Compounds of formula (I) in which: R.sup.1 is hydrogen or an organic substituent group; R.sup.2 is a fused bicyclic heterocyclic ring system of general formula (a) wherein R.sup.4 and R.sup.5 are independently hydrogen or one or more substituents replacing hydrogen atoms in the ring system shown; m is 2 or 3; p is 0, 1 or 2; and R.sup.3 is hydrogen, a salt-forming cation or an ester-forming group; and the symbol .dbd./.dbd. indicates that the double bond may be in either the E or Z configuration.
化合物的
化学式(I)中:R.sup.1 是氢原子或有机取代基团;R.sup.2 是一种融合的双环杂环环系统,其一般
化学式为(a),其中 R.sup.4 和 R.sup.5 独立地是氢原子或替代环系统中氢原子的一个或多个取代基;m 为2或3;p 为0、1或2;R.sup.3 是氢原子、形成盐的阳离子或酯化基团;符号 .dbd./.dbd. 表示双键可能是E构型或Z构型。