Synthesis and spectral characterization of metal complexes of Schiff base derived from indole-3-carboxaldehyde and L-histidine as potent biocides

Abstract

This research work presents the structural features and biological activities of a novel series of Mn/Fe/Co/Ni/Cu/Zn(II)-(indal-L-his) complexes obtained from indole-3-carboxaldehyde (indal) and L-histidine (L-his). The prepared compounds were characterized by elemental analysis, molar conductivity, magnetic, IR, UV–vis, ¹H NMR, mass and ESR spectroscopies, powder XRD and TGA studies. Electronic spectra and magnetic moment data suggest an octahedral geometry for [Mn(II)-(indal-L-his)₂(H₂O)₂] and [Fe(II)-(indal-L-his)₂(H₂O)₂], tetrahedral geometry for [Co(II)-(indal-L-his)₂] and [Zn(II)-(indal-L-his)₂] and square planar geometry were assigned for [Ni(II)-(indal-L-his)₂] and [Cu(II)-(indal-L-his)₂]. The photocatalytic efficiency was explored for the synthesized compounds. In vitro antimicrobial activity of synthesized compounds was analyzed against some selected Gram-positive and Gram-negative bacterial and fungal species by disc diffusion technique. The compounds have shown to reveal excellent antibacterial and antifungal activity.

Graphical Abstract

Keywords:

• Indole-3-carboxaldehyde
• L-histidine
• NMR
• Mass
• TGA
• Photocatalytic efficiency

Acknowledgements

Authors thank SAIF, IIT-Bombay, Mumbai, STIC, Kochi, CSIR-NIIST, Thiruvananthapuram, CLIF, University of Kerala, Thiruvananthapuram, CEPC, Kollam, Kerala, India for extending their instrumental technical supports.

Disclosure statement

No potential conflict of interest was reported by the authors.