1,3-Dipolar cycloaddition of uracil derivatives with nitrile oxides: Synthesis of [1,2,4]oxadiazolo[4,5-c]pyrimidine-5,7(6H)-dione derivatives

Abstract

An efficient method of synthesizing bicyclic fused [1,2,4]oxadiazolo[4,5-c]pyrimidine-5,7(6H)-dione derivatives was developed through a [3 + 2] cycloaddition of uracil derivatives and nitrile oxides. In the one step reaction, CN and CO bonds were constructed, the target compounds were efficiently obtained in good yields. The method represents a valuable way to obtain highly functional fused bicyclic heterocycle derivatives in a simple, rapid and practical manner. The method fusing bicyclic heterocycles can be applied for modification of uracil analogues that may have potential biological activities.