE19843427828 patent/DE3427828A1/en not_active Ceased
- 1984-07-27 AT AT2444/84A patent/AT392470B/en not_active IP Right Cessation
- 1984-07-27 CA CA000459929A patent/CA1265511A/en not_active Expired - Fee Related
- 1984-07-27 NO NO843055A patent/NO167292C/en not_active IP Right Cessation
- 1984-07-27 DK DK366684A patent/DK165505C/en not_active IP Right Cessation
- 1984-07-27 JP JP59155694A patent/JPH0613526B2/en not_active Expired - Lifetime
- 1984-07-27 ES ES534695A patent/ES534695A0/en active Granted
- 1984-07-27 FR FR8412011A patent/FR2549837B1/en not_active Expired
- 1984-07-27 NL NL8402372A patent/NL8402372A/en not_active Application Discontinuation
- 1984-07-27 CH CH3672/84A patent/CH662121A5/en not_active IP Right Cessation
- 1984-07-27 SE SE8403897A patent/SE463263B/en not_active IP Right Cessation
- 1984-07-27 AU AU31256/84A patent/AU582121B2/en not_active Ceased
- 1984-07-27 ZA ZA845830A patent/ZA845830B/en unknown
- 1984-07-27 KR KR1019840004465A patent/KR910008377B1/en not_active IP Right Cessation
- 1984-07-27 GB GB08419202A patent/GB2145409B/en not_active Expired
- 1984-07-29 IL IL72536A patent/IL72536A/en not_active IP Right Cessation
- 1984-07-30 NZ NZ209046A patent/NZ209046A/en unknown
-
1989
- 1989-06-16 AU AU36601/89A patent/AU634965B2/en not_active Ceased
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Date | Code | Title | Description |
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MM4A | Patent lapsed |