A compound of formula (I) ##STR1## wherein R.sub.1 is selected from the group consisting of 2-thienyl, 2-furyl, 2-pyrrolyl, 1-methyl-2-pyrrolyl, 2-amino-1-thiazolyl and 5-isothiazolyl; R.sub.2 is selected from the group consisting of: ##STR2## and M is hydrogen or a pharmaceutically acceptable cation; wherein the oxyimino fragment (.dbd.N--OR.sub.2) in formula (I) is in the `anti` orientation.
化合物的式子为(I) ##STR1## 其中R.sub.1从2-
噻吩基,2-
呋喃基,2-
吡咯基,1-甲基-2-
吡咯基,2-
氨基-1-
噻唑基和5-
异噻唑基中选择; R.sub.2从以下组中选择: ##STR2## M是氢或药用可接受阳离子; 公式(I)中的氧
亚胺片段(.dbd.N--OR.sub.2)处于“反式”方向。