Metal-Free C-H Thiomethylation of Quinones Using Iodine and DMSO and Study of Antibacterial Activity

摘要

A novel,transition metal-free,molecular iodine mediated method for thiomethylation of quinones,using dimethyl sulfoxide(DMSO)as a benign thiomethylating agent is described.This greener reaction protocol leads to selective mono thiomethylation in low to high yield and tolerates a range of substituent groups.Preliminary antibacterial evaluation of thiomethylated quinones,carried out against methicillin resistant Staphylococcus aureus shows promising results.One of the compound 3’-methyl-6-(methylthio)-[1,1’-biphenyl]-2,5-dione exhibited antimicrobial activity even against clinical isolates of S.aureus and vancomycin-intermediate Staphylococcus aureus(VISA).