Pharmaco Dynamic Activity Analysis and Structural Property Interpretation on Some Antibiotic Compounds

Abstract

viii newlineABSTRACT newlineThe compounds under investigation are of spectroscopic grade were used for newlinerecording the FT-IR, FT-Raman, NMR and UV-Visible spectra. The quantum newlinechemical computations were carried out using Gaussian 09 programs, both for HF newlineand DFT levels with different appropriate basis sets like the standard 6- newline31++G(d,p) and higher level 6-311++G(d,p)basis sets. The most stable geometry newlineof the compounds was determined by conformational analysis. The deformation of newlinestructure related to obtaining the particular properties is interpreted. The newlinefundamentals are assigned to different modes of vibrations, based on the expected newlinerange, literature values, intensity of the band, possibility of vibrations in the newlinecompound and group theory principles etc. The compositional activity of the newlinesubstitutions is determined by the active participation of absorption bands. The newlineFrontier molecular orbital analysis has been performed for studying the chemical newlinereaction path and the cause of the inducement of the pharmaceutical property. The newlineelectronic transitions on HOMO-LUMO energy levels were monitored and the newlinereason for the pharmaceutical property was interpreted by the impact of ligand newlinegroups on base compound. The change of chemical environment over C and H newlinecausing the chemical reactivity of the compound were investigated by calculating newline1H and 13C NMR isotropic shielding at GIAO method using B3LYP/6- newline311++G(d,p) method. Molecular electrostatic potential view of the molecules newlinewere constructed at the level of B3LYP/6-311+G(d,p) theory with optimized newlinegeometry. The electrophilic and nucleophilic orientation with respect to the newlinesubstitutional groups was elucidated. The elevated values of polarizabilities and newlinethe hyperpolarizabilities were calculated and the root cause of the drug activity newlinewas interpreted. The thermodynamic phase of the different compositional part of newlinethe compound was discussed and Gibbs free energy was calculated and the newlinecontinuity of the chemical reaction was monitored. The ECD and VCD spectra of newlinethe compound were simulated and the masking effect on toxicity was discussed in newlinedetail. The NBMO transitional process in various parts of the compound was newlineinvestigated and the high energy exchange among different species of the newlinecompound was keenly observed. newline