Preparation of .DELTA.3-7.ALPHA.-phenylacetamidodesacetoxycephalosporanic acid

Autor:	L. A. Kerremans, Hubert Vanderhaeghe, G. Decoster, P. G. Claes
Rok vydání:	1979
Předmět:	Pharmacology Trimethylsilyl Hydrobromide Ring (chemistry) Medicinal chemistry Cephalosporins Catalysis chemistry.chemical_compound chemistry Drug Discovery Side product Methods Organic chemistry Epimer Acetamide
Zdroj:	The Journal of Antibiotics. 32:820-827
ISSN:	1881-1469 0021-8820
Popis:	delta 3-7 alpha-Phenylacetamidodesacetoxycephalosporanic acid was prepared by ring expansion of 6-epi-benzylpenicillin-S-sulfoxide, using N,O-bis(trimethylsilyl)acetamide (BSA) as silylating and dehydrating agent and alpha-picoline/alpha-picoline hydrobromide as catalyst. In some experiments 7 alpha-phenylacetamido-3 beta-bromo-3 alpha-methylcepham-4 alpha-carboxylic acid was obtained as a side product. 7-Epimers in the desacetoxycephalosporanic series were also prepared by base-catalyzed epimerization of the benzyl 7 beta-(p-nitrobenzylideneimino)desacetoxycephalosporanate and of the S-sulfoxide of natural methyl 6-phenylacetamidodesacetoxycephalosporanate. In both reactions 1,5-diazabicyclo(4.3.0)non-5-ene (DBN) was used as epimerization catalyst.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b9a7ee208ee4648e163a9709c55feb57 https://doi.org/10.7164/antibiotics.32.820 Zobrazit plný text záznamu