HETERO DRUGS LIMITED Patent applications |
Patent application number | Title | Published |
20130345418 | PROCESS FOR PURIFICATION OF APREPITANT - The present invention relates to a process for obtaining pure aprepitant substantially free of undesired diastereomeric isomer, namely 5-[2(S)-[1(RS)-[3,5-bis(trifluoromethyl)-phenypethoxy]-3-(S)-(4-fluorophenyl)-morpholin-4-yl-methyl]-3,4-dihydro-2H-1,2,4-triazol-3-one. The present invention further provides an improved process for preparation of aprepitant crystalline form II. The present invention also relates to novel amorphous form of aprepitant, a process for its preparation and to a pharmaceutical composition comprising it. The present invention further relates to aprepitant having a mean particle size of less than about 11.5 microns, a process for its preparation and to a pharmaceutical composition comprising it. Thus, for example, aprepitant having a content of diastereomeric impurity of 1.1% is dissolved in ethyl acetate at 70° C., the solution is concentrated to half the initial volume by distilling off ethyl acetate, and the resulting solid is collected at 0-5° C. to give pure aprepitant substantially free of its diastereomeric impurity. | 12-26-2013 |
20120271047 | Novel Polymorphs of Efavirenz - The present invention relates to novel amorphous and crystalline forms of efavirenz, processes for their preparation and pharmaceutical compositions containing them. In accordance with the present invention efavirenz crude is dissolved in acetone at 25° C.-30° C., the solution is slowly added to water for 30 minutes at 0° C.-5° C., stirred for 1 hour at the same temperature, the separated solid is filtered, washed with water and dried at 55° C.-60° C. for 5 hours to give amorphous efavirenz. | 10-25-2012 |
20120095054 | POLYMORPHS OF ESOMEPRAZOLE SALTS - The present invention relates to a high assayed esomeprazole magnesium dihydrate substantially free of its trihydrate form. The present invention further provides an improved and commercially viable process for preparation of high assayed esomeprazole magnesium dihydrate substantially free of its trihydrate form. The present invention also provides an improved process for preparation of pure amorphous esomeprazole magnesium. The present invention further provides an improved and commercially viable process for preparation of substantially enantiomerically pure esomeprazole in neutral form or as a pharmaceutically acceptable salt or as its solvates including hydrates. The present invention also provides solid form of esomeprazole calcium salt, its polymorphs (form 1, form 2 and amorphous form) and processes for their preparation thereof. | 04-19-2012 |
20120022256 | Novel Hydrated Form of Erlotinib Free Base and a Process For Preparation Of Erlotinib Hydrochloride Polymorph Form A Substantially Free of Polymorph Form B - The present invention provides a novel and stable hydrated form of erlotinib free base, and a process for its preparation thereof. The present invention also provides a process for preparation of erlotinib hydrochloride crystalline polymorph a substantially free of polymorph B. The present invention further relates to erlotinib hydrochloride crystalline particles having mean particle size (D | 01-26-2012 |
20110144149 | GEMIFLOXACIN PROCESS AND POLYMORPHS - The present invention provides a novel process for the preparation of gemifloxacin and its pharmaceutically acceptable acid addition salts in high yield. The present invention also relates to novel polymorphs of gemifloxacin free base and its hydrates to the processes for their preparation and to pharmaceutical compositions comprising them. The present invention also relates to infusion solutions of gemifloxacin and to processes for their preparation. Thus, 7-chloro-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro-1,8-naphth-yridine-3-carboxylic acid is reacted with a mixture of acetic anhydride, acetic acid and boric acid to give borane compound, which is then treated with 4-Aminomethyl-3-methoxyimino-pyrrolidinium dimethanesulfonate in presence of triethylamine, followed by treatment with 3.5% sodium hydroxide solution to give gemifloxacin free base. | 06-16-2011 |
