Synthesis,characterization, biological screening and molecular docking studies of 2-aminonicotinaldehyde (ANA) and its metal complexes

The biological and optical importance of the o-aminoaldehyde family of ligands inspired us to evaluate the coordination properties and biological activities of 2-aminonicotinaldehyde (ANA). Here, we report the synthesis, characterization, biological screening and molecular docking studies of ANA and its metal complexes of Ni(II), Pd(II), Co(II) and Cu(II) using various analytical and spectroscopic techniques. The single crystal X-ray diffraction studies of ANA explain the solid-state assembly and an interesting supramolecular herring bone stacking pattern by classical N–H···O/N intra/inter molecular and non-classical C–H···O/N intermolecular H-bonding. ANA and its metal complexes were screened for in vitro anticancer, antimicrobial and anti-oxidant activities. Anticancer activity was tested against HeLa, MCF-7 and HEK293 human cancer cell lines. The Ni(ANA)₂Cl₂] complex showed good activity against HeLa and MCF-7, the Pd(ANA)₂Cl₂] and Cu(ANA)₂Cl₂] complexes against HeLa, and the Co(ANA)₂Cl₂] complex against MCF-7. In antimicrobial screening, the Co(ANA)₂Cl₂] and Cu(ANA)₂Cl₂] complexes were proved to be potent antibacterial and antifungal agents. The anti-oxidant activity of these complexes was investigated through DPPH radical assay, and it was found that all the complexes have good radical scavenging capability. Molecular docking studies were also carried for all the metal complexes against EGFR as a target protein by using Autodock, and the results strongly correlated with the anticancer activity.