Computational Studies and Geometry Optimization of Antidiabetic Drug, N,N-dimethylimido Dicarbo Nimidic Diamide

Abstract

Metformin (N,N-dimethylimidodicarbonimidicdiamide) is a biguanide-class oral antidiabetic medication. It is the first-line therapy for type 2 diabetes in adults who are overweight or obese, as well as those who have normal renal function. The in silico nuclear resonance magnetic spectroscopy of metformin was performed using ACD/I-lab. The chemical shifts of the methyl protons labelled 6 and 7 appeared as a singlet at 3.03 ppm while the chemical shifts of the amino protons labelled 3, 5, 10 and 11 appeared as a singlet at position 10.16, 6.66, 8.57 and 8.38 ppm respectively. Chemical changes of 38.77 ppm were seen in the methyl carbons at positions 6 and 7, whereas chemical shifts of 158.20 and 159.10 ppm were seen in the imine carbons. All conformational analysis (geometry optimization) study was performed on a window based computer using Argus lab software. The metformin structure was generated by Argus lab, and minimization was performed with the semi-empirical Parametric Method 3 (PM3). The geometry convergence function in Argus lab software was used to find the minimal potential energy. The highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and electrostatic potentials (ESP) mapping density were seen using surfaces. The minimum potential energy calculated using geometry convergence function in Argus lab software was found to be 41.537840 kcal/mol. This energy minimum is the most stable conformation of the molecule.