Multispectroscopic analysis, atomic force microscopy, molecular docking and molecular dynamic simulation studies of the interaction between [SnMe2Cl2(Me2phen)] complex and ct-DNA in the presence of glucose

In this study, the spectroscopic methods (UV-vis, fluorimetric), Atomic force microscopy, and computational studies (molecular docking and molecular dynamic simulation) were used to investigate the interaction of [SnMe₂Cl₂(Me₂phen)] complex with CT-DNA in the presence of glucose. The results showed the complex in the medium containing glucose has less effect on calf thymus DNA (ct-DNA) than the medium without glucose. Cytotoxicity of [SnMe₂Cl₂(Me₂phen)] complex on MCF-7 cells was examined and showed Sn(IV) complex possesses potential cytotoxicity against this cell line. Molecular docking study showed that Sn(IV) complex interacts with DNA by groove binding mode. Radius of gyration (Rg) was smaller upon binding of the Sn(IV) complex suggesting a more compact structure of DNA in the presence of Sn(IV) complex.Communicated by Ramaswamy H. Sarma.

Studies on the Interaction of [SnMe2Cl2(bu2bpy)] Complex with ct-DNA Using Multispectroscopic, Atomic Force Microscopy (AFM) and Molecular Docking

The interaction of SnMe₂Cl₂(bu₂bpy)complex with calf thymus DNA (ct-DNA) has been explored following, using spectroscopic methods, viscosity measurements, Atomic force microscopy, Thermal denaturation and Molecular docking. It was found that Sn(IV) complex could bind with DNA via intercalation mode as evidenced by hyperchromism and bathochromic in UV-Vis spectrum; these spectral characteristics suggest that the Sn(IV) complex interacts with DNA most likely through a mode that involves a stacking interaction between the aromatic chromophore and the base pairs of DNA. In addition, the fluorescence emission spectra of intercalated methylene blue (MB) with increasing concentrations of SnMe₂Cl₂(bu₂bpy) represented a significant increase of MB intensity as to release MB from MB-DNA system. Positive values of ΔH and ΔS imply that the complex is bound to ct-DNA mainly via the hydrophobic attraction. Large complexes contain the DNA chains with an average size of 859 nm were observed by using AFM for Sn(IV) Complex-DNA. The Fourier transform infrared study showed a major interaction of Sn(IV) complex with G-C and A-T base pairs and a minor perturbation of the backbone PO₂ group. Addition of the Sn(IV)complex results in a noticeable rise in the Tm of DNA. In addition, the results of viscosity measurements suggest that SnMe₂Cl₂(bu₂bpy) complex may bind with the classical intercalative mode. From spectroscopic and hydrodynamic studies, it has been found that Sn(IV)complex interacts with DNA by intercalation mode. Optimized docked model of DNA-complex mixture confirmed the experimental results.

Design of coordination polymers with 4′-substituted functionalized terpyridyls in the backbone and pendent cyclopentadienyliron moieties

Synthesis and characterization of coordination polymers containing 4′-substituted functionalized terpyridines and cyclopentadienyliron moieties.

Pt−Me bond cleavage in the reactions of dimethylplatinum(II) complexes containing chelating phosphine ligands with organotin(IV) chlorides

Selective Pt−Me bond activation of dimethylplatinum(II) complexes [PtMe2(PP)] (PP = dppm (bis(diphenylphosphino)methane), dppe (1,2-bis(diphenylphosphino)ethane), dppp (1,3-bis(diphenylphosphino)propane)) was achieved by SnMe2Cl2 to yield the corresponding platinum(II) complexes [PtMeCl(PP)] (PP = dppm, dppe, dppp) and cis-[PtCl2(PP)] (PP = dppm, dppp). On the other hand, the reactions of complexes [PtMe2(PP)] (PP = dppm, dppe, dppp) with SnPh3Cl resulted in the selective cleavage of the Pt−Me bond to afford the methylplatinum(II) complexes [PtMeCl(PP)]. Notably, the reaction of [PtMe2(dppm)] with SnMe2Cl2 and SnPh3Cl also gave the ionic A-frame complex [Pt2Me2(μ-Cl)(μ-dppm)2]Cl. The variable-temperature 1H and 31P NMR spectroscopy shows that the cleavage of the Pt−Me bond occurs very rapidly and the short-lived platinum(IV) intermediate is difficult to detect during the reaction. An explanation is presented on the basis of the nature of the strong π-acceptance of the phosphine ligand, which resulted in the formation of a very unstable platinum(IV) intermediate.

Tetra-chlorido-(1,10-phenanthroline-κN,N')tin(IV) 1,2-dichloro-ethane hemisolvate

The asymmetric unit of the title compound, [SnCl₄(C₁₂H₈N₂)]·0.5C₂H₄Cl₂, contains a tin complex and one disordered half-mol­ecule of the solvent dichloro­ethane [occupancies 0.71 (2):0.29 (2)]. The six coordinate Sn(IV) atom adopts a distorted octa­hedral geometry. π–π inter­actions between adjacent aromatic rings [interplanar distance 3.483 (5) Å] seem to be effective in the stabilization of the crystal packing.

Oxidative addition of n-alkyl halides to diimine-dialkylplatinum(II) complexes: a closer look at the kinetic behaviors

The n-alkyl halides, RX, were oxidatively added to the platina(II)cyclopentane complexes [Pt[(CH2)4](NN)], in which NN = bpy (2,2'-bipyridyl) or phen (1,10-phenanthroline), to give the platinum(IV) complexes [PtRX[(CH2)4](NN)], R = Et and X = Br or I; R = nBu and X = I, 1-3. The same reactions with the analogous dimethyl complex [PtMe2(bpy)] gave the expected platinum(IV) complexes [PtRXMe2(bpy)], R = Et or nPr and X = Br or I; R = nBu and X = I, 4-8. Kinetics of the reactions in benzene and acetone was studied using UV-vis spectrophotometery and a common S(N)2 mechanism was suggested for each case. The platina(ii)cyclopentane complexes reacted faster than the corresponding dimethyl analogs by a factor of 2-3. This is described as being due to a lower positive charge, calculated by density functional theory (DFT), on the platinum atom of [Pt[(CH)2)4](bpy)] compared with that on the platinum atom of the dimethyl analog [PtMe2(bpy)]. The values of DeltaDeltaS(double dagger) = DeltaS(double dagger)(acetone) - DeltaS(double dagger)(benzene) were found to be either positive or negative in different reactions and this is related to the solvation of the corresponding alkyl halide. It is suggested that in these reactions of RX reagents, for a given X, the electronic effects of the R group are mainly responsible for the change in the rates of the reactions and the bulkiness of the group is far less important.