The present invention relates to compounds of the general formula I ##STR1## wherein R.sup.1 denotes formyl or (C.sub.1 -C.sub.3)-alkylcarbonyl, R.sup.2 denotes the group CH.sub.2 --CH(A)--B, wherein A represents hydroxyl and B represents hydrogen or methyl, or A represents hydrogen and B represents hydroxymethyl, or the group COO--CH(X)--CH.sub.2 --D, wherein X represents hydrogen or methyl and D represents chlorine or bromine, or X represents hydrogen and D represents chloromethyl or bromomethyl, and R.sup.3 denotes (C.sub.1 -C.sub.4)-alkyl, processes for their preparation and their use.
本发明涉及一般式I的化合物,其中R.sup.1表示甲酰基或(C.sub.1 -C.sub.3)-烷基羰基,R.sup.2表示基团CH.sub.2 --CH(A)--B,其中A代表羟基,B代表氢或甲基,或A代表氢,B代表羟甲基,或基团COO--CH(X)--CH.sub.2 --D,其中X代表氢或甲基,D代表
氯或
溴,或X代表氢,D代表
氯甲基或
溴甲基,R.sup.3表示(C.sub.1 -C.sub.4)-烷基,其制备方法及其用途。