[01] Amaku Friday James, Department of Chemistry, Michael Okpara University of Agriculture, Umudike, Nigeria. [02] Otuokere Ifeanyi Edozie, Department of Chemistry, Michael Okpara University of Agriculture, Umudike, Nigeria. [03] Igwe Kalu Kalu, Department of Vet, Biochemistry and Pharmacology, Michael Okpara University of Agriculture, Umudike, Nigeria.

2-[(Diphenylmethyl) sulfinyl] acetamide (modafinil), is a wake-promoting agent use for treatment of excessive daytime sleepiness in narcolepsy. Molecular mechanics studies of 2-[(diphenylmethyl) sulfinyl] acetamide (modafinil) was performed according to the Hartree-Fock (HF) calculation method by Argus Lab 4.0.1 software. The molecular mechanics potential energy function were evaluated in terms of energies associated with bonded interactions (bond length, bond angle and dihedral angle) as well as non-bonded interactions (Vander Waals and electrostatic). Surfaces were created to visualize excited state properties such as highest occupied molecular orbital’s, lowest unoccupied molecular orbital’s and electrostatic potential (ESP) mapped density. The minimum potential energy was calculated by geometry convergence function by Argus Lab software. The most feasible position for the drug to interact with the receptor was found to be -108.034930 au (-67793.003600 kcal/mol). These results could help us in understating the drug-receptor interactions.

Modafinil, Molecular Mechanics, Arguslab Software, Molecular Mechanics

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