A simple two step synthesis of 6, 8-dihydroxy-3- (3',4'-dihydroxyphenylethenyl)‎ isocoumarin

الملخص EN

The title isocoumarin (3) isolated recently from the underground parts of the plant Achyls triphylla, by other authors, has been synthesized.

Direct reaction of 3,5-dimethoxyhomophthalic acid (4) with 3,4-dimethoxycinnamoyl chloride (5) afforded 6,8-dimethoxy-3-(3',4'-dimethoxyphenylethenyl)isocoumarin (6).

Complete demethylation of compound (6) was effected using boron tribromide in refluxing dichloromethane to give the title isocoumarin (3) in reasonable yield.