20110136855 | GEMIFLOXACIN PROCESS AND POLYMORPHS - The present invention provides a novel process for the preparation of gemifloxacin and its pharmaceutically acceptable acid addition salts in high yield. The present invention also relates to novel polymorphs of gemifloxacin free base and its hydrates to the processes for their preparation and to pharmaceutical compositions comprising them. The present invention also relates to infusion solutions of gemifloxacin and to processes for their preparation. Thus, 7-chloro-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro-1,8-naphth-yridine-3-carboxylic acid is reacted with a mixture of acetic anhydride, acetic acid and boric acid to give borane compound, which is then treated with 4-Aminomethyl-3-methoxyimino-pyrrolidinium dimethanesulfonate in presence of triethylamine, followed by treatment with 3.5% sodium hydroxide solution to give gemifloxacin free base. | 06-09-2011 |
20100234614 | PROCESS FOR PURE IRBESARTAN - The present invention provides an improved and commercially viable process for preparation of irbesartan intermediate, 1-[(2′-cyanobiphenyl-4-yl)methyl]-2-n-butyl-4-spirocyclopentane-2-imidazolin-5-one, substantially free of 1-[(2′-cyanobiphenyl-4-yl)methyl]-2-n-propyl-4-spirocyclopentane-2-imidazolin-5-one impurity, thereby producing irbesartan substantially free of the undesired propyl analog impurity, namely 2-propyl-3-[[2′-(1H-tetrazol-5-yl)[1,1′-biphenyl]-4-yl]methyl]-1,3 -diazaspiro[4.4]non-1-en-4-one. The present invention also provides a process for preparation of irbesartan substantially free of tin content. The present invention further provides a commercially viable process for preparation of irbesartan in high purity and in high yield. | 09-16-2010 |
20100227890 | POLYMORPHS OF ESOMEPRAZOLE SALTS - The present invention relates to a high assayed esomeprazole magnesium dihydrate substantially free of its trihydrate form. The present invention further provides an improved and commercially viable process for preparation of high assayed esomeprazole magnesium dihydrate substantially free of its trihydrate form. The present invention also provides an improved process for preparation of pure amorphous esomeprazole magnesium. The present invention further provides an improved and commercially viable process for preparation of substantially enantiomerically pure esomeprazole in neutral form or as a pharmaceutically acceptable salt or as its solvates including hydrates. The present invention also provides solid form of esomeprazole calcium salt, its polymorphs (form 1, form 2 and amorphous form) and processes for their preparation thereof. | 09-09-2010 |
20100204478 | IMPROVED PROCESS FOR AMOPHOUS RABEPRAZOLE SODIUM - The present invention provides an improved and efficient process for the preparation of highly pure amorphous rabeprazole sodium. Thus, for example, rabeprazole is dissolved in an alcoholic sodium hydroxide solution followed by carbon treatment, the resulting filtrate is distilled under vacuum at 50-52° C. followed by co-distillation with cyclohexane and the resulting residue is dissolved in anisole; the solution is added to cyclohexane under agitation and then the precipitated solid collected by filtration or centrifugation. | 08-12-2010 |
20100197910 | PROCESS FOR PREPARATION OF PRULIFLOXACIN USING NOVEL INTERMEDIATES - The present invention provides a novel process for the preparation of the prulifloxacin intermediate, 6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3] thiazeto[3,2-a]quinoline-3-carboxylic acid, thereby producing prulifloxacin and its pharmaceutical acceptable acid addition salts thereof in high purity and in high yield using novel intermediates in lesser reaction time. Thus, for example, ethyl 6,7-difluoro-1-methyl-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylate is reacted with boric acid in the presence of acetic anhydride and acetic acid to give a borane compound, which is then condensed with piperazine in the presence of acetonitrile and dimethylsulfoxide, followed by treatment with potassium hydroxide solution to give 6-fluoro-1-methyl-4-oxo-7-(1-piperazinyl)-4H-[1,3] thiazeto [3,2-a]quinoline-3-carboxylic acid. | 08-05-2010 |
