Compounds are described of the formula (II): ##STR1## wherein R.sub.1 is a group such that CO.sub.2 R.sub.1 is an ester group; A.sub.1 is a hydrogen atom; and A.sub.2 is a group CR.sub.2 R.sub.3 R.sub.4 wherein R.sub.2 is a hydrogen atom or a hydroxyl group; R.sub.3 is a hydrogen atom or a lower alkyl group; and R.sub.4 is a hydrogen atom or a lower alkyl group, a benzyl group, a phenyl group or is joined to R.sub.3 to form part of a C.sub.5-7 carboxylic ring or is a group of the formula CH(OH)R.sub.5 or CHX wherein R.sub.5 is a hydrogen atom or lower alkyl group and X is an oxygen atom or a CR.sub.6 R.sub.7 group where R.sub.6 is a hydrogen atom or a lower alkyl, phenyl, CN, CO.sub.2 R.sub.8 where R.sub.8 is a lower alkyl, phenyl or benzyl group and R.sub.7 is a hydrogen atom or a lower alkyl group or is joined to R.sub.6 to form part of a C.sub.5-7 carbocyclic ring. These compounds have been found to possess antibacterial properties. The preparation of these compounds is described.
该文描述的是化合物的公式(II):##
STR1##其中R.sub.1是一个基团,使得CO.sub.2 R.sub.1是一个
酯基团;A.sub.1是
氢原子;A.sub.2是一个基团CR.sub.2 R.sub.3 R.sub.4,其中R.sub.2是
氢原子或羟基;R.sub.3是
氢原子或低
碳基基团;R.sub.4是
氢原子或低
碳基基团、
苄基团、
苯基团或与R.sub.3结合形成C.sub.5-7羧基环的一部分,或者是公式CH(OH)R.sub.5或CHX的基团,其中R.sub.5是
氢原子或低
碳基基团,X是
氧原子或CR.sub.6 R.sub.7基团,其中R.sub.6是
氢原子或低
碳基、
苯基、CN、CO.sub.2 R.sub.8(其中R.sub.8是低
碳基、
苯基或
苄基团),R.sub.7是
氢原子或低
碳基团,或与R.sub.6结合形成C.sub.5-7
碳环。这些化合物具有抗菌性能。文中还描述了这些化合物的制备方法。