摘要:
The present invention relates to preparation of Ceftiofur acid of formula (I), and its pharmaceutically acceptable salts. The process includes the steps of (i) condensing an activated derivative of wherein the activated derivative is selected from acid halides, mixed anhydrides and active amides, and wherein X represents halogen atom selected from chlorine and bromine, with silylated derivative of wherein R represents p-methoxybenzyl, p-nitrobenzyl or diphenylmethyl in the presence of a solvent at −40° C. to 0° C. to produce (ii) cyclising (V) with thiourea in the presence of water miscible solvent and sodium acetate at room temperature to produce cephalosporin (iii) deesterifying (VI) to produce (I) using anisole/trifluoroacetic acid, phenol/trifluoroacetic acid or formic acid at 0° C. to 10° C. and, if desired, (iv) converting (I), to its pharmaceutically acceptable salt. The invention also relates to intermediates (V) and (VI)
摘要:
The present invention relates to a method for the preparation of cephalosporin antibiotic of the formula (II), which comprises hydrolyzing and halogenating the ester of formula (III) by photochemical irradiation in one pot using a halogenating agent in the absence or presence of a solvent, to produce compound of formula (I), activating the 4-halogeno-2-substitutedimino-3-oxo-butyric acid of formula (I) using conventional activation agents gives compound of formula (IV), condensing the activated compound of the formula (IV) with 7-amino cephem derivative of the formula (V) to produce a compound of formula (VI), and cyclizing the compound of formula (VI) with thiourea to give cephalosporin compounds of the formula (II).
摘要:
An improved process is described for the purification of ropinirole hydrochloride. The process includes (i) dissolving ropinirole hydrochloride in water; (ii) treating the solution obtained in step (i) with sodium dithionate and charcoal; (iii) treating the filtrate obtained in step (ii) with water immiscible solvent and base and isolating the free base; and (iv) treating the free base obtained in step (iii) with ethanolic HCl to give ropinirole hydrochloride.
摘要:
A process for the preparation of Irbesartan of formula (I) using the step of, reacting biphenyl derivative of formula (VIa) wherein R represents a group selected from —CONH2 or compound of formula wherein X represents H or C1-4 alkyl, preferably methyl; or any other such group which can be converted to cyano group, with 1-veleramido cyclopentane carboxylic acid of formula (V) in the presence of an acid in an organic solvent to give biphenyl derivative of formula (VIIa) wherein R has the same meaning as mentioned hereinabove.
摘要:
An improved process for the preparation of ceftriaxone sodium comprising the steps of: i) reacting the 3-cephem derivative of formula (II) with halo acid derivative of formula (III) wherein X represents halogen and Y represent halogen in the presence of silylating agent and methylene chloride at −25 to 10° C., to produce (IV), ii) quenching the reaction by pouring the reaction mixture into water or in a aqueous solution of sodium carbonate, iii) preparing sodium salt solution of (IV) by adding sodium carbonate and separating the organic layer, iv) cyclizing the sodium salt of (IV) in the aqueous solution with thiourea at a temperature in the range of 0 to 30° C., v) adjusting the pH to 1.5 to 2.5 to precipitate the ceftriaxone free acid, vi) converting the ceftriaxone free acid to sodium salt using sodium-2-ethyl hexanoate in water and vii) precipitating and isolating the ceftriaxone sodium.
摘要:
The present invention relates to an improved process for the preparation of cefprozil DMF solvate of formula (I), which is useful for the preparation of cefprozil, comprising: i) reacting a compound of formula (VIII) with acetaldehyde to produce a compound of formula (IX), ii) deesterifying the carboxy protecting group of the compound of formula (IX) using an acid to yield a compound of formula (X), iii) converting the compound of formula (X) to a compound of formula (XI), iv) neutralizing the compound of formula (XI) followed by enzymatic hydrolysis to produce an APCA of formula (V), v) silylating the APCA using a mixture of trimethylsilylchloride and hexamethyldisilazane to produce silylated APCA of formula (XII), and vi) condensing the silylated APCA with a mixed anhydride to produce the DMF solvate compound of formula (I).
摘要:
The present invention provides new thioester derivatives of 4-halogeno-2-methoxyimino-3-oxo-butyric acid of the general formula (I), also, the invention provides a method by which the said thioester derivatives can be prepared by reacting 4-halogeno-2-methoxyimino-3-oxo-butyric acid of the general formula (II) with 2-mercapto-5-substituted-1,3,4-oxadiazoles of the general formula (III) in a solvent, in the presence of DMF/POCl3 and in presence of an organic base and if desired the so obtained thioester derivatives so obtained are reacted with 7-amino-cephem carboxylic acids of the general formula (V) to produce condensed products which are insitu reacted with thiourea to get cephalosporin antibiotic compounds having the general formula (VI).
摘要:
The present invention relates to an improved process for the preparation of 7-[4-[4-(2,3-dichlorophenyl)piperazin-1-yl]butoxy]-1,2,3,4-tetrahydroquinolin-2-one (Aripiprazole) having dimer impurity less than 0.15%, particularly, the present invention relates to an improved process for the preparation of 7-(4-chlorobutoxy)-3,4-dihydrocarbostyril of formula (I) having dimer impurity less than 0.5% which includes a step of reacting 7-hydroxy-tetrahydroquinolinone of formula (III) with 1-bromo-4-chlorobutane in the presence of a base in a solvent.
摘要:
The present invention relates to a process for the purification of Sucralose of formula (I) which comprises acetylation of substantially impure Sucralose to its penultimate intermediate 4,1′,6′-trichloro-4,1′,6′-trideoxy galactosucrose penta-acetate (TOPSA) of formula (VI) followed by purification of TOPSA and then deacetylation of purified TOPSA.
摘要:
A process for the preparation of Irbesartan of formula (I) using the steps of: (i) reacting 4′ aminomethyl-2-cyano biphenyl of formula (VI) with 1-veleramido cyclopentane carboxylic acid of formula (V) in an organic solvent and in the presence of an acid, without activating the —COOH group of compound of formula (V) to give 1-(2′cyanobiphenyl-4-yl-methylaminocarbonyl)-1-pentanoylamino cyclopentane of formula (VII). converting the compound of formula (VII) obtained in step (i) to Irbesartan of formula (I) by reacting the compound of the formula (VII) with tributyl tin azide in o-xylene to give Irbesartan of formula (I).