New efficient synthesis and bioactivity of homoisoflavonoids

Abstract

Two naturally occurring homoisoflavonoids (3h,3i) and nine analogs (2a-2i) have been synthesised from appropriately substituted phenols thorough 1-(2-hydroxyphenyl)-3-phenylpropane-1-ones (1a-1i). The anti-oxidant and anti-fungal activities were determined by superoxide (NBT) and Agar cup method respectively. The reaction of 1-(2-hydroxyphenyl)-3-phenylpropane-1-ones with triethylorthoformate and 70% perchloric acid followed by aqueous hydrolysis of the intermediate perchlorates, the corresponding homoisoflavones (2a-2i) are obtained in excellent yields. Thereafter, 2a-2i has been converted into homoisoflavanones by subjecting to catalytic hydrogenation. This methodology has been applied for the first time for the synthesis of (±)- dihydrobonducellin (3h) and (±)-2′-methoxydihydrobonducellin (3i), which have been isolated from Caesalpinia pulcherrima. ©ARKAT USA, Inc.