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Abstract: Two novel l-lysinium hydrogensquarate monohydrate (1) and the corresponding salt of the l-lysinium dication (2) are synthesized and their structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy oriented colloid suspensions in nematic host, TGA, DSC, DTA methods, positive and negative HPLC tandem mass spectrometry (ESI-MS·MS). Quantum chemical methods are used to calculate the electronic structure, vibrational data and electronic spectra. Two novel structural motifs have been obtained, isolated [(HSq−)] and tetramolecular [(H2Sq)(HSq)2(Sq)]4− anion, respectively. Preliminary second harmonic generation measurements are also performed. [Copyright &y& Elsevier]

Abstract: This work describes the synthesis and characterization of two Pd(II) complexes [(3,5-Hdmpz)2Pd2(μ-3,5-dmpz)2(2,6-dipic)] (1) and [Na2(H2O)4Pd(2,6-dipic)2] (2) (3,5-Hdmpz=3,5-dimethylpyrazole and 2,6-dipic=2,6-pyridinedicarboxylate). The X-ray molecular structure determination shows that 1 is a binuclear complex bridged by two 3,5-dmpz units and is completely unsymmetric since one palladium atom contains two protonated 3,5-Hdmpz ligands and the other one contains the 2,6-dipic2− unit that coordinates in a bidentate fashion. The central six-member Pd2N4 core shows a boat-like conformation where the palladium atoms are positioned at the vertices of the boat. The molecules are assembled in an extended zigzag one-dimensional network formed through 3,5-Hdmpz-carboxylate (2,6-dipic2−) hydrogen bonds. The packing of complex 2 is constructed of cationic Na+–H2O and anionic Pd-2,6-dipic2− units joined together to form an extended two dimensional network. Alternate short and long Na–Na distances are observed in the cationic layer. A detailed quantum-chemical calculation on the Na-chains in 2 has been made. Complex 1 shows a luminescence property and antimicrobial activity against Bacillus subtilis, Escherichia coli and Aspergillus niger where the MIC has been found to be 100μg/mL for all three species. [Copyright &y& Elsevier]

Abstract: Two mononuclear Cu(II) complexes, [Cu(L1H2)](ClO4)1.25Cl0.75·1.25H2O (1) and [Cu(L2H2)](ClO4)2 (2), of the pyridoxal Schiff base ligands N,N′-dipyridoxylethylenediimine (L1H2) and N,N′-dipyridoxyl-1,3-propanediimine (L2H2) are reported. X-ray crystal structures of both complexes are also reported. In both complexes the pyridoxal nitrogen atoms remain protonated. In the solid state, the tetradentate Schiff base ligand is virtually planar in 1, while in 2 the ligand conformation is like an inverted umbrella. In cyclic voltammetry experiments it is found that in these complexes the Cu(III) and Cu(I) states are more easily accessible than in their salen type analogs. The pyridoxal Schiff base complexes are also found to be resistant to oxidative electro-polymerization, unlike their corresponding salicyl aldehyde Schiff base complexes. [Copyright &y& Elsevier]

Abstract: Novel molecular complexes of 1,10-phenanthroline (phen) and 5-amino-1,10-phenanthroline (5-NH2-phen) [(5-NH2-phen)2(phen) (H2O)3 (1), (phen)2(imidazole) (H+) (BF4 −) (2), (phen)2(benzimidazole) (H+) (BF4 −) (3), (5-NH2-phen)4(H2O)3 (4), and (phen)3 (indole) (H+) (BF4 −) (5)] were synthesized via self-assembly processes and their in vitro anticancer activity was investigated. The structures of the compounds were confirmed by UV, FTIR, CIMS(CH4) and elemental analysis. The crystal structure of 2 was determined by X-ray diffraction. Cytotoxicity of the substances was measured using the cultivated human tumour cell lines HepG2, HEp-2, and 8-MB-GA. The tested substances showed different activity depending on the cell line and amount used. Substances 2 and 3 were not toxic to the non-tumour cells (Lep-3), but significantly toxic to all tumour ones. This is not the case with compounds 4 and 5, which are non-toxic towards carcinogenic cell lines, but even stimulate both HepG2 and HEp-2. [Copyright &y& Elsevier]

Abstract: Mononuclear transition metal complexes of the polyether ionophorous antibiotic monensin (monensic acid, MonH) with nickel(II) and zinc(II) were prepared and characterized using single crystal X-ray diffraction and spectral methods. Monensin complexes crystallize as [Ni(Mon)2(H2O)2]·H2O·5MeCN (1) and [Zn(Mon)2(H2O)2]·H2O·4.5MeCN (2), respectively, in the monoclinic space group P21. Compounds 1 and 2 consist of two monoanionic monensic acid ligands (monensinates) bound in a bidentate coordination mode to the transition metal ion. The metal center is placed in an octahedral environment with monensin anions occupying the equatorial plane of complexes via oxygens of carboxylate and hydroxyl groups located at the both ends of ionophore molecule. The strongly folded antibiotic anions are supported by intramolecular H-bonds, most of them originating from the two aqua ligands attached to the metal(II) ions in axial positions and completing their 6-fold coordination. The bioactivity assay reveals that the presence of divalent metal ion in the monensin complexes influences the biological properties of the ligand and should be taken into account when discussing its mode of action. [Copyright &y& Elsevier]

Anions and cations of the title compound, C5H8N3+·C4HO4−, are connected by moderately strong intermolecular N—H...O hydrogen bonds into an infinite three-dimensional network. Hydrogen squarate anions form dimers through strong O—H...O interactions. [ABSTRACT FROM AUTHOR]

Cations of the title compound, 1-carbamoyl-2-(4-hydroxy­phen­yl)ethyl­ammonium chloride monohydrate, C9H13N2O2+·Cl−·H2O, are connected by inter­molecular N—H⋯O [N⋯O = 2.905 (3) Å] hydrogen bonds between the amide and 4-hydr­oxy functions into helical chains propagating along the [010] axis. The Cl− ions and water O atom participate in a complex pattern of hydrogen bonds to link these ribbons into a three-dimensional network. [ABSTRACT FROM AUTHOR]