Synthesis, Characterization and Bioactivity Studies of S-Allyl-β-N-(1-(4-methoxyphenyl)- ethylidene)dithiocarbazate and its Bis-chelated Cu(II), Ni(II) and Zn(II) Complexes

Abstract

The general formula M(mAp-sadtc)2 type of metal complexes (where M = Cu2+, Ni2+, Zn2+) were synthesized by reaction of S-allyl-β-N-(1-(4-methoxyphenyl)ethylidene)dithiocarbazate ligand [H-(mAp-sadtc)] with metal(II) acetate salts (M = Ni2+, Cu2+ or Zn2+). The bis-chelated metal complexes were synthesized by subsequent reaction of metal(II) acetate salts and dithiocarbazate ligand in 1:2 proportion, respectively. The metal complexes and dithiocarbazate Schiff base were characterized by available methods like elemental analysis, 1H NMR, UV-Vis spectroscopy, 13C NMR, FT-IR spectroscopy, molar conductance and magnetic moments. Both nitrogen atoms of azomethine moiety (C=N) and deprotonated thiolate sulfur of dithiocarbazate ligand coordinated to the central metal ion formed five-membered rings on chelation. The synthesized dithiocarbazate ligand [H-(mAp-sadtc)] (1) and its bis-chelated M(mAp-sadtc)2 complexes (2-4) were screened for bioactivity against bacterial strains. The antibacterial results show that the metal(II) complexes exhibited significantly prominent antibacterial activity than dithiocarbazate ligand. Among the synthesized bis-chelated metal complexes, Ni-complex exhibited prominent antibacterial and antifungal activity as compared to other metal(II) complexes and ligand.