Synthetic Stratagem, Characterization and Potential Applications of Main group/Heteronuclear Transition Metal Complexes derived from N, 0 containing Ligands

Abstract

This dissertation compnses two parts; the first deals with the synthesis of heteroleptic triorganobismuth(V) carboxylate whereas the second pertains to the preparation of heterodi- and trinuclear 3d/4f complexes derived from bi-compartmental ligands. A senes of heteroleptic triorganobismuth(V) carboxylates (1-25) of general formula Ar3Bi(COOR)2; where Ar = C6Hs (1-12), p-CH3C6H4 (13-25) was synthesized by stoichiometric reaction between the precursor, Ar3BiBr2, and the respective carboxylic acid in dry toluene. The synthesized compounds were characterized by FT-IR, NMR spectroscopy and single crystal X-ray technique to get unequivocal evidence for their structural motifs. The XRD data for (7, 17 & 18) depict the existence of five-coordinated bismuth center having distorted trigonal bipyramidal molecular geometry, whereas (19) described weakly hexacoordinated bismuth including a unique bidentate interaction of one of the carboxylate ligands, assuming a distorted octahedral molecular geometry. The molecular docking studies demonstrate that compounds (5, 7 & 20) give significant GOLD (Genetic optimization for ligand docking) fitness scores of 60.09, 56.30 and 62.65 against epidermal growth factor receptor tyrosine kinase, H pylori urease and human pancreatic alpha amylase, respectively. The antibacterial activity profile looks good with MIC value range from 50 to 6.25 flg/mL against various bacterial and fungal strains and the values are comparable to the reference drug(s). The compounds (2 & 14) display significant % alpha amylase inhibition of around 62.3%, whereas (7) exhibits 30 mm bald zone of inhibition for alpha amylase and protein kinase inhibition studies, thus, proving their worth as moderate enzyme inhibitors. The second part of the dissertation involves the formation of transition metal complexes. The heterodi- and trinuclear complexes of general formula [(Ml)n(H20)(L)nM2(N03)n] (26-45) were synthesized by reacting bi-compartmental ligands with the specific 3d metal (Zn) and various 4f metals (La, Nd, Sm, Gd and Dy).