| abstract |
Cephalosporin antibiotics of the formula <IMAGE> in which, for example, R is phenyl, hydroxyphenyl, halophenyl, thienyl, or furyl; R1 is hydrogen, carbamoyloxy, acetoxy, a lower alkyl substituted 1H-tetrazol-5-ylthio or 1,3,4-thiadiazol-5-ylthio group; and R2 is hydrogen or methyl; are highly active broad spectrum antibiotics especially useful in the treatment of infections attributable to the gram-negative microorganisms. |