摘要:
The preparation of a novel crystalline cefaclor and the conversion of such a product to cefaclor monohydrate are described. The new intermediate cefaclor is a particular crystalline form and possesses the same antibiotic properties as cefaclor monohydrate.
摘要:
The preparation of a novel crystalline cefaclor and the conversion of such a product to cefaclor monohydrate are described. The new intermediate cefaclor is a particular crystalline form and possesses the same antibiotic properties as cefaclor monohydrate.
摘要:
There is described the preparation of halogenated .beta.-lactam derivatives by introduction of a chlorine atom in the 3-position of the cephem nucleus starting from a 3-sulfonyloxycephem. Such starting materials are reacted with a chlorine ions donor in a basic medium.
摘要:
The present invention refers to process for the preparation of a tiazoline-azetidinone of formula I ##STR1## which comprises N-protecting in position 1 of (3S,4S)-3-phenylace tamido-4-acetoxy-azetidin-2-one, converting the product thus obtained into the corresponding thioamide and subsequently ciclyzing and deprotecting.
摘要:
A method for the removal of the formyl group from an ester of an N-formyl peptide or N-formyl aminoacid, in which the ester is reacted with urea in the presence of a polar solvent and a strong acid.
摘要:
Process for the preparation of polyhalogenated steroids, in particular of androstanic fluoro derivatives corticosteroids by means of the formation of new androstanic S-hydroxy alkyl or aralkyl-17-carbothioate intermediates.
摘要:
The process for the preparation of 6α-fluoro steroids, comprising the reaction of the corresponding 6β-fluoro steroids, or of 6α/6β isomeric mixtures with an organic base having a diazo iminic group, in a suitably selected organic solvent, is described.
摘要:
Described herein is a process for the preparation of 6&agr;-fluorosteroids of formula (I), in which R is chosen from H, OH and an alkyl group with from 1 to 4 carbon atoms and R′ is a carboxyalkyl group with from 1 to 4 carbon atoms in the alkyl chain, comprising the selective fluorination at the 6&agr;-position by treatment of the compound of formula (III), wherein R and R′ are as defined above, with an electrophilic fluorinating agent.
摘要:
Described herein is the isomerisation process of 6&bgr;-fluorosteroids into the corresponding pharmacologically active 6&agr;-fluoro derivatives, comprising the reaction of 6&bgr;-fluorosteroids, or 6&agr;/6&bgr; isomeric mixtures, with an organic base containing a diazoimino group in a suitable organic solvent.
摘要:
A process is disclosed for making 17-monoesters of 17 .alpha., 21-dihydroxy steroids by acylating a 17 .alpha., 21-dihydroxy steroid phosphate and then subjecting the intermediate 17-acyloxy-21-phosphate to dephosphorylation using an acid phosphatase to achieve enzymatic hydrolysis. Several new 17-monoesters having an anti-inflammatory property are also disclosed.