An Improved Synthesis of 5,7-Dimethoxy-4-methylphthalide, A Key Intermediate in the Synthesis of Mycophenolic Acid

Abstract

An efficient synthetic pathway is described for 5,7-dimethoxy-4-methylphthalide, a key intermediate in the synthesis of mycophenolic acid and its analogues. The procedure starts from methyl 3,5-dimethoxybenzoate and involves five simple steps to give phthalide 3 in 55% overall yield.