Pyrazolo[3,4-d] [1,2,3]triazole-1-carboxamides and 5-alkylamino pyrazolo[3,4-d]oxazoles: synthesis and evaluation of the in vitro antifungal activity

A series of N-alkyl-N'-(4-diazo-5-pyrazolyl)-ureas (4) was thermally and photochemically converted into pyrazolo [3,4-d][1,2,3]triazole derivatives (5,6) and 5-alkylaminopyrazolo[3,4-d]oxazoles (7) respectively. The products were tested for in vitro antifungal activity against Fusarium culmorum, Botrytis cinerea, Phoma betae, Pythium ultimum, Sclerotinia minor and Rhizoctonia solani. The MIC and ED50 values of compound (6) against some of the test fungi were comparable to those of the reference fungicides iprodione and mancozeb.