spartan'08  (Wavefunction inc)

Journal: Biometals

Article Title: Coordination chemistry suggests that independently observed benefits of metformin and Zn 2+ against COVID-19 are not independent

doi: 10.1007/s10534-024-00590-5

Figure Lengend Snippet: The metformin–Zn 2+ complex computed as “in vacuo”. The structure of the Zn 2+ complex of metformin was computed with the Spartan’08 program (Wavefunction, Inc., Irvine, CA) using density functional theory at the DFT B3LYP/6-31G* level. Zn 2+ forms a 1:1 bidentate complex through the lone electron pairs of imino nitrogens at the 2 and 4 positions of biguanide. Experimental evidence indicates that the 2 and 4 nitrogen positions remain protonated as computed. The charge on the complex is 2+; however, electron density is transferred from metformin to Zn 2+ . Counterions of a biological mixture are not shown. The metformin complex leaves unoccupied ligand-binding sites of Zn 2+ exposed to interactions with additional ligands. Many metabolites and macromolecules can undergo ligand exchange with the dissociable metformin–Zn 2+ (see text). Metformin can form a mixed (heteroleptic) complex with an endogenous biomolecule coordinated around the central metal cation. Zn 2+ is shown in green, carbon: black, nitrogen: blue, hydrogen: white. The surface potential gradation in the mesh is as indicated in Fig.

Article Snippet: The structure of the Zn 2+ complex of metformin was computed with the Spartan’08 program (Wavefunction, Inc., Irvine, CA) using density functional theory at the DFT B3LYP/6-31G* level.

Techniques: Functional Assay, Ligand Binding Assay