Bioorganic synthesis, characterization and antioxidant activity of esters of natural phenolics and α-lipoic acid

Chemo-enzymatic synthesis of six esters of natural phenolics and alpha-lipoic acid was carried to produce novel compounds with potential bioactivity. The synthetic route was mild, simple, and efficient with satisfactory yields. The synthesized compounds were screened for antioxidant activities. The prepared derivatives exhibited very good antioxidant activities as determined by DPPH radical scavenging assay and inhibition of lipid oxidation in fish oil emulsion system. Among the prepared derivatives, three compounds exhibited radical scavenging activity similar to the reference antioxidants. BHT and alpha-tocopherol in the DPPH radical scavenging assay, where as in fish oil emulsion system, two derivatives showed activity, which was similar to the reference antioxidants. (C) 2011 Elsevier B.V. All rights reserved.