Process for 3-chloro cephalosporin nucleus
US4281117A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1980 |
| Grant date | Jul 28, 1981 |
| Priority date | — |
| Expiry date | Sep 4, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D501/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
7-Amino-3-hydroxy-3-cephem esters react with a chlorinating agent, e.g. phosgene, thionyl chloride and preferably PCl.sub.3 -DMF to provide 7.beta.-[(dimethylaminomethylene)amino]-3-chloro-3-cephem esters which on reaction with a carboxylic acid, a percarboxylic acid, or a phenol, having a pH in water of about 2-5, afford 7.beta.-formamido-3-chloro-3-cephem esters, and corresponding 2-cephem esters. Percarboxylic acids provide 7.beta.-formamido-3-chloro-3-cephem ester 1-oxides. The 7-formamido derivatives provide the 7-amino-3-chloro-3-cephem ester on acid hydrolysis. The 7-amino-3-chloro esters are useful for preparing antibiotics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.