QUANTUM MECHANICAL CALCULATIONS OF IR SPECTRA; REACTION ENERGIES OF C-O (R-O) THERMAL BOND RUPTURE FOR CEFUROXIME PRODRUGS

Abstract

PM3 calculations were carried out for the estimation vibration frequencies, IR absorption intensities, normal coordinates and some physical properties as heat of formation, dipole moment, and ΔEHOMO-LUMO ---etc. for Cefuroxime prodrugs at its calculated equilibrium geometries. Assignment of the vibrations was done depending on the picture of their modes obtained from Gaussian-03 program. Also reaction path for the breakage of the (R-O) C-O bond for all of the derivatives were calculated (in the gas phase). Comparisons were done between the total energies of their reactants, products, activation energies and transition states. The results show impossible use for some substituted organic groups as prodrugs for acidic Cefuroxime drug, whereas others show possible use as prodrugs on breakage the (R-O) C-O bond.