Abstract

STUDY OF THE ELECTRONIC STRUCTURE AND CONFORMATIONAL ANALYSES ON ZWITTERIONS OF BENZYLPENICILLIN ENOL TAUTOMER BY AM1 METHOD

Bojja Rajeshwar Rao* and Dasari Chandrasekhar Rao

Abstract

The electronic structure and conformations on zwitterions of benzylpenicillin enol tautomer have been optimized and calculated in the gas phase by semi-empirical molecular orbital AM1 method usually considering an isolated molecule surrounded by vacuum. The formation of zwitterions of benzylpenicillin enol tautomer 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 (ΔHf o), dipole moment (μ), full atomic charges and energies of frontier molecular orbitals (EHOMO and ELUMO) have been performed and discussed. The effect of conformational changes and their stabilities have been determined.

Keywords: Benzylpenicillin enol tautomer, AM1, zwitterions, induction effect, frontier molecular orbital.