Understanding bio-activity of salicylaldehyde related complexes

• Main Author: Yee, Alven Yi Long.
• Other Authors: Lim Kok Hwa
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Science::Biological sciences::Biochemistry
• Online Access: http://hdl.handle.net/10356/38863
• Institution: Nanyang Technological University

The structural optimizations of a series of salicylaldehyde semicarbazone (H2ssc)and their Cu(II) and Au(II) complexes of have been carried out using Density Functional Theory (DFT) calculations and their structural parameters comparatively analyzed. H2ssc and its complexes have been shown to exhibit tumour inhibitory activity with the metal complex of such ligands to display enhanced biological activities. Therefore a molecular understanding of metal-base therapeutic drugs has become of particular interest in bio-activity predictions for the purpose of drug design. In this project, the optimized structures from DFT calculations show that the metal atom is four coordinated with a distorted square planar geometry with a N-O2-Cl donor set.Conformations studies have been conducted to ensure that the optimized structures are not local but global minima on the potential energy surface. A global minimum on the potential energy surface is equivalent to the most stable conformation. The reaction energies of the compounds for he complexation process have also been computed which indicate that for the complexation, process with Cu(II) is xothermic and spontaneous but otherwise for Au(II). The electronic properties have also been extensive studied using Natural Bond Orbital (NBO) analysis and Bader charge analysis. In addition, the ionization otential and chemical hardness of the ompounds have also been investigated using Koopman’s theorem. However, it was noted that the effect of substituent on these molecular properties was insignificant.