Synthesis and Antifungal Activity of [1, 2, 4]Triazolo-[1, 5-<i>c</i>]pyrimidine Derivatives

Abstract

Condensation of amidinohydrazoneswith ethoxymethylenemalononitrile gave 2, 3-dihydro [1,2,4]triazolo [1,5-c]pyrimidines in moderate to high yields.Of the variously substituted amidinohydrazones, aldehyde 4-monosubstituted ones were most reactive in the condensation, regardless of the nature of the 4-substituent.The 2,3-dihydro compounds were oxidized with iron(III) chloride in aqueous acetic acid or with iodine in ethyl alcohol to give the corresponding [1,2,4] triazolo [1,5-c] pyrimidines.Thirty-eight compounds were subjected to fungicidal screening tests, which showed no or weak activity against test organisms.