Synthesis and biological evaluations of some novel phosphorus compounds containing chromene ring

Abstract

In continuation of our program research on the synthesis of new biologically active heterocyclic organophosphorus compounds, we herein reported the synthesis of phosphorus heterocyclespossessing multi heterocyclic rings via treatment of 2-imino-2H-chromene-3-carboxamide with some variable phosphorus reagents and evaluated their antioxidant activities. The starting material 2-imino-2H-chromene-3-carboxamide (1) was prepared by cyclization of salicylaldehyde with cyanoacetamide in absolute ethanol containing a few drops of triethylamine (Scheme 1). The presence of two active nucleophilic and two electrophilic sides in the molecule of 2-imino-2H-chromene-3-carboxamide (1) provides alternative opportunities in the direction of the reaction with electrophilic and nucleophilic phosphorus reagents. Its synthetic precursor opens wide opportunities for the use of chromene system in the synthesis of diverse fused phosphorus heterocyclic compounds.