NOVEL ONE-POT MULTICOMPONENT SYNTHESIS OFSUBSTITUTED 2,3-DIHYDRO-2-(6-(4-HYDROXY-6-METHYL-2-OXO-2H-PYRAN-3-YL)-7H-[1,2,4]TRIAZOLO[3,4-b][1,3,4]THIADIAZIN-3-YL)PHTHALAZINE-1,4-DIONES AND SUBSTITUTED3-[3-(N’-BENZYLIDENE-HYDRAZINO)-7H-[1,2,4]TRIAZOLO[3,4-b][1,3,4]THIADIAZIN-6-YL]-4-HYDROXY-6-METHYL-PYRAN-2-ONES

Abstract

A one-pot procedure has been developed for the synthesis of substituted 2,3-dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones by reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and phthalic anhydrides in acetic acid medium. Similarly, a one-pot, three-component synthetic procedure has been developed for substituted 3-[3-(N1-benzylidene-hydrazino)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones from 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and various aromatic aldehydes in absolute ethanol and a few drops of glacial acetic acid.