Volume 4, Issue 3

17-Thienyl-and 17-benzo[b]thienyl-3-hydroxyestra-1,3,5(10),16-tetraenes were synthesized by either sequential or one-pot Suzuki cross-coupling and Wittig olefination reactions. At 160 °C, heteroaryl substituted steroids were observed to undergo thermal intramolecular cyclization to produce E-ring heteroareno-annelated estranes.

The Wittig reaction of carbaldehydes with alkoxycarbonylhalomethylidenetriphenylphosphoranes can be performed with ease in solventless systems. The analogous reaction of carbaldehydes with acylhalomethylidenetriphenylphosphoranes requires a small amount of solvent, such as chloroform, in order for the reaction to proceed. The products of the reaction are versatile precursors for further transformations, such as the Suzuki-Miyaura cross-coupling reaction.

Antifungal activity of organic compounds (aromatic, salicylic derivatives, cinnamyl derivatives etc) on Fusarium Rosium (14 compounds) and Aspergillus niger (17 compounds) was studied and QSAR models were developed relating molecular descriptors with the observed activity. Back propagation Neural Network models and single and multiple regression models were tested for predicting the observed activity. The data fit as well as the predictive capability of the neural network models were satisfactory (R2 = 0.84, q2 = 0.73 for Fusarium Rosium and R2 = 0.75, q2 = 0.62 for Aspergillus niger). The descriptors used in the network for the former were X4 (connectivity) and Jhetv (topological); and TIC1 (information) and SPI (topological) for the latter fungus. Antifungal activities of these organic compounds were generally lower against the latter than with the former fungus.

Cu (II) complexes with the sterically hindered diphenol derivatives 3,5-di(tert-butyl)-1,2-benzenediol (I), 4,6-di(tert-butyl)-1,2,3-benzenetriol (II) and the sulfur-containing 4,6-di(tert-butyl)-3-(2-hydroxyethylsulfanyl)-1,2-benzenediol (III) and 2-[4,6-di(tert-butyl)-2,3-dihydroxyphenylsulfanyl]acetic acid (IV) have been synthesized and characterized by elemental analysis, TG/DTA, FT-IR, ESR, XPS, XPD and conductivity measurements. Compounds I–III can coordinate in their singly deprotonated forms and act as bidentate ligands. These compounds yield Cu (II) complexes of the stoichiometry Cu(L)2, which have square planar geometry (g| > g⊥ > ge). Unlike them, compound IV behaves as a terdentate ligand, and its complex Cu(LIV)2 has distorted octahedral geometry. According to ESR data, only the Cu(LII)2 complex contains a very small amount of phenoxyl radicals. Antimicrobial activities of these ligands and their respective Cu (II) complexes have been determined with respect to Gram-positive and Gram-negative bacteria, as well as on yeasts. Their phytotoxic properties against Chlorella vulgaris 157 were also examined.

The crystal structures of six novel salts of 4-nitrobenzoic acid — namely, 2-hydroxyethylammonium 4-nitrobenzoate (I), 2-hydroxypropylammonium 4-nitrobenzoate (II), 1-(hydroxymethyl)propylammonium 4-nitrobenzoate (III), 3-hydroxypropylammonium 4-nitrobenzoate (IV), bis-(2-hydroxyethylammonium) 4-nitrobenzoate (V), morpholinium 4-nitrobenzoate (VI) — containing the same anion but different cations have been studied. The ionic forms of I-VI serve as building blocks of the supramolecular architecture, and in crystals they are held together via ionic N-H···O and O-H···O hydrogen bonds. In the crystal packing the building blocks of I-III are self-assembled via N-H...O, O-H···O and C-H...O hydrogen bonds to form the chains which are further consolidated into two-dimensional layers by the same type of interactions. In IV-VI the chain-like structures have been generated by building blocks.

Partially nanowire-structured TiO2 was prepared by a hydrothermal processing followed by calcination in air. The hydrogen titanate powder as-synthesized was calcined at 300 °C for 4 h to obtain the partially nanowire-structured TiO2. A dye-sensitized solar cell (DSC) with a film thickness of 5.6 μm, fabricated using the partially nanowire-structured TiO2 showed better performance than using a fully nanowire-structured TiO2 or a conventional equi-axed TiO2 nanopowder. The short-circuit current density (JSC), the open-circuit voltage (VOC), the fill factor (FF) and the overall efficiency (η) are 11.9 mA/cm2, 0.754 V, 0.673 and 6.01 %, respectively. The effects of one-dimensional nanostructure and electron expressway concept are discussed.

