Volume 40, Issue 5-6

Lead (Pb) is one of the most important heavy metals that possess many applications in different kinds of industrial procedures and consumer products. The adverse effects of Pb on different parts of the immune system have been reported in various studies. Although it has been shown that high concentrations of Pb have low cytotoxicity on human lymphocytes, the effects of non-cytotoxic concentrations of Pb (detected in human blood) on cellular organelles and oxidative stress factors of human lymphocytes have yet to be determined. In this study, human lymphocytes were obtained from the blood of healthy male volunteers through the use of the Ficoll standard method. The intention of this paper was to determine the effects of non-cytotoxic concentrations of Pb on human lymphocytes using the accelerated cytotoxicity mechanism screening technique. For determination of cell viability, lymphocytes were treated with 0–1 m m Pb for 12 h. Subsequently, we assayed the effects of non-cytotoxic concentrations of Pb which are detected in human blood on human lymphocytes and investigated if Pb can affect oxidative stress and cellular organelles at these concentrations. So, in concentrations which have no cytotoxic effects, Pb is shown to induce oxidative stress in addition to inflicting damage on mitochondria and lysosomes in human blood lymphocytes.

The reaction of dimethyl tin(IV) dichloride with 1,2-diphenylethane-1,2-dione dihydrazone in the presence of metal ions in a 2:2:1 molar ratio resulted in the isolation of macrocyclic complexes of the types [MLX 2 Sn(CH 3 ) 2 ] and [CuLSn(CH 3 ) 2 ]X 2 (M=Mn(II), Co(II), Ni(II) and Zn(II); X=Cl or NO 3 ). In both the cases, complexes exhibit identical patterns suggesting them to be isostructural. The cyclization has been identified on the basis of IR, 1 H NMR and 119 Sn NMR studies, and the overall geometry of the complexes has been assigned by the data obtained from elemental analyses, electron paramagnetic resonance and electronic spectral studies, and conductivity and magnetic susceptibility measurements. Except for the complexes of copper, which are square planar, all other complexes have octahedral structures. All the synthesized tin(IV) macrocyclic metal complexes were tested for their in vitro anti-fungal activity against some fungal strains, namely Aspergillus fumigatus and Trichoderma harzianum .

To prepare a new tin(IV) complex ( 1 ), [(SnMe 2 ) 2 (C 15 H 9 O 2 )(OCH 2 CH 3 )(O)] 2 , with strong optical absorption, anthracene-9-carboxylic acid (HL) with a large conjugated π-system and rich optical properties has been used as a ligand. The characterization of title complex was performed by various spectroscopic methods, including 1 H NMR, 13 C NMR, 119 Sn NMR, UV, IR, and elemental analyses (CHN). The crystal structure of complex 1 was determined by single-crystal X-ray diffraction. The results of spectroscopic data along with structural analyses showed that complex 1 is a tetranuclear, centrosymmetric dimeric and contains two Sn atoms, one in a five-coordinate environment and the other in a six-coordinate environment. Thermogravimetric and differential thermal analyses (TGA and DTA) have been used to study the thermal behavior of 1 . The investigation of photoluminescence properties and thermal behavior of complex 1 showed that this compound has the necessary conditions for its use as a precursor in the manufacture of optical devices. This compound was used as an emitting layer for the preparation of an organic light-emitting diode. The effect of the complex concentration on the electrical properties of the diode was investigated.

Here, we report a family of polyhedral oligomeric silsesquioxanes with eight branches of 3-aminopropyltriethoxysilane tethered to nano-colloidal silica, which is characterized by 1 H nuclear magnetic resonance spectroscopy, elemental analysis (CHN analysis), dynamic light scattering, scanning electron microscopy, energy-dispersive spectroscopy and thermogravimetric analysis. Furthermore, a clean, efficient, straightforward one-pot multicomponent synthetic method for the synthesis of propargylamines in good yields has been devised using nano-colloidal silica-tethered polyhedral oligomeric silsesquioxanes with eight branches of 3-aminopropyltriethoxysilane as superior catalyst under microwave irradiation.

The reaction of N , N , N′ , N′ -tetramethyl guanidine, NHC(N(CH 3 ) 2 ) 2 (TMGD) and CdBr 2 ·4H 2 O in ethanol led to the formation of [TMGDH][CdBr 3 ] ( 1 ), which crystallizes in the monoclinic space group C c with Z =4, a =8.9079(7) Å, b =18.5810(14) Å, c =8.1637(6) Å, β =107.953(3)°, and V =1285.44(17) Å 3 . In the crystal lattice, 1 is organized in one-dimensional anionic chains of CdBr 4 tetrahedra sharing two corners. To our knowledge, this is the first evidence of such a coordination geometry described for a bromocadmate derivative. The negative charges are compensated by monoprotonated N , N , N ′, N ′-tetramethyl guanidinium cations (TMGDHs), which are in N-H hydrogen bonding interaction with the terminal bromide atoms of the anionic chain. The title compound was also characterized by middle and far-infrared spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The elemental analysis corroborates as well the X-ray elucidation. Multinuclear solution nuclear magnetic resonance (NMR) spectroscopic measurements ( 1 H, 13 C{ 1 H}) were conducted in D 2 O.