Novel Schiff base was synthesized from condensation reaction of metformin with [4- (Diethylamino) benzaldehyde (NBM). Different metal complexes were prepared using Pd(II), Pt(II), Cu(II) and V(IV) metal ions. All complexes showed the non-electrolytic behavior. So, the expected molecular formulas for complexes are [Pd(NBM)Cl2], [Pt(NBM)Cl2], [Cu(NBM)2Cl2] and [VO(NBM)2]. The cytotoxicity of (NBM) Schiff base and its metal complexes on human cancer cell line, MCF-7, was investigated. V(IV) and Cu (II) complexes showed potential blood-glucose lowering effect higher than the commercial metformin drug. VO(IV) complex has superior antioxidant activity more than the other synthesized compounds and the standard ascorbic acid. Molecular docking investigation proved the presence of interesting interactions between all synthesized compounds with the active site amino acids of EGFR tyrosine kinase (anticancer activity). The molecular docking of metal complexes observed effective inhibition for the specific mTOR protein that is expected to aid the growth of the COVID-19 virus.