Synthesis, Characterization and Antioxidant Activity of Cinnamaldehyde Derived Schiff Base

Tai, Qiu Yi (2023) Synthesis, Characterization and Antioxidant Activity of Cinnamaldehyde Derived Schiff Base. Final Year Project (Bachelor), Tunku Abdul Rahman University of Management and Technology.

Text Tai Qiu Yi_Full Text.pdf Restricted to Registered users only Download (3MB)

Abstract

This project aims to study the antioxidant activity of the ligand and to determine whether it will produce synergistic antioxidant activity. In this project, a new Schiff base ligand named (Z)-N-phenyl-2-((E)-3-phenyl allylidene) hydrazine-1-carbothioamide (PTCA) was synthesised via condensation reaction of 4-phenyl-3-thiosemicarbazide and trans-cinnamaldehyde in 1:1 molar ratio. Ligand synthesised were characterized by Fourier Transform Infrared (FTIR) spectroscopy, melting point apparatus, Differential Scanning Calorimetry (DSC), Ultraviolet-Visible (UV-Vis) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Through the characterisation, it was found that the PTCA Schiff base existed predominantly in thione (C=S) tautomer in both solid and liquid states. In addition, the synthesized ligand, PTCA, were further evaluated for their antioxidant activity via 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activity assay. Based on the result, the synthesized compound, PTCA, had the IC50 value of 105.6 μg/ml which is higher than the obtained IC50 value of ascorbic acid, which was 10.39 μg/ml. This indicated that PTCA exhibited weaker antioxidant power than ascorbic acid. Thus, PTCA was not the potential antioxidant alternative of ascorbic acid.