摘要 |
<p>Cyanoalkylureido cephalosporins of the formula wherein R is hydrogen, lower alkyl, phenyl-lower alkyl, diphenyl-lower alkyl, tri(lower alkyl)silyl, trihaloethyl, a salt forming ion, or the group ; R1 is hydrogen or methoxy; A is straight or branched chain alkylene or ; R2 is phenyl, 2-thienyl, or 3-thienyl; R3 is hydrogen or lower alkyl; R4 is hydrogen, lower alkyl, cycloalkyl, cycloalkenyl, cycloalkadienyl, phenyl, phenyl-lower alkyl, substituted phenyl, substituted phenyl-lower alkyl, or certain heterocyclic groups; R5 is hydrogen or lower alkyl: R6 is lower alkyl; and X is hydrogen, lower alkanoyloxy, , , or certain heterothio groups; are disclosed. These compounds are useful as antibacterial agents.</p> |