Ferulic Acid Fatty Esters Synthesis: Physical and Biochemical Characteristics

Abstract

Ferulic acid is a natural antioxidant and is found particularly in the cell walls of plants. Its esters have continued to receive great attention among researchers because of their wide range of therapeutic potentials. This realization has prompted us to synthesize rarely known long chain fatty acids derived esters of ferulic acid. Thus, our efforts have produced methyl 4-O-hexadecanyl ferulate, methyl 4-O-octadecanyl ferulate, methyl 4-O-octadec-Z-9-enyl ferulate and methyl 4-O-undec-11-enyl ferulate as fatty acid esters and methyl ester (9-COOCH3), using dicyclohexyl carbodiimide as an activating reagent in the presence of a catalytic amount of 4-dimethylaminopyridine. Reactions occurred at two reactive esterification sights, 9-COOH (methyl ferulate) and HO-C-4 (fatty acid esters) of methyl ferulate. Desired products were obtained in quantitative yields. The phenolic hydroxyl showed slow progress of esterification reactions and has taken longer reaction time to complete as compared to aliphatic alcohols. Two additional products in excellent yields, a dimer (4-O-9') and a 4-C-OCH3 were also prepared along with esters. The chemical structures of compounds have been elucidated by FTIR, 1H and 13C NMR and positive HRESI-MS spectroscopic data. The pharmacological (anti-oxidant and anti-cancer) studies have produced exciting results. The present research may help us to study structure-activity relationship. Fatty acid incorporated molecules of ferulic acid are rarely reported in literature.