Abstract

COMPUTATIONAL STUDY ON THE ELECTRONIC STRUCTURE OF BENZYLPENICILLIN-LACTIM-ENOL ZWITTERIONS BY AUSTIN MODEL-1

Dasari Chandrasekhar Rao and Bojja Rajeshwar Rao*

ABSTRACT

The electronic structure and conformations on zwitterions of benzylpenicillin- lactim-enol have been optimized and calculated by semi-empirical molecular orbital Austin Model-1 (AM1) method. It includes experimental parameters and extensive simplification of the Schrodinger’s equation (HΨ=EΨ) for calculation of various properties in the gas phase, usually considering an isolated molecule surrounded by vacuum. The formation of zwitterions of benzylpenicillin lactim-enol has been studied by comparison of the different positions of net charges on nitrogen atoms in the molecule. In this connection, the heats of formation (ΔHfo), dipole moment (μ), full atomic charges and energies of frontier molecular orbitals (EHOMO and ELUMO) have been performed and discussed for their stabilities.

Keywords: benzylpenicillin-lactim-enol, HOMO, LUMO, zwitterions, induction effect.