Synthesis and biological activities of 1-keto-3-carboxy-6,7-methylenedioxy-1,2,3,4-tetrahydronaphthalene derivatives

1-Keto-3-carboxy-6,7-methylenedioxy-1,2,3,4-tetrahydronaphthalene (I) was converted to its ester, 1-keto-3-carbmethoxy-6,7-methylenedioxy-1,2,3,4-tetrahydronaphthalene (II) which was treated with hydrazine hydrate to give 1-keto-3-hydrazocarbonyl-6,7-methylenedioxy-1,2,3,4-tetrahydronaphthalene (III). Compound (III) was condensed with various aromatic aldehydes to give corresponding 3-arylidene hydrazocarbonyl-6,7-methylenedioxy-1,2,3,4-tetrahydronaphthalene (IVa-h). On condensation with various substituted benzoxazones, compound (III) gave quinazoline-4-(3H)-one derivatives (Vi-k). Above condensation reactions were also carried out in a microwave oven at 10% energy. Compound (1) was treated with various benzhydrazides in presence of excess Of POCl3 to yield substituted oxadiazoles (VIa-b).