Studies on N-picolinoyl-N′-benzothioylhydrazide and its Zn(II) complex: Synthesis, structure, antibacterial activity, thermal analysis and DFT calculation

• A new complex [Zn(pbth)2] with N-picolinoyl-N′-benzothioylhydrazide has been reported.
• The complex is distorted octahedral involving NNS tridentate ligand.
• Structural data from X-ray are corroborated well with DFT calculations.
• The ligand and complex show antibacterial activity but lower than the standard drugs.
• Lower solid state conductivity of the complex shows weaker inter-molecular contact.

A new Zn(II) complex [Zn(pbth)2] (where Hpbth = N-picolinoyl-N′-benzothioylhydrazide) has been synthesized and characterized by elemental analyses, IR, UV–Visible and single crystal X-ray data. The distorted octahedral complex [Zn(pbth)2] crystallizes in monoclinic system with space group C2/c and is stabilized by various types of inter and intramolecular extended hydrogen bonding providing supramolecular framework. The optimized molecular geometry of N-picolinoyl-N′-benzothioylhydrazide (Hpbth) and the zinc complex in the ground state have been calculated by using the DFT method using B3LYP functional with 6-311 G(d,p){C,H,N,O,S}/Lanl2DZ basis set. The results of the optimized molecular geometry are presented and compared with the experimental X-ray diffraction data. In addition, quantum chemical calculations of Hpbth and the complex, molecular electrostatic potential (MEP), contour map and frontier molecular orbital analysis were performed. The solid state electrical conductivity and thermal behaviour (TGA) of the complex were investigated. The bioefficacy of the complex has been examined against the growth of bacteria in vitro to evaluate its anti-microbial potential.

A new Zn(II) complex [Zn(pbth)2] (where Hpbth = N-picolinoyl-N′-benzothioyl hydrazide) has been synthesized and characterized by elemental analyses, IR, UV–Visible and single crystal X-ray data. The distorted octahedral complex is stabilized by various types of inter and intramolecular extended hydrogen bonding providing supramolecular framework. The results of the optimized molecular geometry are presented and compared with the experimental X-ray diffraction data. The solid state electrical conductivity and thermal behaviour (TGA) of the complex were investigated. The bioefficacy of the complex has been examined against the growth of bacteria in vitro to evaluate its anti-microbial potential.Figure optionsDownload as PowerPoint slide