| 摘要 |
1,144,219. Esters of 7-aminocephalosporanic acids. BRISTOL-MYERS CO. 22 July, 1966 [22 July, 1965], No. 33129/66. Heading C2A. The invention relates to activated esters of 7-aminocephalosporanic acids of formula wherein R is C 2 to C 6 alkanoyl, N-phthalimido, benzoyl, naphthoyl, furoyl, thenoyl, nitrobenzoyl, halobenzoyl, methylbenzoyl, methanesulphonylbenzoyl or phenylbenzoyl; and to acid addition salts thereof with inorganic and organic acids. A typical compound is phenacyi #<SP>3</SP>-7-aminocephalosporanate and N-phthalimidomethyl - 7 - aminocephalosporanate. The salt may be the p-toluene sulphonic acid salt. The esters are prepared by reacting an acid of formula wherein R<SP>1</SP> is H or 2-thienylacetyl with a compound of formula R-CH 2 -X wherein X is halogen and R is as defined above and, when R<SP>1</SP> is the 2-thienylacetyl radical, removing said radical by deacylation with an amidase, e.g. that produced by E. coli or Arthrobacter viscosus. Alternatively, the compounds are prepared by treating with p-toluenesulphonic acid an activated ester made from 7-(N-tritylamino)-cephalosporanic acid and an alcohol of formula HOCH 2 R wherein R has the above meaning. Cephalosporins are produced by reacting an ester of 7-aminocephalosporanic acid according to the invention with an acylating agent for a primary amine group and thereafter hydrolysing the resultant acylated ester with an alkaline hydrolysing agent such as sodium thiophenoxide. |
