Synthesis, Structural, and Antibacterial Studies of Some Mixed Ligand Complexes of Zn(II), Cd(II), and Hg(II) Derived From Citral Thiosemicarbazone and N-Phthaloyl Amino Acids

Abstract

A series of new mixed ligand complexes of Zn(II), Cd(II), and Hg(II) with cis-3,7-dimethyl-2,6-octadienthiosemicarbazone (CDOTSC; LH) and N-phthaloyl amino acids (AH) have been synthesized by the reaction of metal dichloride with ligands CDOTSC and N-phthaloyl derivative of DL-glycine (A₁H), L-alanine (A₂H), or L-valine (A₃H) in a 1:1:1 molar ratio in dry refluxing ethanol. All the isolated complexes have the general composition [M(L)(A)]. The plausible structure of these newly synthesized complexes has been proposed on the basis of elemental analyses, molar conductances, molecular weight measurement, and various spectral (IR, ¹H NMR, and ¹³C NMR) studies, and four coordinated geometries have been assigned to these complexes. All the complexes and ligands have been screened for their antibacterial activity.

Keywords:

• Mixed ligand complexes
• thiosemicarbazone
• N-phthaloyl amino acids
• antibacterial activity

Acknowledgments

The authors are greatly indebted to the head of the Chemistry Department, University of Rajasthan, Jaipur, for providing laboratory and instrumentation facilities. The authors are also grateful to Professor P. Bhatnagar, Zoology Department, University of Rajasthan, Jaipur, for his help during the antibacterial studies.

Notes

^aMolar conductance determined at 298 K in 10⁻⁴ M DMF solution.

^bDec.

^aNot sufficiently soluble to aquire a ¹³C spectrum.

^aAverage values from four experiments.