1,4‐Disubstituted bis‐chromenyl triazole hybrids 5a–m have been synthesized in a three‐step reaction sequence from 4‐(bromomethyl)‐2H‐chromen‐2‐ones 3a–m. The intermediate azides 4a–m underwent a regioselective 1,3‐dipolar cycloaddition with a 2H‐chromen‐2‐one linked acetylenic dipolarophile in the presence of Cu (II)/ascorbate/water/n‐butanol reaction medium. Three compounds 5h–j exhibited 6.25 μg/mL MIC against M. tuberculosis. Among the compounds screened for antifungal activity, lowest MIC of 6.25 μg/mL was observed for 5c against A. niger that also exhibited DNA cleavage observed by agarose gel electrophoresis. All the compounds were moderately active against both Gram‐positive and Gram‐negative bacterial strains. The cytotoxic effect of potent compounds on normal cells (V79 and HBL100) was assessed by MTT assay.

A novel method for the synthesis of 2-phenyl-5-(o-hydroxyphenyl)-pyridazin-3(2H)-ones and 5-(o-hydroxyphenyl)-pyridazin-3(2H)-ones has been found during the reaction of 4-bromomethylcoumarins with phenylhydrazine and hydrazinehydrate, respectively, under controlled alkaline conditions.