The study assessed the DPPH radical-scavenging abilities of 2,3,4-trihydroxybenzoic acid and its methyl ester, finding that both were more effective in acetonitrile, with the ester being particularly effective in methanol.
The methyl ester produced a novel benzocoumarin-type dimer when oxidized with o-chloranil in acetonitrile, verified by spectroscopic analysis.
The improved radical-scavenging activity of the ester is likely linked to the formation of this dimer in certain solvents.