Antioxidative activity of 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid.

The (-)-(1S, 3S) isomer of 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid was synthesised by Pictet-Spengler condensation of tryptophan with acetaldehyde. It was evaluated for its antioxidative activity in the linoleic acid autooxidation system by the ferric thiocynate method. Butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), and alpha-tocopherol were used as the reference standards. The compound showed moderate antioxidative activity and also synergistic effect with the reference standards. The synergistic effect was in the increasing order of BHT, alpha-tocopherol and BHA. The synergistic effect was higher at higher concentrations studied.