Synthesis of 2-Methoxy-4-(methylsulfanyl)benzoic Acid — An Intermediate Product in the Preparation of the Cardiotonic Drugs Sulmazole and Isomazole

Abstract

Readily available 4-methyl-3-nitrobenzenesulfonic acid and 2-methyl-5-nitrophenol were used to develop two alternative approaches to the synthesis of 2-methoxy-4-(methylsulfanyl)benzoic acid in total yields of 17% and 37%, respectively. The synthesis starting from 2-methyl-5-nitrophenol is more process-oriented and can be used in the resynthesis of Sulmazole and Isomazole.