The surface pressure versus molecular area isotherms of some carotenoids: β,β-carotene-4-one (echinenone, ECH), β,β-carotene-4,4′-dione (canthaxanthin, CAN) and 4,4′-diapo-ω,ω-carotene-4,4′-dial (APO), spread at the air/water interface, are reported. A van der Waals type state equation is used to describe the high molecular area portions of the compression isotherms and interaction parameters within monolayers are derived. Quantum chemical semi-empirical SCF MO calculations (AM1 and PM3) are performed for the optimized geometries of molecules and dipole moments are calculated. Similar theoretical magnitudes are obtained by both methods. Surface properties, like collapse pressure, surface compressional modulus and interaction parameters are discussed in terms of dipole-dipole interactions, and correlations with the calculated quantities for the carotenoid molecules are analyzed. The orientation of the different carotenoid molecules in the monolayer is discussed.

The new homodinuclear complexes 1–4 of the type [LMII 2Cl2], heterotrinuclear complexes 5 and 6 of the type [LMII 2SnIVCl6] where M = CuII, MnII, CoII, NiII and CuII and NiII, respectively have been synthesized and characterized by elemental analysis and various spectroscopic techniques. The homodinuclear complexes possess two different environments (N2 and N2O2donor sets) for holding the metal ions. The metal ion in N2 set exhibits square planar geometry with two chloride ions in the inner sphere but rhombic structure is found in tetradentate N2O2 Schiff base cavity while in heterotrinuclear complexes SnIV atom is in the octahedral environment. The interaction of complexes 1 and 5 with calf thymus DNA was carried out by absorption spectroscopy and cyclic voltammetry. The intrinsic binding constants (K b) of complex 1 and 5 were determined as 3.2 × 103 M−1 and 9.6 × 103 M−1, respectively suggesting that complex 5 binds more strongly to CT-DNA than complex 1. Fluorescence studies along with viscosity measurements have also been checked to authenticate the binding of metal complexes with DNA.

This work shows the modification of barbituric acid (BA) chemical shifts by dimethylsulphoxide (DMSO) molecules. The discussed changes are caused by creation of the H-bonded associates formed by barbituric acid with DMSO in solution. Free molecule of barbituric acid, the cluster of BA with two DMSO molecules and two different clusters of BA with four DMSO units are taken into consideration. The chemical shifts of these systems have been calculated and the obtained results have been compared with experimental data. Theoretical calculations predict a significant downfield shift for imino protons of barbituric acid involved in intermolecular-N-H...DMSO hydrogen bonds. The influence of the solvent molecules on other nuclei chemical shifts, especially protons of barbituric acid methylene group, is also reported. The calculations have involved Hartree-Fock and several Density Functional Theory methods. All methods correctly describe experimental 1H and 13C NMR spectra of barbituric acid. The best consistence between experiment and theory is observed for the BLYP functional. Four approximations of magnetic properties calculations embedded in the Gaussian’98 package have been tested. The results of the performed calculations indicate that from a practical point of view the GIAO method should be preferred.

Linear-dichroic infrared spectra (IR-LD) of 3-ethoxy-4-(N-norcodeino-)cyclobutene-1,2-dione (1) and codeine dihydrogenphosphate (Codeinum phosphoricum) (2), oriented as solid suspensions in nematic liquid crystals, have been measured. IR characteristic band assignments were made, and used in stereo-structural predictions. The results were compared with crystallographic structures of similar organic systems, and found to be in good agreement.

The sustainable development rule implementation is tested by the application of chemometrics in the field of environmental pollution. A data set consisting of Cd, Pb, Cr, Zn, Cu, Mn, Ni, and Fe content in bottom sediment samples collected in the Odra River (Germany/Poland) is treated using cluster analysis (CA), principal component analysis (PCA), and source apportionment techniques. Cluster analysis clearly shows that pollution on the German bank is higher than on the Polish bank. Two latent factors extracted by PCA explain over 88 % of the total variance of the system, allowing identification of the dominant “semi-natural” and “anthropogenic” pollution sources in the river ecosystem. The complexity of the system is proved by MLR analysis of the absolute principal component scores (APCS). The apportioning clearly shows that Cd, Pb, Cr, Zn and Cu participate in an “anthropogenic” source profile, whereas Fe and Mn are “semi-natural”. Multiple regression analysis indicates that for particular elements not described by the model, the amounts vary from 4.2 % (Mn) to 13.1 % (Cr). The element Ni participates to some extent to each source and, in this way, is neither pure “semi-natural” nor pure “anthropogenic”. Apportioning indicates that the whole heavy metal pollution in the investigated river reach is 12510.45 mg·kg−1. The contribution of pollutants originating from “anthropogenic sources” is 9.04 % and from “semi-natural” sources is 86.53 %.