A process for preparing a compound having the formula: ##STR1## wherein R is selected from the group consisting of C.sub.3 -C.sub.6 -cycloalkyl, C.sub.3 -C.sub.6 -cycloalkylmethyl, C.sub.1 -C.sub.6 -alkyl, allyl and 2-methoxyethyl, by reacting: ##STR2## under defined conditions with subsequent stepwise reactions of the respective intermediate compounds with a malonic acid diester, POCl.sub.3, and by heating the final intermediate in a high boiling solvent.
一种制备具有公式:##STR1##其中R选自C.sub.3-C.sub.6-环烷基,C.sub.3-C.sub.6-环烷基甲基,C.sub.1-C.sub.6-烷基,烯丙基和2-甲氧基乙基的化合物的方法,包括在定义条件下反应:## STR2 ## 随后逐步反应各中间化合物与
丙二酸酯、POCl.sub.3,并通过在高沸点溶剂中加热最终中间体。