3-(2 ' ,3 ' ,4 ' -Trimethoxyphenyl)isocourmarin (7) was synthesized by the
condensation of homophthalic acid (5) with 2,3,4-trimethoxybenzoyl chloride
(6) which on alkine hydrolysis gave the keto-acid (8). (dl)-3-(2 ' ,3 ' ,4
' -Trimethoxyphenyl)-3,4-dihydroisocoumarin (11) was obtained by reduction
of the keto-acid (8) to racemic hydroxy-acid (10) followed by cyclodehydra
tion using acetic anhydride.