Novel coordination compounds of Mn(II), Co(II), and Ni(II) with a new 4-(4-chlorocyclohexyl)- 2-oxo-6-(thien-2-yl)-1,2-dihydropyridine-3-carbonitrile ligand (L) have been synthesized. Melting point, elemental analysis, spectroscopic techniques (IR, 1H NMR, UV–Vis, and mass spectrometry), molar conductivity and thermo gravimetric analyzes were used to characterize the structures having the formulae: [Mn(L)2(H2O)2]SO4 (1), [Co(L)2(H2O)2]Cl2 (2), and [Ni(L)2(H2O)2]SO4·8H2O (3). The (L) reacts by 1 : 2 ratios with metal ions. Using infrared spectral data, it was noticed that L ligand coordinates as neutral NO bidentate along with the oxygen of keto-lactam (NH–C=O) and nitrogen of carbonitrile (C≡N) groups. Compounds 1–3 are electrolytic in nature according to the conductivity measurements. Magnetic moment and UV–Visible data depicts the octahedral environment around the studied metal ion. Moreover, Thermal analysis granted a concept around the decaying manner of L and its complexes. It also assessed the quantity of water molecules in the complexe’s inner and outer spheres. For all complexes an octahedral geometry has been proposed. TGA data shows the different degradations steps that have been utilized to calculate valuable thermodynamic and kinetic descriptors using two comparable methods. Furthermore, theoretical studies by DFT demonstrate a high consistent with the experimental data. Antimicrobial effectiveness of the L and its metal complexes were examined versus a diversity of pathogenic G(+ve) and G(–ve) bacteria and fungi.