Synthesis of bioactive 4-oxo-4H-chromenes bearing heterocyclic systems from hydrazonecarbodithioic acid and thiocarbohydrazone

Condensation 4-oxo-4H-chromene-3-carboxaldehydes (1a,b) with acid hydrazine-carbodithioic acid and/or thiocarbohydrazide afforded hydrazonecarbodithioic acid 2, monothiocarbohydrazone 3a,b and bisthiocarbohydrazone 4, respectively. Heterocyclization of 2-4 via reaction with oxygen, sulfur and/or halogen reagents in different media yielded pyridazinethione 5; 1,3-thiazoles 7; pyrazoles 9-12; 1,2,4-thiadiazoles 8,13,14, and 23; 1,2,4-triazolethiones 15-17; 1,2,4-triazinethiones 18-22; imidazolethione 24 and pyrimidinethione 25 derivatives. Antifungal activity was screened for some the new synthesized compounds. Formulations of all products have been deduced by elemental analysis and spectral data (IR, 1H NMR and Mass spectroscopy).