20100174087 | PROCESS FOR PREPARATION OF ENANTIOMERICALLY PURE ESOMEPRAZOLE - The present invention provides an improved and commercially viable process for preparation of substantially enantiomerically pure esomeprazole in neutral form or as a pharmaceutically acceptable salt or as its solvates including hydrates. Thus, for example, a compound containing a mixture of 1-(S)-camphorsulfonyl-5-methoxy-2-[(3,5-dimethyl-4-methoxy-2-pyridyl)methyl-(S)-sulfinyl]-1H-benzimidazole and 1-(S)-camphorsulfonyl-6-methoxy-2-[(3,5-dimethyl-4-methoxy-2-pyridyl)methyl-(S)-sulfinyl]-1H-benzimidazole is hydrolyzed with barium hydroxide, isolated the resulting esomeprazole barium salt followed by neutralization with an acid to yield substantially enantiomerically pure esomeprazole in neutral form and then converted into its pharmaceutically acceptable salts. | 07-08-2010 |
20100166850 | EPROSARTAN MESYLATE CRYSTALLINE PARTICLES AND A PROCESS FOR PREPARING PURE EPROSARTAN - The present invention relates to eprosartan mesylate particles having relatively larger surface area, to the methods for the manufacture of said crystalline particles, and to pharmaceutical compositions comprising said crystalline particles. The present invention further relates to crystalline solid of eprosartan acetate, to a process for its preparation and to a pharmaceutical composition comprising it. The present invention also provides substantially pure eprosartan free base and process for its preparation. | 07-01-2010 |
20100152302 | NOVEL CRYSTALLINE FORMS OF ATOVAQUONE - The present invention relates to two novel and stable crystalline forms of atovaquone, to processes for their preparation and to pharmaceutical compositions comprising them. The present invention also provides crystalline particles of atovaquone having a specific surface area of from about 0.7 m | 06-17-2010 |
20100137613 | PROCESS FOR EPROSARTAN - The present invention provides an improved and commercially viable process for preparation of eprosartan and its pharmaceutically acceptable acid addition salts thereof in high purity and in high yield. Thus, for example, methyl 4-[[2-butyl-5-formyl-1 H-imidazol-1-yl]methyl]benzoate is reacted with ethyl 2-carboxy-3-(2-thienyl)propionate in the presence of a base, such as piperidine or piperidinium propionate in propionic acid, in cyclohexane solvent to give ethyl (αE)-α-[(2-n-butyl-1-[(4-(methoxy-carbonyl) phenyl]methyl]-1 H-imidazol-5-yl]methylene-2-thiophene propionate substantially free of decarboxylate impurity namely, ethyl 3-(2-thienyl)propionate, which is then subjected to base hydrolysis followed by treatment with methanesulfonic acid to obtain eprosartan mesylate in high purity and in high yield. | 06-03-2010 |
20100136116 | NOVEL HYDRATED FORM OF ERLOTINIB FREE BASE AND A PROCESS FOR PREPARATION OF ERLOTINIB HYDROCHLORIDE POLYMORPH FORM A SUBSTANTIALLY FREE OF POLYMORPH FORM B - The present invention provides a novel and stable hydrated form of erlotinib free base, and a process for its preparation thereof. The present invention also provides a process for preparation of erlotinib hydrochloride crystalline polymorph A substantially free of polymorph B. The present invention further relates to erlotinib hydrochloride crystalline particles having mean particle size (D | 06-03-2010 |
20100130741 | PROCESS FOR ERLOTINIB HYDROCHLORIDE - The present invention provides an improved and commercially viable process for preparation of erlotinib substantially free of N-methoxyethyl impurity, namely N-[(3-ethynylphenyl)-(2-methoxyethyl)]-6,7-bis(2-methoxyethoxy)-4-quinazolinamine, and its pharmaceutically acceptable acid addition salts thereof in High purity and in high yield. According to the present invention, erlotinib or a pharmaceutically acceptable acid addition salt of erlotinib substantially free of N-methoxyethyl impurity is prepared by isolating erlotinib or a pharmaceutically acceptable salt of erlotinib from a solvent medium comprising dimethyl sulfoxide and an alcoholic solvent. | 05-27-2010 |
20100093804 | NOVEL CRYSTALLINE FORM OF LANSOPRAZOLE - The present invention relates to a novel and stable crystalline polymorph of lansoprazole, a process for its preparation and to a pharmaceutical composition comprising it. Thus, for example, lansoprazole crude is dissolved in methanol at 20-30° C. followed by stirring and the solution is cooled to 0-10° C. The resulting solution is stirred for 1 hour to 1 hour 30 minutes at 0-10° C., the solid is filtered and then dried to give lansoprazole crystalline form III. | 04-15-2010 |
