Wall Lerche (suedewarm0)

A novel three-dimensional (3D) ZnII coordination polymer, namely, poly[[[1,4-bis(pyridin-4-yl)benzene](μ3-3,3'-[1,3-phenylenebis(methylene)]bis(oxy)dibenzoato)zinc(II)] 1,4-bis(pyridin-4-yl)benzene], [Zn(C22H16O6)(C16H12N2)]·C16H12N2n or [Zn(PMBD)(DPB)]·DPBn, 1, where H2PMBD is 3,3'-[1,3-phenylenebis(methylene)]bis(oxy)dibenzoic acid and DPB is 1,4-bis(pyridin-4-yl)benzene, has been synthesized by self-assembly using zinc nitrate, a semi-rigid dicarboxylic acid and a nitrogen-containing ligand. The single-crystal X-ray structure determination indicates that 1 possesses an intriguing 3D architecture with a 4-connected uninodal cds topology, which is constructed from dinuclear Zn2 clusters and V-shaped PMBD2- linkers. Compound 1 exhibits excellent photocatalytic activity on the degradation of the organic dyes Rhodamine B (RhB), Rhodamine 6G (Rh6G) and Methyl Red (MR).Fluorine substitutions on the furanose ring of nucleosides are known to strongly influence the conformational properties of oligonucleotides. In order to assess the effect of fluorine on the conformation of 3'-deoxy-3'-fluoro-5-methyluridine (RTF), C10H13FN2O5, we studied its stereochemistry in the crystalline state using X-ray crystallography. The compound crystallizes in the chiral orthorhombic space group P212121 and contains two symmetry-independent molecules (A and B) in the asymmetric unit. The furanose ring in molecules A and B adopts conformations between envelope (2E, 2'-endo, P = 162°) and twisted (2T3, 2'-endo and 3'exo, P = 180°), with pseudorotation phase angles (P) of 164.3 and 170.2°, respectively. The maximum puckering amplitudes, νmax, for molecules A and B are 38.8 and 36.1°, respectively. In contrast, for 5-methyluridine (RTOH), the value of P is 21.2°, which is between the 3E (3'-endo, P = 18.0°) and 3T4 (3'-endo and 4'-exo, P = 36°) conformations. The value of νmax for RTOH is 41.29°. Molecules A and B of RTF generate respective helical assemblies across the crystallographic 21-screw axis through classical N-H...O aand O-H...O hydrogen bonds supplemented by C-H...O contacts. Adjacent parallel helices of both molecules are linked to each other via O-H...O and O...π interactions.Recently, fluorenylmethoxycarbonyl (Fmoc) amino acids (e.g. Fmoc-tyrosine or Fmoc-phenylalanine) have attracted growing interest in biomedical research and industry, with special emphasis directed towards the design and development of novel effective hydrogelators, biomaterials or therapeutics. With this in mind, a systematic knowledge of the structural and supramolecular features in recognition of those properties is essential. This work is the first comprehensive summary of noncovalent interactions combined with a library of supramolecular synthon patterns in all crystal structures of amino acids with the Fmoc moiety reported so far. Moreover, a new Fmoc-protected amino acid, namely, 2-[(9H-fluoren-9-ylmethoxy)carbonyl](methyl)amino-3-4-[(2-hydroxypropan-2-yl)oxy]phenylpropanoic acid or N-fluorenylmethoxycarbonyl-O-tert-butyl-N-methyltyrosine, Fmoc-N-Me-Tyr(t-Bu)-OH, C29H31NO5, was successfully synthesized and the structure of its unsolvated form was determined by single-crystal X-ray diffraction. The s the Long-Range Synthon Aufbau Modules, further supported by energy-framework calculations, are discussed. Furthermore, the relevance of Fmoc-based supramolecular hydrogen-bonding patterns in biocomplexes are emphasized, for the first time.The synthesis and characterization of two new 1,3,5-triazines containing 2-(aminomethyl)-1H-benzimidazole hydrochloride as a substituent are reported, namely, 2-[(4,6-dichloro-1,3,5-triazin-2-yl)amino]methyl-1H-benzimidazol-3-ium chloride, C11H9Cl2N6+·Cl- (1), and bis(2,2'-[(6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl)]bis(methylene)bis(1H-benzimidazol-3-ium)) tetrachloride heptahydrate, 2C19H18ClN92+·4Cl-·7H2O (2). Both salts were characterized using single-crystal X-ray diffraction analysis and IR spectroscopy.