Synthesis of novel chiral metal complexes derived from chiral thiosemicarbazide ligands as potential antioxidant agents

Abstract

Two new chiral thiosemicarbazide ligands and their Cu (II), Ni (II), Pd (II), and Zn (II) complexes were synthesized and characterized by nuclear magnetic resonance (NMR) (only for ligand), Fourier transform infrared (FT‐IR), ultraviolet visible (UV‐Vis), mass, and elemental analysis. The antioxidant activity of ligands and their metal complexes was examined. It was found that the antioxidant activity of metal complexes was better than their ligands. In addition, the antioxidant activity, as reflected by free radical scavenging, was evaluated. Besides, Pd (II) complexes exhibited better antioxidant activity than Ni (II), Cu (II), and Zn (II) complexes. Therefore, complexes (3a‐Pd and 3b‐Pd) can be used as an antioxidant agent or antioxidant test standard.

Design and antiproliferative and antioxidant activities of furan-based thiosemicarbazides and 1,2,4-triazoles: their structure-activity relationship and SwissADME predictions

“…The NH (H-6, H-7, and H-9) protons of thiosemicarbazide (-NH-NH-C=S-NH-) derivatives 1-12 were detected at δ 9.11-10.03, 10.34-11.29, and 9.55-10.52 ppm, respectively. In the a study [25], 1 H NMR protons data in the thiosemicarbazide scaffold were found to be compatible with the chemical shift values of thiosemicarbazide protons in this study. The resonance of proton H-7 in the 1,2,4-triazole derivatives at 13.97-14.22 ppm and the disappearance of the H-6 and H-9 protons in the thiosemicarbazide derivatives in the cyclization products were de nite evidence of the synthesis of 1,2,4-triazole derivatives.…”

Citrus Limon L. Peel Powder Incorporated Polyvinyl Alcohol/Corn Starch Antioxidant Active Films

“…DPPH free radical scavenging and ABTS cation radical scavenging assays were conducted as described by Ferreira et al (2014). The procedure defined by Başaran et al (2019) was used to determine the β-Carotene-linoleic acid and cupric reducing antioxidant capacity (CUPRAC) of films with some adjustments. Solutions of films were prepared at 50, 25, 12.5 and 6.25 ppm concentrations.…”

Crystal structures of bis[1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O)cobalt(III)-tetra(thiocyanato-κN) cobalt(II) methanol solvate, bis{1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O}nickel(II) bis(thiocyanate) and (1-(1-hydroxypropan-2-ylidene)thiosemicarbazide-κ3S,N,O)bis(thiocyanato-κN)zinc(II)

“…Thus, the sulfur atom can bind to the metal in its thione form or in its thiolate form [29][30][31]. There are also complexes in which the sulfur atom remains uncoordinated [32,33]. In this article, we report the synthesis and structural characterization of the Co(II/III), Ni(II) and Zn(II) complexes of 1-(1-hydroxypropan-2-ylidene)thiosemicarbazide (H2L) (Scheme 1).…”