Synthesis and antimicrobial properties of cephalosporin derivatives substituted on the C(7) nitrogen with arylmethyloxyimino or arylmethyloxyamino alkanoyl groups

Some 7-aminocephalosporanic acid (7-ACA) derivatives substituted on the C(7 ) nitrogen with 2-(arylmethyloxyimino)propionyl (3a-f), 2-(arylmethyloxyami no)propionyl (4a-d) and (arylmethyloxyamino)acetyl (2a-d) moieties were syn thesized by reaction of the appropriate acylating agents with 7-ACA protect ed as a t-butyl ester, followed by removal of the t-butyl protecting group. The new compounds; tested in vitro for their antimicrobial activity agains t Gram-positive and Gram-negative bacteria, proved to possess a modest acti vity directed only against Gram-positive microorganisms. (C) 1999 Elsevier Science S.A. All rights reserved.