This invention relates to the compounds of the formula [I] which are useful for the treatment of cataracts, and the synthetic intermediates of the formula [II], ##STR1## wherein R.sup.1 is hydroxy which can be protected by a hydroxy protective group; R.sup.2 is lower alkyl; R.sup.3 is hydrogen, lower alkyl, hydroxy, which can be protected by a hydroxy protective group, or lower alkoxy, and the said lower alkyl can be substituted by hydroxy, which can be protected by a hydroxy protective group, amino or lower alkylamino; R.sup.4 is carboxy which can be converted into ester or amide; tetrazolyl; phosphono which can be converted into ester or amide; or sulfonyl which can be converted into ester or amide; R.sup.5 is cyano or lower alkoxy; A is alkylene; B is C.dbd.O, C.dbd.S or CH.sub.2, and is single bond or double bond.
这项发明涉及具有以下式[I]的化合物,这些化合物对白内障的治疗有用,并且具有以下式[II]的合成中间体,其中R.sup.1是可以通过羟基保护基保护的羟基;R.sup.2是较低的烷基;R.sup.3是氢、较低的烷基、羟基(可以通过羟基保护基保护)、或较低的烷氧基,所述较低的烷基可以被羟基(可以通过羟基保护基保护)、
氨基或较低的烷基
氨基取代;R.sup.4是可以转化为酯或酰胺的羧基;
四唑基;可以转化为酯或酰胺的
膦酸基;或可以转化为酯或酰胺的磺酰基;R.sup.5是
氰基或较低的烷氧基;A是烷基;B是C.dbd.O、C.dbd.S或CH.sub.2,并且是单键或双键。