摘要:
A process for the preparation of cephalosporin antibiotic of the formula (I) which comprises: (i) activating the compound of formula (III) as acid halide in an organic solvent (ii) treating the reaction mass obtained from step (i) with water (iii) separating the organic layer containing the reactive derivative of formula (III) and condensing it with 7-amino cephalosporin derivative by maintaining the pH in the range 5.0-10.0 using an inorganic base of the formula (XV), and iv) cyclizing the compound of formula (XVI) with thiourea in the presence of solvent and salt of organic or inorganic acid at a temperature in the range of −50 to +50° C. to produce compound of formula (I).
摘要:
The present invention relates to a new stereoselective method for the preparation of tris-O-substituted-(E)-1-(3,5-dihydroxyphenyl)-2-(4-hydroxyphenyl)ethene derivative of the formula (I) which is a key intermediate in the synthesis of trans-resveratrol (I, R2=R2=R3=H). The invention also provides a method for the exclusive synthesis of trans-isomer of compounds of formula (I) without any contamination of cis-isomer.
摘要:
A process for the preparation of 3-methylcepham-4-carboxylate of the formula (I). wherein R2 and R3 may be same or different and represent hydrogen, halogen, amino, alkyl, phenacetamido, substituted acetamido, phthalimido with a proviso that both R2 and R3 are not NH2, phenacetamido, phthalimido and the like; R1 represents a lower alkyl, p-methoxybenzyl, p-nitrobenzyl, o-nitrobenzyl, o-methoxybenzyl, o-chlorobenzyl or diphenylmethyl group, or a suitable ester residue which can be deprotected at a latter stage, L represents a leaving group; which comprises cyclizing the compound of formula (III) using a cyclizing agent in the presence of organic or inorganic nitrites and a solvent at a temperature in the range of −40° C. to +60° C. to obtain compound of formula (I).
摘要:
An improved process for the purification of tazobactam or its derivatives of the formula (I) wherein R represents hydrogen, C1-C6alkyl, p-methoxybenzyl, o-nitrobenzyl, p-nitrobenzyl, o-chlorobenzyl, benzyl or diphenylmethyl, which comprises the steps of: i) slurrying the compound of formula (I) containing the impurity of the formula (V) using a solvent in the presence or absence of tartaric acid with or without the presence of water at 20-50° C. and ii) isolating the compound of formula (I) in pure form.
摘要:
This invention relates to an improved process for the industrial manufacture of S-adenosyl-L-methionine (SAMe) of formula (I), which consists of stereo-selective methylation of S-adenosyl-L-homocysteine (SAH) with the enrichment of active (S,S)-isomer.
摘要:
Compounds of general formula (II), wherein R1 represents R4 represents hydrogen or —CHO group, R5 represents hydrogen or trityl, R2 represents hydrogen or methoxy group, R3 represents —CH═CH2 or and M represents a dialkyl or dicycloalkyl ethylenediamine group selected from N,N′-diisobutylethylenediamine, N,N′-dicyclohexylethylenediamine, and N,N′-dicyclopentylethylenediamine, are useful in a process to make cephalosporin antibiotics of formula (I) wherein R represents hydrogen or pharmaceutically acceptable esters or alkali metals salts.
摘要:
This invention relates to an improved process for the industrial manufacture of S-adenosyl-L-methionine (SAMe) of formula (I), which consists of stereo-selective methylation of S-adenosyl-L-homocysteine (SAH) with the enrichment of active (S,S)-isomer.
摘要:
The present invention relates to novel polymorph of Ceftiofur sodium as a crystalline product. The present invention also provides a process for the preparation of crystalline Ceftiofur sodium of formula (I).
摘要:
The present invention relates to a process for the production of cephalosporin antibiotic intermediate of formula (I). More particularly relates to the preparation of the compound of formula (I) using a solvent medium selected from the group consisting of decalin (decahydronapthalene), hexane, cyclohexene, tetralin, petroleum ether, wherein X represents HI, HCI, H2SO4 and the like. The compound of formula (I) is an important intermediate in the preparation of Cefepime.
摘要翻译:本发明涉及制备式(I)的头孢菌素抗生素中间体的方法。 更具体地涉及使用选自十氢萘(十氢萘),己烷,环己烯,四氢化萘,石油醚,其中X代表HI,HCl,H 2 SO 4等的溶剂介质制备式(I)化合物。 式(I)化合物是头孢吡肟制剂中的重要中间体。
摘要:
The present invention relates to novel polymorph of Ceftiofur sodium as a crystalline product. The present invention also provides a process for the preparation of crystalline Ceftiofur sodium of formula (I).