Search results for "Hydrogen bond"
showing 10 items of 1310 documents
Crystal structure of (E)-4-methyl-N-{2-[2-(4-nitrobenzylidene)hydrazin-1-yl]-2-oxoethyl}benzenesulfonamideN,N-dimethylformamide monosolvate
2017
The molecule of the title Schiff base compound, C16H16N4O5S·C3H7NO, displays atransconformation with respect to the C=N double bond. The C—N and N—N bonds are relatively short compared to their normal bond lengths, indicating some degree of delocalization in the molecule. The molecule is bent at the S atom, with an S—N—C—C torsion angle of 164.48 (11)°. The dihedral angle between the two aromatic rings is 84.594 (7)°. Intermolecular N—H...O and C —H...O hydrogen bonds connect centrosymmetrically related molecules into dimers forming rings ofR33(11) andR22(10) graph-set motif stacked along theaaxis into a columnar arrangement. The molecular columns are further linked into a three-dimensional…
Crystal structure of the tripeptideN-(benzyloxycarbonyl)glycylglycyl-L-norvaline
2015
The title tripeptide, C17H23N3O6, contains a nonproteinogenic C-terminal amino acid residue, norvaline, which is an isomer of the amino acid valine. Norvaline, unlike valine, has an unbranched side chain. The molecule has a Gly–Gly segment which adopts an extended conformation. The norvaline residue also adopts an extended backbone conformation while its side chain has ag+tconformation. In the crystal lattice, N—H...O and O—H...O hydrogen bonds stabilize the packing. Molecules translated along the crystallographicaaxis associate through an N—H...O hydrogen bond. The remaining three hydrogen bonds are between molecules related by a21screw axis.
Conformational investigation of α,β‐dehydropeptides Part VI. Molecular and crystal structure of benzyloxycarbonylglycyl‐(Z )‐dehydrophenylalanine
1994
The structure of a peptide containing C-terminal dehydrophenylalanine, Z-Gly-(Z)-delta Phe (C19H18N2O5, MW = 354) was determined from single-crystal X-ray diffraction data. Needle-shaped crystals were grown from a 1:1 mixture of methanol-acetone in the monoclinic space group P2(1) with a = 14.717(4), b = 4.941(2), c = 12.073(4) A, beta = 103.72(4) degrees; V = 852.86(8) A3, Z = 2 and Dc = 1.32 g cm-3. The structure was solved by direct methods using SHELXS-86 and refined to a final R-index of 0.032 for 1714 observed reflections. The peptide adopts a conformation folded at the glycine residue, and principal torsion angles are omega 0 = -167.6(2) degrees, phi 1 = -71.8(3) degrees, psi 1 = -31…
Reactivity of bis(cyclohexylammonium) 4-nitrophenylphosphate with SnMe3 Cl. X-ray structure of 4-NO2 C6 H4 PO4(SnMe3)2·H2 O
2014
The reaction of bis(cyclohexylammonium) 4-nitrophenylphosphate with Me3 SnCl (1:2) under reflux in ethanol yielded the title compound 4-NO2 C6 H4 PO4(SnMe3)2H2 O (1). The X-ray crystallographic analysis achieved on single crystals obtained by slow evaporation at room temperature revealed the formation of an unexpected supramolecular coordination network. The elementary building block can be viewed as two Me3 Sn moieties linked by a bridging 4-nitrophenylphosphate ligand. The two tin atoms are five-coordinated and describe a trans-Me3 SnO2 geometry in a trigonal bipyramidal arrangement. However, the Sn atoms are distinct, exhibiting two different environments. Thus, one is linked to two axia…
The subtle balance of weak supramolecular interactions: The hierarchy of halogen and hydrogen bonds in haloanilinium and halopyridinium salts
2010
The series of haloanilinium and halopyridinium salts: 4-IPhNH₃Cl (1), 4-IPhNH₃Br (5), 4-IPhNH₃H₂PO₄ (6), 4-ClPhNH₃H₂PO₄ (8), 3-IPyBnCl (9), 3-IPyHCl (10) and 3-IPyH-5NIPA (3-iodopyridinium 5-nitroisophthalate, 13), where hydrogen or/and halogen bonding represents the most relevant non-covalent interactions, has been prepared and characterized by single crystal X-ray diffraction. This series was further complemented by extracting some relevant crystal structures: 4-BrPhNH3Cl (2, CCDC ref. code TAWRAL), 4-ClPhNH3Cl (3, CURGOL), 4-FPhNH3Cl (4, ANLCLA), 4-BrPhNH3H2PO4, (7, UGISEI), 3-BrPyHCl, (11, CIHBAX) and 3-ClPyHCl, (12, VOQMUJ) from Cambridge Structural Database for sake of comparison. Bas…
4-Chloronaphthalen-1-yl 4-methylbenzenesulfonate
2018
In the title compound, C17H13ClO3S, the naphthalene ring system and the benzene ring of the tosylate substituent are inclined to one another by 55.32 (5)°. The crystal structure features weak intermolecular C—H...O hydrogen bonds, one of which forms inversion dimers. Additional C—H...O hydrogen bonds and weak Cl...Cl halogen bonds stack the molecules along the b-axis direction.
3,5-Dimethoxyphenyl 4-methylbenzenesulfonate
2017
Molecules of the title compound, C15H16O5S, are composed of a 3,5-dimethoxyphenyl moiety substituted with a toluene-4-sulfonate group. The dihedral angle between two aromatic rings is 57.23 (4)°. In the crystal, molecules are connected by weak C—H...O hydrogen bonds and S...O van der Waals interactions.
Crystal structure of 3-(tri-phenyl-phosphoranyl-idene)-2,5-di-hydro-furan-2,5-dione tetra-hydro-furan monosolvate.
2018
The title pseudo-polymorph of 3-(triphenylphosphoranylidene)-2,5-dihydrofuran-2,5-dione crystallizes with a tetrahydrofuran solvent molecule, viz. C22H17O3P·C4H8O. The succinic anhydride ring is approximately planar (r.m.s. deviation = 0.032 Å). The tetrahydrofuran molecule is disordered over two orientations about a pseudo-twofold axis with refined occupancy ratio 0.718 (4):0.282 (4). In the crystal, C—H...O hydrogen bonds link molecules of the dihydrofuran-2,5-dione derivative into chains parallel to the b axis and arranged into layers stacked along [100] alternating with hydrogen-bonded tetrahydrofuran layers.
Crystal structure of bis(2-aminoanilinium) hydrogen phosphate
2016
In the title compound, the hydrogen phosphate anions are linked by O—H⋯O hydrogen bonds into chains parallel to [100]. The inorganic anionic chains and the organic cations are linked by N—H⋯O and N—H⋯N hydrogen bonds, forming a two-dimensional supramolecular network extending parallel to (001).
2-[4-(Dimethylamino)phenyl]-3,3-difluoro-3H-naphtho[1,2-e][1,3,2]oxazaborinin-2-ium-3-uide
2017
In the title compound, C19H17BF2N2O, a twist about the N—C single bond is observed, making the cross conjugation not as efficient as in the case of a planar structure. The borone complex has tetrahedral geometry. In the crystal, molecules are conected by weak C—H...F hydrogen bonds.