3-Formyl-6-methylchromone may be used in the preparation of series of Schiff′s bases, via reaction with aromatic sulfonamides, such as sulfanilamide, homosulfanilamide, 4-aminoethyl-benzenesulfonamide, a pyrimidinyl-substituted sulfanilamide derivative, sulfaguanidine and 4-amino-6-trifluoromethyl-benzene-1,3-disulfonamide. It may be used in the preparation of Schiff base, which undergoes addition reaction with diethyl phosphite to afford bis[(1,2,4,3-triazaphospholyl)(chromonyl)aminomethylphosphonate] derivative and bis[(1,2,4,3-triazaphospholyl)(chromonyl)phosphorylamino-methylphosphonate] derivative.