GB1312175A - Process for preparing a 7-acylamino-3-acyloxymethyl delta3 - Google Patents

Abstract

1312175 Preparation of cephalosporins ELI LILLY & CO 13 Sept 1971 [14 Sept 1970] 42614/71 Heading C2A A process for preparing a 7-acylamido-3-acyloxymethyl #<SP>3</SP>-cephalosporin sulphoxide ester comprises reacting a 7-acylamido #<SP>3</SP>-desacetylcephalosporin sulphoxide ester with the anhydride of a saturated carboxylic acid under acid conditions. In such a process the 7-acylamido #<SP>3</SP>-desacetylcephalosporin sulphoxide ester may have the Formula I wherein R is the residue of the 7-acylamido group and R 1 is the residue of an ester protecting group. The anhydride has the Formula II wherein R 2 is selected from H, C 1 to C 7 alkyl and cycloalkyl having the Formula III wherein n is zero or an integer from 1 to 4 and R 3 is C 1 to C 3 alkylene. The 7-acyl group may be selected from the group IV where n is zero or an integer from 1 to 6 and R may be aryl containing 6-14 carbon atoms, cycloalkyl containing 4 to 8 carbon atoms and heterocyclic groups wherein the hetero atom is selected from O, S, N and combinations thereof, and substituted derivatives thereof or the group V wherein R 3 is C 1 to C 8 alkyl, C 2 to C 8 alkenyl and substituted derivatives thereof, or a group VI wherein n is 0 or an integer from 1 to 5, X is O or S and R 4 is selected from the group consisting of R 2 , C 2 -C 8 alkenyl and substituted C 2 to C 8 alkenyl derivatives or a group VII where Y may be amino, protected amino, hydroxy, C 1 -C 3 alkoxy, carboxyl and C 1 -C 3 alkanoyloxy or the acyl group may be phenyl- α,α-dimethylacetyl and substituted derivatives thereof.