SYNTHESIS OF SOME NEW HETEROCYCLIC COMPOUNDS FROM BENZOPYRANO[2,3-c]PYRAZOL-3-ONE DERIVATIVES

Abstract

The reaction of benzopyrano[2,3-c]pyrazol-3-one (1) with some active halo compounds, afforded compounds 4, 8 and 12, respectively. The cyanoethyl derivative 19 was synthesized and treated with active methylenes and sulfur or benzoylisothiocyanate and phenacyl bromide, to give compounds 24a,b and 27. Compounds 25a,b and 28 were obtained through the reaction of compounds 24a,b with acrylonitrile or compound 27 with maleic anhydride. Thiation of compound 1 afforded the corresponding thio derivative 29. The reaction of 4-benzylidene-2-methyloxazolin-5-one with compounds 1 or 29 gave products 30a,b , respectively.