Synthesis, characterization, electrochemical behavior, molecular simulation studies and in vitro toxicity assessment of new metal Schiff base complexes derived from 3‑methoxy-2‑hydroxy-benzaldehyde and allylamine

•Two mononuclear Schiff-base complexes Co(III) and Ni(II) containing an allylamin ligand were synthesized.•The metal complexes characterized by spectral methods and the crystal structures confirmed by X-ray diffraction.•Electrochemical investigations exhibited irreversibly redox behavior.•Synthesised compounds were evaluated for their in vitro anti-cancer activities against SW-480 cell line.•Cytotoxic activity proved, that the type of metal plays a key role for the cytotoxic effect of Schiff base compounds. In this research, a series of new Schiff base complexes of CoL3 (1) and NiL2 (2) were derived from 3‑methoxy-2‑hydroxy-benzaldehyde with 3-amino‑prop-1-ene (allylamine). The functional groups were elaborately demonstrated using elemental analyses, Mass spectra, Fourier transform infrared (FT-IR), UV–Vis spectroscopy and single-crystal X-ray diffraction technique. X-ray diffraction results revealed that both complexes crystallized in the triclinic system with a space group of P1¯. The structural studies exhibited octahedral and square planar geometry for (1) and (2) around the central metal ion. Moreover, the redox behavior of the complexes was evaluated in methanol by cyclic voltammetry (CV) technique. The electrochemical behavior of the complexes showed the electronic effects of the groups on redox potential for both complexes. The synthesized allyl-based metal complexes were tested for anticancer activity in the human colorectal (SW-480) cancer cell line. In vitro cell proliferation was studied by microculture tetrazolium technique (MTT colorimetric assay) which indicated that all treatment groups are capable of decreasing the proliferation rate of SW-480 cells. The cytotoxic measurements showed strong inhibitory activity against cancer cells for all ligands and complexes in a concentration-dependent manner. Pharmacophore of novel colorectal cancer compounds was also explored. Molecular docking studies of our Schiff bases complexes was carried out to bind to B-DNA . [Display omitted]