20100087653 | NOVEL PROCESS FOR THE PREPARATION OF LERCANIDIPINE - The invention provides a novel process for the preparation of lercanidipine or a pharmaceutical acceptable salt using novel intermediates. Thus, 2,N-dimethyl-N-(3,3-diphenylpropy1)-1-amino-2-propanol is reacted with trimethylsilyl chloride in presence of triethyl amine in methylene chloride to give 2,N-dimethyl-2-(trimethylsilyloxy)-N-(3,3-diphenylpropy1)-1-propanamine, which is then reacted with 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carbonyl chloride for 2 hours and crystallized to obtain lercanidipine hydrochloride. | 04-08-2010 |
20100076197 | PROCESS FOR RIMONABANT - The present invention provides an improved and commercially viable process for the preparation of rimonabant substantially free of amide impurity, namely 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl-4-methyl-pyrazole-3-carboxamide and its pharmaceutically acceptable acid addition salts thereof. Thus, for example, 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl-4-methyl-pyrazole-3-carboxylic acid chloride is reacted with 1-aminopiperidine in the presence of a base and optionally a phase transfer catalyst is used such as tetra-butylammonium bromide in a biphasic reaction medium containing water and a water-immiscible solvent to obtain pure rimonabant. | 03-25-2010 |
20100076022 | NOVEL POLYMORPHS OF RIMONABANT - The present invention discloses novel and stable polymorphs of rimonabant, its hydrates and solvates, to the processes for their preparation and to pharmaceutical compositions comprising them. The present invention further discloses a novel and stable amorphous form of rimonabant, process for its preparation and a pharmaceutical composition comprising it. The present invention also provides an improved process for the preparation of rimonabant crystalline Form II. Thus, for example, rimonabant is dissolved in methylene dichloride, stirred for 10 minutes at 25-30° C. and then the solvent distilled off under vacuum at 40° C. The resulting residue is stirred with water and the separated solid is collected at 25-30° C. to give a stable crystalline rimonabant hydrate. | 03-25-2010 |
20090275746 | SOLID FAROPENEM FREE ACID - The present invention provides solid form of faropenem free acid, its hydrates and processes for their preparation thereof. Thus, for example, dissolving an alkali metal salt of faropenem in water, adjusting the pH of the solution formed with an acid to below about 2.5 and collecting the precipitated solid to obtain solid faropenem free acid. | 11-05-2009 |
20090198066 | AMORPHOUS ESOMEPRAZOLE HYDRATE - The present invention relates to a novel amorphous form of esomeprazole hydrate, to a process for its preparation and to a pharmaceutical composition containing it. Thus, tetrahydrofuran and water are added to esomeprazole potassium salt at 25-30° C., cooled to 20° C. and then the pH is adjusted to 7.5-8.0 with acetic acid. The reaction mass is cooled to 5° C., stirred for 2 to 3 hours at 0-5° C., filtered the mass, washed with chilled mixture of water and tetrahydrofuran (2:1) and again washed with water. The wet cake is dried at 30-35° C. under vacuum to reach the moisture content to 25-30%. The solid is again dried in rotovapour at 25-30° C. under nitrogen atmosphere to give amorphous esomeprazole hydrate. | 08-06-2009 |
20090197907 | NOVEL CRYSTALLINE FORM OF RUPATADINE FREE BASE - The present invention relates to a novel crystalline form of rupatadine free base, process for its preparation and to a pharmaceutical composition containing it. In accordance with the present invention rupatadine is suspended in n-hexane, n-heptane, cyclohexane, diethyl ether or diisopropyl ether, stirred for at least 1 hour, filtered the solid and dried to give crystalline rupatadine form-B. The isolation of novel rupatadine free base as crystalline form-B may be useful as a purification of rupatadine or a salt thereof. | 08-06-2009 |
