The invention provides novel antibiotic compounds which are 6.beta.-acylamidopenam-3-carboxylic acids and non-toxic derivatives thereof, characterized in that the acylamido group has the structure ##EQU1## WHERE R is a hydrogen atom or an organic group and R.sup.a is a hydrogen atom or an acyl group. The compounds are syn isomers or exist as mixtures containing at least 75% of the syn isomer. These antibiotic compounds possess high antibacterial activity against a range of gram positive and gram negative organisms coupled with particularly high stability to .beta.-lactamases produced by various gram negative organisms. The invention is also concerned with the administration of the compounds.
本发明提供了一种新的抗生素化合物,其为6-β-酰胺基青霉烷-3-
羧酸及其非毒性衍
生物,其特征在于酰胺基具有以下结构:##EQU1## 其中R为氢原子或有机基团,R.sup.a为氢原子或酰基。该化合物为同构体或存在至少75%的同构体混合物。这些抗生素化合物对一系列革兰氏阳性和革兰氏阴性微
生物具有高度的抗菌活性,并且对各种革兰氏阴性微
生物产生的β-内酰胺酶具有特别高的稳定性。本发明还涉及该化合物的使用。