Synthesis of Bioactive 4-Oxo-4H-Chromenes Bearing Heterocyclic Systems from Hydrazonecarbodithioic Acid and Thiocarbohydrazone

Abstract

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).

Keywords:

• Antifungal activity
• chromone
• heterocycles
• hydrazonecarbodithioic acid
• synthesis
• thiocarbohydrazone

Notes

*C, H, N elemental analysis for all products gave satisfied results.

**a,b indicated to the yields by methods A and B.