GREEN SYNTHESIS OF NEW AMINO ACID SCHIFF BASES AND THEIR BIOLOGICAL ACTIVITIES

Abstract

In this study, four new and two known amino acid Schiff base compounds derived from the condensation reaction of benzaldehyde, salicylaldehyde, pyrrole-2-carbaldehyde, pyridine-2-carbaldehyde, fluorene-2-carbaldehyde and terephthalaldehyde with 2-phenylglycine methyl ester hydrochloride have been synthesized by both conventional method and microwave irradiation protocol. The new compounds were characterized by FTIR, ¹H-NMR, LC-MS and electronic spectral studies. A comparative study between conventional heating and microwave irradiation has also been reported. Based on these results, with the microwave synthesis, the yield of the products was increased from 37% upto 96% as compared to conventional method. By microwave, reactions were completed within 5.5-8.5 minutes and the products were obtained in good to high yields, with reduced time, waste, and formation byproduct. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging effect were performed to determine antioxidant activities of the new compounds. All of the compounds exhibited significant activities in DPPH radical scavenging. 

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