20090177010 | PROCESS OF MAKING SERTRALINE FORM I - The present invention discloses novel and improved processes for preparation of sertraline hydrochloride crystalline form II. Thus, for example, sertraline free base is dissolved in isoamyl alcohol at 25-30° C., pH of the mass is adjusted to 2.0 with conc. hydrochloric acid (36%) at 25-30° C. and then stirred for 14 hours at 25-30° C. Filtered the solid and dried at 65° C. for 4 hours to give sertraline hydrochloride crystalline form II. The present invention also provides a novel process for preparation of sertraline hydrochloride crystalline form I. | 07-09-2009 |
20090177009 | PROCESS OF MAKING SERTRALINE FORM II - The present invention discloses novel and improved processes for preparation of sertraline hydrochloride crystalline form II. Thus, for example, sertraline free base is dissolved in isoamyl alcohol at 25-30° C., pH of the mass is adjusted to 2.0 with conc. hydrochloric acid (36%) at 25-30° C. and then stirred for 14 hours at 25-30° C. Filtered the solid and dried at 65° C. for 4 hours to give sertraline hydrochloride crystalline form II. The present invention also provides a novel process for preparation of sertraline hydrochloride crystalline form I. | 07-09-2009 |
20090163513 | PROCESS FOR ZIPRASIDONE USING NOVEL INTERMEDIATES - The present invention relates to a novel process for the preparation of high purity ziprasidone and pharmaceutically acceptable acid addition salts of ziprasidone; and solvates and hydrates thereof using novel intermediates and a purification method for ziprasidone and pharmaceutically acceptable acid addition salts of ziprasidone; and solvates and hydrates thereof. | 06-25-2009 |
20090149670 | PROCESS FOR OBTAINING PURE OSELTAMIVIR - The present invention provides a process for obtaining highly pure crystalline form of oseltamivir free base, thus, for example, suspending or dissolving impure or non-crystalline oseltamivir free base in a hydrocarbon solvent and then isolating crystals to obtain oseltamivir free base in well defined crystalline form. The present invention also provides a process for preparation of oseltamivir phosphate in high purity. | 06-11-2009 |
20090149462 | PROCESS FOR PURIFICATION OF APREPITANT - The present invention relates to a process for obtaining pure aprepitant substantially free of undesired diastereomeric isomer, namely 5-[2(S)-[1(RS)-[3,5-bis(trifluoromethyl)-phenyl)ethoxy]-3-(S)-(4-fluorophenyl)-morpholin-4-yl-methyl]-3,4-dihydro-2H-1,2,4-triazol-3-one. The present invention further provides an improved process for preparation of aprepitant crystalline form II. The present invention also relates to novel amorphous form of aprepitant, a process for its preparation and to a pharmaceutical composition comprising it. The present invention further relates to aprepitant having a mean particle size of less than about 11.5 microns, a process for its preparation and to a pharmaceutical composition comprising it. Thus, for example, aprepitant having a content of diastereomeric impurity of 1.1% is dissolved in ethyl acetate at 70° C., the solution is concentrated to half the initial volume by distilling off ethyl acetate, and the resulting solid is collected at 0-5° C. to give pure aprepitant substantially free of its diastereomeric impurity. | 06-11-2009 |
20090082572 | PROCESS FOR AMORPHOUS ESOMEPRAZOLE - The present invention relates to a commercially viable process for preparation of amorphous esomeprazole. Thus, amorphous esomeprazole is prepared by suspending esomeprazole in water and then subjecting the suspension to lyophilization at −70° C. | 03-26-2009 |
20090076288 | PROCESS FOR ISOLATION OF DESIRED ISOMERS OF NEBIVOLOL INTERMEDIATES - The present invention relates to a simple and commercially viable process for separation of desired isomers of nebivolol intermediates from a mixture containing undesired isomers of nebivolol intermediates. Thus, (+)-[2R*[1S*,5S*(S*)]]+[2R*[1S*,5R*(R*)]]-α,α′-[phenylmethyliminobis(methylene)]bis[6-fluoro-3,4-dihydro-2H-1-benzopyran-2-methanol] is dissolved in diisopropyl ether at reflux temperature and cooled to below about 30° C. to obtain the desired (+)-[2R*[1S*,5S*(S*)]]-α,α′-[phenylmethyliminobis(methylene)]bis[6-fluoro-3,4-dihydro-2H-1-benzopyran-2-methanol]. | 03-19-2009 |
