Spectroscopic,structural, electrochemical,and cytotoxicity studies on dithiocarbamato-chelated ruthenium organometallics incorporating imine-phenol function

The heterogeneous phase reaction of [Ru(η²-RL)(PPh₃)₂(CO)Cl] (1) with the sodium salts of dimethyl dithiocarbamate (^MeDTC), diethyl dithiocarbamate (^EtDTC), and pyrrolidine dithiocarbamate (^PyrDTC) ligands led to the isolation of bright-yellow crystalline solids of type [Ru(η¹-RL)(PPh₃)₂(CO)(^R′DTC)] (2(R)(^R′DTC)) where η²-RL is C₆H₂O-2-CHNHC₆H₄R(p)-3-Me-5, η¹-RL is C₆H₂OH-2-CHNC₆H₄R(p)-3-Me-5, R is Me, OMe, Cl, and R^′ = Me, Et, Pyr. The binding of dithiocarbamate ligand is accompanied by the dissociation of Ru-O and Ru-Cl bonds along with concomitant prototropic shift from iminium–phenolato to imine–phenol motif. The reaction also involves a sterically controlled change in rotational conformation in going to the products. The X-ray crystal structure of [Ru(η¹-ClL)(PPh₃)₂(CO)(^EtDTC)] (2(Cl)(^EtDTC)) has been described here. An account of different spectral (UV–Vis, IR, NMR) and electrochemical data of the complexes are also asserted. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) analyses were performed to scrutinize the electronic structure and the absorption spectra of the complexes. One of the dithiocarbamato complexes has also been found to have in vitro antiproliferative properties against MDA-MB-231 breast cancer cell line which was determined by MTT assay. Cell death occurs mainly through apoptosis and flow cytometric analysis indicates that the complex induces cell cycle arrest in the sub G0/G1 phase.     

Green synthesis,characterization, and DFT calculations of diorganotin (IV) complexes of Schiff bases

Diorganotin (IV) complexes (1, 2, 3, 4), of the general formula R₂Sn(L)_m have been synthesized where R = n-But, n-Oct; m = 2 when L1 = N-[(Z)-(2-hydroxy-3-methoxybenzylidene)pyrazine-2-carboxamide and m = 1 when L2 = [3,4-bis-{[(E)-(2-hydroxy-3-methoxyphenyl) methylidene]amino}phenyl](phenyl)meth-anone. The prepared Schiff bases and diorganotin complexes have been characterized by elemental analysis, FTIR, and NMR (¹H, ¹³C, and ¹¹⁹Sn) spectroscopic studies. The molecular geometry, thermochemical values, and vibrational frequencies of two complexes in the ground state were calculated using the B3LYP density functional method with LANL2DZ basis set for Sn using Gaussian 09 software. A good correlation of theoretical and experimental results shows that in both the complexes the geometry around the central tin atom is tetrahedral. The studies were further extended to test and compare the in vitro cytotoxic activity of ligands and complexes against MCF-7 cell line by MTT assay. The IC50 values show that cytotoxic activity of ligands increased on complexation with tin metal.     

Nonsmooth ρ ? (η, θ)-invexity in multiobjective programming problems

In this paper we extend Reiland’s results for a nonlinear (single objective) optimization problem involving nonsmooth Lipschitz functions to a nonlinear multiobjective optimization problem (MP) for ρ − (η, θ)-invex functions. The generalized form of the Kuhn–Tucker optimality theorem and the duality results are established for (MP).     

Type-2 fuzzy linear system of equations with application in static problem of structures

In this paper, a new method is proposed to solve type-2 fuzzy linear system of equations by converting the system into three interval linear systems and one crisp linear system of equations. In this work, three possible cases of type-2 fuzzy linear system is considered depending upon uncertainty (as type-2 fuzzy number) in right-hand side vector $\tilde{B}$, in co-efficient matrix $\tilde{A}$, and both in co-efficient matrix $\tilde{A}$ as well as right-hand side vector $\tilde{B}$. Triangular perfect quasi type-2 fuzzy numbers are taken to propose the new method. The main significance of the proposed method is that it uses the arithmetic of interval theory, which makes this method easier to handle. Five numerical examples are solved to show the validation of the proposed technique. Further, two application problems related to 6-bar truss and rectangular sheet are encountered in type-2 fuzzy environment. Comparison among the results obtained by the present method and previously achieved results is also made in this work, which shows that the results are close enough and, in some cases, better bounds for the solution are obtained.