|Keywords (Extracted from title, table of contents and abstract of thesis)
organotin, organoantimony, carboxylates, germanium, triorganogermyl propionic acid, organotinoxides, triorganotin (iv) chloride, triarylantimony (v) dibromide, diorganotin, triorganotin
New organotin(IV) and organoantimony (V) compounds derived from the substituted triorganogermyl propionic acids of general formula ((R )3GeCH(R-)CH2COO)x_n M (R )n, [where M = Sn, Sb and, x = 4 for Sn and 5 for Sb. n = 2 for diorganotin (IV) derivatives in which RI = C6HS, R2 = CH3, n-C3H7, C6HS, R3 = CH3, C2HS, n-C4H9, C6HS, n-CgHI7, and n = 3 for triorganotin (IV) and triorganoantimony (V) compounds in which RI = C6HS, p-CH3C6~, R2 = CH3, n-C3H7, C6Hs, p-ClC6~, p-CH3C6~, o-CH30C6~, p-CH30C6~, R3 = H3, n-C4H9, C6Hs have been prepared Diorganotin (IV) derivatives have been synthesized by reaction of stoichiometric amounts of organotinoxides with triorganogermyl-substituted propionic acid at refluxed temperature of toluene. Water formed was continuously removed by the use of Dean and Stark apparatus. While the triorganotin (IV) and triorganoantimony (V) carboxylates were prepared by reaction of triorganotin (IV) chloride and triarylantimony (V) dibromide with triorganogermyl propionic acid in toluene in the presence of triethylamine.
These compounds were characterized by elemental analysis, IR, multinuclear NMR eH, I3c and 119Sn), mass spectrometry and in some cases X-ray crystallography. Spectroscopic data revealed that the diorganotin (IV) compounds have deformed octahedral or askew trapezoidal bipyramidal geometry in non-coordinated solvent. The triorganotin(IV) carboxylates are monomeric entities with tetrahedral geometry around tin atoms and organoantimonyCV) carboxylates are trigonalbipyramidal structure in noncoordinating solvent
In the solid phase, the situation is different. Infrared and crystallographic data show that diorganotin(IV) derivatives containing germanium have distorted octahedral geometry around tin atom and triorganotin(IV) derivatives have polymeric structure through bridging carboxylates ligands leading to R3Sn02 structure motif in which germanium atom adopts a distorted tetrahedral geometry. Similarly the triorganoantimony CV) derivatives containing germanium adopted trigonal bipyramidal geometry around antimony atom in solid state. While in some compounds coordination number of antimony atom increased to six, when the ligand acid behave as bidentate.
The fragmentation pattern and resulting fragment ions are in agreement with the proposed molecular structure and formulae of synthesized compounds.
The single X-ray crystal structures of the precursors, triorganogermyl substituted propionic acids (la\, Ia2, law and le?) and tricyclohexylantimony (V) dibromide have also been determined, in former the geometry of central four coordinated germanium atom is distorted tetrahedral while in later the molecule adopts a distorted trigonal bipyramidal geometry around antimony with bromine atoms occupy the axial position and three cyclohexyl rings at apical sites.
Biological screening of the selected synthesized compounds has shown the promising antibacterial, antifungal and insecticidal activity. These compounds were having good strength against the pathogens. The good activity of the compounds is probably due to the carboxylate ion, which acts as better carrier of organotin and organoantimony. The cytotoxicity of these compounds has also been determined by lethality bioassay protocol. The results revealed that the toxicity of organotin (IV) and organoantimony CV) derivatives have decreased considerably and their activity was further improved by incorporation of germanium in the carboxylate ligand.