20090054682 | PROCESS FOR OSELTAMIVIR PHOSPHATE - The present invention provides an improved and commercially viable process for the preparation of oseltamivir phosphate. Thus, for example, ethyl (3R,4R,5S)-4-amino-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate is acetylated with acetic anhydride in methylene chloride in the presence of triethyl amine in the absence of water to give ethyl (3R,4R,5S)-4-(acetylamino)-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate. | 02-26-2009 |
20090012292 | NOVEL PROCESS FOR ACYCLIC PHOSPHONATE NUCLEOTIDE ANALOGS - The present invention provides a novel process for the preparation of acyclic phosphonate nucleotide analogs using novel intermediates. Thus, for example, (R)-9-(2-phosphonomethoxypropyl)adenine is reacted with dimethylformamide dimethylacetal to give N | 01-08-2009 |
20080293938 | Novel Process for the Preparation of Didanosine Using Novel Intermediates - present invention relates to novel crystalline alkali metal and alkaline earth metal salts of 2′,3′-dideoxy-2′,3′-didehydroinosine. The present invention also provides a novel process for preparation of didanosine in high yield and purity using novel intermediates. Thus, for example, 5′-O-acetyl-2′,3′-dideoxy-2′,3′-didehydroinosine is reacted with monomethyl amine to give 2′,3′-dideoxy-2′,3′-didehydro inosine, which is then reacted with sodium hydroxide and crystallized to give crystalline 2′,3′-dideoxy-2′,3′-didehydroinosine sodium salt. 2′,3′-Dideoxy-2′,3′-didehydroinosine sodium salt is hydrogenated using raney nickel catalyst in aqueous medium and then neutralized with hydrochloric acid to yield didanosine. | 11-27-2008 |
20080293773 | Amorphous Esomeprazole Hydrate - The present invention relates to a novel amorphous form of esomeprazole hydrate, to a process for its preparation and to a pharmaceutical composition containing it. Thus, tetrahydrofuran and water are added to esomeprazole potassium salt at 25-30 C, cooled to 20 C and then the pH is adjusted to 7.5-8.0 with acetic acid. The reaction mass is cooled to 5 C, stirred for 2 to 3 hours at 0-5 C, filtered the mass, washed with chilled mixture of water and tetrahydrofuran (2:1), and again washed with water. The wet cake is dried at 30-35 C under vacuum to reach the moisture content to 25-30%. The solid is again dried in rotovapour at 25-30 C under nitrogen atmosphere to give amorphous esomeprazole hydrate. | 11-27-2008 |
20080293760 | Gemifloxacin Process and Polymorphs - The present invention provides a novel process for the preparation of gemifloxacin and its pharmaceutically acceptable acid addition salts in high yield. The present invention also relates to novel polymorphs of gemifloxacin free base and its hydrates to the processes for their preparation and to pharmaceutical compositions comprising them. The present invention also relates to infusion solutions of gemifloxacin and to processes for their preparation. Thus, 7-chloro-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxylic acid is reacted with a mixture of acetic anhydride, acetic acid and boric acid to give borane compound, which is then treated with 4-Aminomethyl-3-methoxyimino-pyrrolidinium dimethanesulfonate in presence of triethylamine, followed by treatment with 3.5% sodium hydroxide solution to give gemifloxacin free base. | 11-27-2008 |
20080242858 | Process For the Preparation of Cefixime - There is provided an improved process for preparing cefixime. Thus, for example, 7-amino-3-vinyl-3-cephem-4-carboxylic acid is reacted with 2-mercapto-1,3-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-(methoxycarbonyl)-methoxyimino acetate in tetrahydrofuran and water at 4° C. in the presence of triethylamine. The reaction mass is extracted with ethyl acetate. 7-[2-(2-Amino-4-thiazolyl)-2-(methoxycarbonylmethoxyimino)acetamido]-3-vinyl-3-cephem-4-carboxylic acid triethylamine salt present in the aqueous layer is hydrolyzed with sodium hydroxide in less than 30 minutes and aqueous hydrochloric acid is added immediately to adjust the pH to 4.8 to 5.2. Then, aqueous hydrochloric acid is added at 35° C. to adjust the pH 2.5 and cooled to crystallize cefixime trihydrate in high purity. | 10-02-2008 |