Aryltelluronic Triorganotin(iv) Esters: Syntheses, Structural Characterizations And Biological Activity Research

Organotin compounds have been concerned much due to their key diversity andextensive application. At present, Synthesis of new high efficiency, low toxicityanti-cancer activity of organotin compounds has become a hot field of organotinchemistry research. Owing totheir vacant dorbits, Sn atoms can accept foreignelectronics for coordination, which can form compounds of high stability. The oxygenatoms of tellurium acids are good electron donors that can bond with tin atoms, besidesorganic tellurium compounds have high biological activity as well as good protection onthe organism. Given the above conditions, we synthesized aryltelluronic organotincomplexes and embarked on an investigation of these organotin devatives. The mainwork are as follows:1. Four new μ2-oxo-bridged dinuclear aryltelluronic triorganotin esters [ArTe(μ-O)(OH)(OSnR3)2]2(Ar=n-propyl-Ph, R=Me:1, R=Ph:2; Ar=i-propyl-Ph,R=Me:3, R=Ph:4) were designed and synthesized by the reaction ofμ2-oxo-bridged dinuclear aryltelluronic acids and the corresponding R3SnCl (R=Me,Ph) with potassium hydroxide in methanol. All the complexes were characterized byX-ray crystallography, elemental analysis, FT-IR, and NMR (1H,13C,119Sn)spectroscopy. Results showed that telluronic acid, potassium hydroxide and triorganotinchloride R3SnCl in1:6:4ratios in methanol solution, while only a4OSnR3coordinatedproduct was got with one residual coordination action of the hydroxide ligands. Thegeometry of the tellurium atom is described as a distorted octahedron, and each tin atomis best described as a distorted tetrahedron.2. Six new μ2-oxo-bridged dinuclear aryltelluronic triorganotin esters [ArTe(μ2-O)(OSnR2Cl)(μ3-O)(OSnR2OH2CH3)]2(Ar=3,4-Dimethy-Ph, R=Me:5; Ar=3,5-Dimethy-Ph, R=Me:8),[ArTe(μ2-O)(OH)(OSnR3)2]2(Ar=3,4-Dimethy-Ph, R=Me:6, R=Ph:7；Ar=3,5-Dimethy-Ph, R=Me:9, R=Ph:10) were designed, synthesized and characterization by the reaction of μ2-oxo-bridgeddinuclear aryltelluronicacids and the corresponding R2SnCl2(R=Me), R3SnCl (R= Me, Ph) with potassium hydroxide in methanol. Results indicate that telluronic acid,potassium hydroxide and diorganotin chloride R2SnCl2in1:6:4ratios in methanolsolution, while all OSnR3coordinated product was got. The structural analysis indicatesthat there exists a highly centrosymmetric8-member macrocyle containing Sn2Te2O4dipping until it is perpendicular to the almost planar four-membered Te2O2core. Thegeometry of the tellurium atom is described as a distorted octahedron, and tinatom arebest described as distorted tetrahedron and distorted trigonal bipyramid. Thosearyltelluronic triorganotin esters are similar with the structures described above.3. Six new μ2-oxo-bridged dinuclear aryltelluronic triorganotin esters [ArTe(μ-O)(OH)(OSnR3)2]2(Ar=o-methyl-Ph, R=Me:11, R=Ph:12; Ar=m-methyl-Ph, R=Me:13, R=Ph:14; Ar=p-methyl-Ph, R=Me:15, R=Ph:16;) were designed, synthesized and characterization by the reaction ofμ2-oxo-bridgeddinuclear aryltelluronic acids and the corresponding R3SnCl (R=Me,Ph) with potassium hydroxide in methanol including four obtained by X-ray singlecrystal diffraction test. Results show that their triorganotin chloride product structureare similar with those described before.4. Antitumor activities in vitro of all crystal compounds were tested, which showthat the majority of these complexes showed significant antitumor activity againsthuman lung a denocarcinma cell line(A549) and hepatoma carcinoma cell line(HepG2).We make a summing up of structure-activity relationship. For example, the antitumoractivity of the organotin derivatives decreases in the order triphenyltin> dimethyltin>trimethyltin introduction of substituents to o-position and p-position have relativelysignificant synergies.5. The interaction between aryltelluronic organotin esters with bovine serumalbumin (BSA) had been studied by fluorescence spectrometry. Experimental resultsshowed that the intrinsic fluorescence of BSA was quenched by majority of thesecomplexes, while the intrinsic fluorescence of BSA was strengthen by minority of thesecomplexes. We studied the characteristics of the fluorescence quench spectroscopybetween aryltelluronic organotin esters with BSA and the result is dynamic quenching.According to the Stern-Volmer equation, we calculate the quenching constants, which reflects the concentration-response relationship between biological macromoleculesand fluorescence quenching agent molecular when they diffusion and collide with eachother to reach the dynamic equilibrium. And then calculate the constant of combinationand the binding points, so that we can conclude that the binding sites of fluorescencequenching agent molecules and BSA in amount of substance ratio1:1, which show thatstrong binding between these complexes with BSA when were storaged and transportedby protein. It is certain forward-looking for further research on biological andpharmacological properties.