STUDIES ON MICROBIAL DEGRADATION OF CEPHALOSPORIN C DERIVATIVES. II

Cephalosporin podand derivatives.

work in the synthesis of podand molecules6), the present paper describes the preparation of certain podand-type trimers of cephalosporin antibiotics (Scheme 1 ). As the central block of the target trimers the tricarboxylic acid 3 was employed, which was obtained by the alkylation of phloroglucinol (1) with methyl bromoacetate and subsequent alkaline hydrolysis. The tert-butyl esters of 7-aminoc...

Effect of methionine, norleucine, and lysine derivatives on cephalosporin C formation in chemically defined media.

Demain, A. L. (Merck Sharp & Dohme Research Laboratories, Rahway, N.J.), Joanne F. Newkirk, and D. Hendlin. Effect of methionine, norleucine, and lysine derivatives on cephalosporin C formation in chemically defined media. J. Bacteriol. 85: 339-344. 1963.-Chemically defined media were developed for production of cephalosporin C by Cephalosporium sp. In such media, the requirement for methionine...

Biosynthesis of cephalosporin C.

The superiority of d-methionine over l-methionine for stimulation of cephalosporin C synthesis in a crude medium was confirmed. The optimal level of dl-methionine was 0.5%. Methionine stimulates growth slightly but this is not thought to be the cause of the marked stimulation of antibiotic synthesis. Of a large number of sulfur compounds tested, only dl-methionine-dl-sulfoxide and S-methyl-l-cy...

Preparation of 7-epi-cephalosporin derivatives.

position 6,1-4) the preparation of 7-epi-aminocephalosporanic 'acid (7a-ACA) has thus far not been reported. Some 7-epi-cephalosporins have been prepared by base-catalyzed epimerization of cephalosporin sulfoxidesu or acidcatalyzed ring expansion of 6-epi-penicillins.e) Both procedures, however, are not convenient for the preparation of 7-epi-cephalosporin derivatives. We wish to report the direct

Applied and Mechanistic Studies of Microbial 17beta-estradiol Degradation