##STR1## A compound of general formula (I), wherein X=CH.sub.2, O, S or NR.sup.4, and Y=formula (II): where R.sup.1 =H, lower alkyl or an aryloxyalkyl group, wherein the aryl group is optionally substituted by alkyl, alkoxy, hydrogen, alkyl substituted by hydrogen, and n is an integer between 0 and 5, and Z=O, S or NR.sup.2 ; wherein R.sup.2 =H, lower alkyl, hydroxy, amino cyano or acyl, R.sup.3 =H, or lower alkyl, and R.sup.4 =H, lower alkyl, or lower acyl, and pharmaceutically acceptable salts thereof.
通式(I)的化合物,其中X=CH.sub.2、O、S或NR.sup.4,而Y为通式(II):其中R.sup.1=H、低碳基或芳氧基烷基,其中芳基可以选择地被烷基、烷氧基、氢、被氢取代的烷基取代,n为0到5之间的整数,而Z=O、S或NR.sup.2;其中R.sup.2=H、低碳基、羟基、
氨基、
氰基或酰基,R.sup.3=H或低碳基,而R.sup.4=H、低碳基或低酰基,以及其药学上可接受的盐。