Synthesis, Biological and In Silico Studies of (1H-Indol-3-ylmethylene)-naphthalen-1-ylamine and its Os(VIII), Pd (II), Ni(II), Cr (III) and Fe(III) Complexes

Abstract

(1H-Indol-3-ylmethylene)-naphthalen-1-ylamine, INDNA was synthesized by the condensation of 1- naphthylamine with indole-3-carboxaldehyde. Additionally, the complexes of Os(VIII), Pd (II), Ni(II), Cr (III) and Fe(III) were synthesized. ESI-MS spectroscopic techniques, 1H and 13C NMR, UV-VIS, IR and elemental analysis were used to characterize the ligand and metal complexes. According to spectral data, INDNA binds as a bidentate ligand to the metal ions via the nitrogens in the imine and indole chains. The ligand to metal stoichiometry of the compounds is 2:1. The metal complexes exhibit tetrahedral geometry. The ligand and complexes were tested for their in vitro antibacterial activity against a range of microorganisms namely: Salmonella sp., Staphylococcus sp. (vancomycin resistant), Candida albicans, Klebisella sp. (pneumonia), sewage-producing sp., clinical sp., and typed sp. using agar well diffusion method. Compared to the ligand, the complexes were found to be more active against the tested bacteria. The antifungal activity of INDNA was enhanced on complexing with Pd (II) ion. The drug likenesses were also determined using molecular docking studies.