7-thiazolyl-acetamido-cephalosporin derivs. - useful as antibacterials in human and veterinary medicine e.g. against proteus vulgaris and bacillus subtilis

摘要

Cephalosporins of formula (I) and their pharmaceutically acceptable salts are new: R1=opt. protected amino; R3=opt. protected carboxy-R2= isobutyl and R4= acetoxy; or R=lower cycloalkyl or alkynyl and R4 = lower alkanoyloxy; or R2 = lower alkyl and R4 = 5-6C alkanoyloxy; or R2 = 2-6C alkyl, lower alkenyl, cycloalkyl or alkynyl and R4 = H, carbamoyloxy, thiadiazolythio (opt. lower alkyl substd.) or triazolylthio; or R2 = 2-6C alkyl lower cycloalkyl or alkynyl and R4=methyl-substd. tetrazolylthio; or R2 = lower alkyl, alkenyl, cycloalkyl or alkynyl and R4 = aroyloxy (opt. substd. by NO2 ro NH2), lower cycloalkylcarbonyloxy, arylcarbamoyloxy (opt. halo substd.), lower aralkanoyloxy, lower aryloxyalkanoyloxy substd. by lower alkoxy, thenoyloxy, tetrazolylthio substd. by 3-6C alkyl or benzothiazolylthio. Also new are the intermediates (IIa) and (IIb) and their salts. In (IIa) Q is 1-R7-tetrazol-5-ylthio with R7=3-6C alkyl; In (IIb) Q is OR4c with R4v = arylcarbamoyl (opt. halo substd.), lower aryloxyalkanoyl substd by alkoxy, thenoyl, lower cycloalkylcarbonyloxy or nitro-substd. aroyl.