FOERFARANDE FOER AVLAEGSNING AV SYRE FRAON 7 -ACYLAMINO-3-CEFEM-4-KARBOXYLSYRA-1-OXIDDERIVAT.

摘要

Multi-step one-pot process for the preparation of inter alia 7 beta -amino- and 7 beta -acylamino-3-substituted methyl-3-cephem-4-carboxylic acid derivatives starting from 7 beta -acylamino-3-methyl-3-cephem-4-carboxylic acid 1 beta -oxide derivatives, comprising a new process for deoxygenation of generally 7 beta -acylamino-3-cephem-4-carboxylic acid 1-oxide derivatives optionally substituted in the 7 alpha -position, which can be applied as single step or can be incorporated in multistep processes without isolation of intermediates. …The deoxygenation involves the use of phosphorus pentachloride and an olefine for removal of chlorine at least in part by addition to carbon-carbon double bond. …Preferred aspects are lasting protection of reactive substituents by silylation and preparation on industrial scale of generally 7 beta -amino-3-heterocyclic thiomethyl-3-cephem-4-carboxylic acids starting from suitably 7 beta -phenyl-acetamido-3-methyl-3-cephem-4-carboxylic acid 1 beta -oxide.