Synthesis and evaluation of novel p-coumaric acid amides as antioxidants

An efficient, two steps synthesis of p-coumaric acid amides was described. The key intermediate, 3-(4-hydroxyphenyl) acryloyl chloride (2) was obtained by conversion of p-coumaric acid (1) to its acid chloride in presence of thionyl chloride. Further, coupling of different aminophenols and substituted aminophenols by base condensation reaction affords p-coumaric acid amides (2a-e). The newly synthesized compounds were characterized by spectral and elemental analysis data and studied for their antioxidant properties using 2,2-diphenyl-l-picryl hydrazyl (DPPH) radical scavenging assay and inhibition on human Low-density lipoprotein (LDL) assay. All the compounds exhibited good potent activity dose dependently. Butylated hydroxy anisole (BHA) was used as a reference antioxidant and also the comparative study with newly synthesized compounds was done.