Acta Crystallographica Section EStructure Reports Online was launched in January 2001 as the IUCr's first electronic-only journal. It is a rapid communication journal for the publication of concise reports on inorganic, metal-organic and organic structures, and benefits from an enhanced electronic publication procedure. Each published report includes a set of key indicators, giving a summary of the main descriptors of the precision and completeness of the study, with indications of problems such as disorder. The publication...1-(2-Hydroxy-5-methylphenyl)ethanone (1H-indol-3-yl)acetylhydrazone- April 26, 2008 The indolyl NH group of the title Schiff base, C19H19N3O2, forms a hydrogen bond to the OH group of an inversion-related molecule, resulting in a hydrogen-bonded dimer; adjacent dimers are further linked through an interdimer NH...O hydrogen bond involving the C(=O)NHN=fragment to form a linear ribbon that runs along the a axis.http://scripts.iucr.org/cgi-bin/paper?bt2687 7-Ethoxy-4-methoxyisoflavone (monoethylformononetin)- April 23, 2008 The title compound, C18H16O4, is composed of a benzopyranone core with a 4-methoxyphenyl subsituent in the 3-position and an additional ethoxy group in the 7-position. The benzopyranone ring is not coplanar with the benzene ring, the dihedral angle between them being 41.76(7). The methoxy and ethoxy substituents are nearly coplanar with the ring systems to which they are attached. Individual molecules are linked by two kinds of intermolecular hydrogen bonds into chains containing classical...http://scripts.iucr.org/cgi-bin/paper?im2059 Tris2-(deuteriomethylsulfanyl)phenylphosphine deuteriochloroform 0.125-solvate- April 23, 2008 The title deuterated tripodal phosphine, C21H12D9PS30.125CDCl3, crystallizes as two independent molecules, one of which lies on a general position and the other about a threefold rotation axis, and as a deuteriochloroform solvate. The solvent molecule is disordered about a site of symmetry 3, so that the ratio of phosphine to solvent is 8:1. The P atom adopts a pyramidal coordination geometry.http://scripts.iucr.org/cgi-bin/paper?tk2251 Quinoxaline3-aminophenolwater (212)- April 23, 2008 The asymmetric unit of the title compound, 2C8H6N2C6H7NO2H2O, contains two quinoxaline molecules, one molecule of 3-aminophenol and two water molecules which are hydrogen bonded to form a two-dimensional polymeric structure. Each of the symmetry-independent quinoxaline molecules forms separate stacks of different symmetry. In one set of stacks, the molecules are related by a screw axis and are slightly tilted dihedral angle = 7.12(1). In the second set of stacks, adjacent molecules are parallel.http://scripts.iucr.org/cgi-bin/paper?fl2194 8-Hydroxy-5,6,7-trimethoxy-2-phenyl-4H-chromen-4-one- April 23, 2008 In the title compound, C18H16O6, the benzopyran group is essentially planar, with the O atoms of the substituent groups lying close to its mean plane. The molecular conformation is governed by intramolecular interactions. The crystal packing is mainly determined by one classical intermolecular hydrogen bond which gives rise to the formation of an infinite chain along the a axis.http://scripts.iucr.org/cgi-bin/paper?bg2176 Methyl (2S,3S)-3,4-O-(2,3-dimethoxybutane-2,3-diyl)--l-rhamnopyranoside: a glycosyl acceptor- April 23, 2008 The title compound, C13H24O7, is the product of the ketalization of methyl l-(+)-rhamnopyranoside with 2,3-butanedione. It crystallizes with two molecules in the asymmetric unit, which are connected by OH...O hydrogen bonds. The C-3,4 diequatorial hydroxy groups of the methyl l-(+)-rhamnopyranoside were protected, leaving the C-2 hydroxy group free. The l-(+)-rhamnopyranoside and 2,3-dimethoxybutane-2,3-diyl rings adopt chair conformations and all methoxy groups are in axial positions. The...http://scripts.iucr.org/cgi-bin/paper?bt2683 1,3-Diprop-2-ynyl-1H-imidazol-3-ium bromide- April 23, 2008 In the title salt, C9H9N2+Br, the ethynyl groups are nearly antiparallel to each other the angle between the two ethynyl groups is179.7(2). No classical hydrogen bonds or interactions are observed. The molecules are linked by CH...Br hydrogen bonds. The bromide anions are involved in interactions with three H atoms.http://scripts.iucr.org/cgi-bin/paper?fb2094 2-(4-Methylbenzoyl)benzoic acid monohydrate- April 23, 2008 In the title compound, C15H12O3H2O, the two rings are oriented at a dihedral angle of 69.12(3). In the crystal structure, intermolecular OH...O hydrogen bonds link the molecules into a three-dimensional framework.http://scripts.iucr.org/cgi-bin/paper?hk2446 1,3-Bis4-(4-pyridyl)pyrimidin-2-ylsulfanylpropane- April 23, 2008 In the title compound, C21H18N6S2, the dihedral angles between the aromatic rings in the two 4-(4-pyridyl)pyrimidine residues are 23.45(13) and 2.67(14). Whereas one of the CSCC torsion angles corresponds to a staggered conformation, the other is gauche.http://scripts.iucr.org/cgi-bin/paper?bt2695 (4R,5R,6S,7R,8S,9R,10S,13S)-7,8-Epoxymomilactone-A- April 23, 2008 The title compound, C20H26O4, was extracted from Leucas Urticifolia, a wild Lamiaceae herb distributed in the Punjab, Baluchistan, Sindh and the Rajputana desert of Pakistan. The plant is utilized for various medicinal applications by the local community. The title compound is based on the pimaranediterpene skeleton. The molecule exhibits an epoxy ring fused to momilactone-A, leading to a pentacyclic molecular structure. The absolute configuration was assigned by comparison with the crystal...http://scripts.iucr.org/cgi-bin/paper?im2057 |