Transformation of Substituted 5-Amino-1,3-oxazole-4-carbo-nitriles into New 3,4,5-Triaminopyrazole Derivatives

摘要

Reactions of accessible 5-alkylamino- and 5-arylamino-1,3-oxazole-4-carbonitriles with hydrazine hydrate on heating involved a complex transformation sequence resulting in the formation of 3,4,5-triaminopyrazole derivatives. The structure of the products was confirmed by their cyclocondensation with acetylacetone, leading to 2-alkyl(aryl)amino-3-acylamino-5,7-dimethylpyrazolo[1,5-a]pyrimidines which were identified by NMR spectroscopy using COSY, NOESY, HMQC, and HMBC techniques.