| 摘要 |
Novel beta -lactam antibiotics are compounds of the formula: <IMAGE> wherein R is alkyl of up to 6 carbon atoms or, when A is oxygen, R is hydrogen; A is oxygen or -OCO-; Z is <IMAGE> R1 is hydrogen, acetoxy or S-Het; Het is 1,2,3-triazol-5-yl, 1-methyltetrazol-5-yl, 1,3,4-thiadiazol-2-yl or 2-methyl-1,3,4-thiadiazol-5-yl; and n is an integer from 0 to 8; or a readily-cleavable ester or physiologically-acceptable salt thereof. |
