Heterocycles of biological importance. Part 1. Novel synthesis and biological activity study of 5-Alkyl and 5-Aryl-7-aminopyrazolo[1,5-<i>a</i>]-pyrimidines from allenic or acetylenic nitriles and 3-aminopyrazole
Allenicnitriles react with 3-aminopyrazole in ethanol or dimethylformamide to give 5-alkyl-7-aminopyrazolo[1,5-a]pyrimidines 5 of pharmaceutical interest in good yields. 3-Phenylpropynenitrile reacts with 3-aminopyrazole in a similar manner to give the aryl compound 8.