Project description:A new pyridine-fused seleno-diazo-lium salt, 3-(phenyl-selan-yl)[1,2,4]selena-diazolo[4,5-a]pyridin-4-ylium chloride di-chloro-methane 0.352-solvate, C12H9N2Se2 +·Cl-·0.352CH2Cl2, was obtained from the reaction between 2-pyridyl-selenenyl chloride and phenyl-seleno-cyanate. Single-crystal structural analysis revealed the presence of C-H⋯N, C-H⋯Cl-, C-H⋯Se hydrogen bonds as well as chalcogen-chalcogen (Se⋯Se) and chalcogen-halogen (Se⋯Cl-) inter-actions. Non-covalent inter-actions were explored by DFT calculations followed by topological analysis of the electron density distribution (QTAIM analysis). The structure consists of pairs of seleno-diazo-lium moieties arranged in a head-to-tail fashion surrounding disordered di-chloro-methane mol-ecules. The assemblies are connected by C-H⋯Cl- and C-H⋯N hydrogen bonds, forming layers, which stack along the c-axis direction connected by bifurcated Se⋯Cl-⋯H-C inter-actions.
Project description:In the title compound, C12H14BN, the complete mol-ecule is generated by a crystallographic twofold axis, with two C atoms, the B atom and the N atom lying on the rotation axis. The dihedral angle between the bora-benzene and pyridine rings is 81.20 (6)°. As well as dative electron donation from the N atom to the B atom [B-N = 1.5659 (18) Å], the methyl substituents on the lutidine ring shield the B atom, which further stabilizes the mol-ecule. In the crystal, weak aromatic π-π stacking between the pyridine rings [centroid-centroid separation = 3.6268 (9) Å] is observed, which generates [001] columns of mol-ecules.
Project description:In the title adduct, C5H5N·I2, the N-I distance [2.424 (8) Å] is remarkably shorter than the sum of the van der Waals radii. The line through the I atoms forms an angle of 78.39 (16)° with the normal to the pyridine ring.
Project description:The hydro-chloride salt of isonicotinamide, C6H7N2O(+)·Cl(-), has been synthesized from a dilute solution of hydro-chloric acid in aceto-nitrile. The compound displays monoclinic symmetry (space group C2/c) at 150 K, similar to the related hydro-chloride salt of nicotinamide. The asymmetric unit contains one protonated isonicotinamide mol-ecule and a chloride anion. An array of hydrogen-bonding inter-actions, including a peculiar bifurcated pyridinium-chloride inter-action, results in linear chains running almost perpendicularly in the [150] and [1-50] directions within the structure. A description of the hydrogen-bonding network and comparison with similar compounds are presented.
Project description:The title compound {systematic name: bis-[2-(1,3-dioxoisoindol-2-yl)eth-yl]aza-nium chloride dihydrate}, C20H18N3O4 +·Cl-·2H2O, is a phthalimide-protected polyamine that was synthesized by a previous method. It was characterized by ESI-MS, 1H NMR, and FT-IR. Crystals were grown from a solution of H2O and 0.1 M HCl. The central nitro-gen atom is protonated and forms hydrogen bonds with the chloride ion and a water mol-ecule. The two phthalimide units make a dihedral angle of 22.07 (3)°. The crystal packing features a hydrogen-bond network, two-coordinated chloride, and off-set π-π stacking.
Project description:In the centrosymmetric (racemic) title compound, chlorido-(3-cyclo-hexhyl-2-phenyl-1,3-thia-zolidin-4-one-κO)tri-phenyl-tin(IV), [Sn(C6H5)3Cl(C15H19NOS)], the tin(IV) atom exhibits a trigonal-bipyramidal coordination geometry with the three phenyl groups in equatorial positions and the chloride anion and ligand oxygen atom present at axial sites [O-Sn-Cl = 175.07 (14)°]. The thia-zolidinone ring of the ligand adopts an envelope conformation with the S atom as the flap. The dihedral angles between the heterocycle ring plane (all atoms) are 44.3 (9)° with respect to the pendant C-phenyl plane and 34.3 (11)° to the N-cyclo-hexyl ring (all atoms). The C-phenyl and N-cyclo-hexyl ring are close to orthogonal to each other, with a dihedral angle of 81.1 (4)° between them. In the crystal, mol-ecules are linked by weak C-H⋯Cl hydrogen bonds to generate [001] chains.
Project description:A synthetic study in the Cd-Se-O-Cl system led to formation of the new oxochloride compound Cd4(SeO3)2OCl2 via solid state reactions. The compound crystallizes in the orthorhombic space group Fmmm with cell parameters a = 7.3610(3) Å, b = 15.4936(2) Å, c = 17.5603(3) Å, Z = 8, S = 0.969, F(000) = 2800, R = 0.0185, Rw = 0.0384. Single crystal X-ray data were collected at 293 K. The crystal structure can be considered as layered and the building units are distorted [Cd(1)O6] octahedra, distorted [Cd(2)O8] cubes, irregular [Cd(3)O4Cl2] polyhedra and SeO3E trigonal pyramids. There are two crystallographically unique Cl atoms that both are half occupied. Thermogravimetric studies show that the compound starts to decompose at 500°C. The crystal structure of the new compound is closely related to the previously described compound Cd4(SeO3)2Cl4(H2O).
Project description:Polyamines are essential in all branches of life. Spermidine synthase (putrescine aminopropyltransferase, PAPT) catalyzes the biosynthesis of spermidine, a ubiquitous polyamine. The crystal structure of the PAPT from Thermotoga maritima (TmPAPT) has been solved to 1.5 A resolution in the presence and absence of AdoDATO (S-adenosyl-1,8-diamino-3-thiooctane), a compound containing both substrate and product moieties. This, the first structure of an aminopropyltransferase, reveals deep cavities for binding substrate and cofactor, and a loop that envelops the active site. The AdoDATO binding site is lined with residues conserved in PAPT enzymes from bacteria to humans, suggesting a universal catalytic mechanism. Other conserved residues act sterically to provide a structural basis for polyamine specificity. The enzyme is tetrameric; each monomer consists of a C-terminal domain with a Rossmann-like fold and an N-terminal beta-stranded domain. The tetramer is assembled using a novel barrel-type oligomerization motif.
Project description:The title adduct, chlorido-(2,3-diphenyl-3,4,5,6-tetra-hydro-2H-1,3-thia-zin-4-one-κO)tri-phenyl-tin, [Sn(C6H5)3Cl(C16H15NOS)], resulted from reaction of 2,3-diphenyl-3,4,5,6-tetra-hydro-2H-1,3-thia-zin-4-one with tri-phenyl-tin chloride. The thia-zine ring has an envelope conformation with the S atom forming the flap. The mol-ecule has five phenyl rings, two of them attached to the thia-zine ring at positions 2 and 3, and three in coordination with the Sn(IV) atom. The three rings of the tri-phenyl-tin group are involved in intra-molecular inter-actions of different types, C-H⋯O, edge-to-face (or T-type) π-π inter-actions with the 3-phenyl ring of the thia-zine, T-type inter-actions with both phenyl rings of the thia-zine etc. On the other hand, all the phenyl rings participate in inter-molecular π-π inter-actions. There is one instance of a 'parallel-displaced'-type inter-action extending continuously along the a-axis direction and seven instances of T-type inter-actions stabilizing the crystal lattice.
Project description:In the title compound, C12H13N2 (+)·Cl(-), the chloride salt of 1,1'-di-phenyl-hydrazine, the phenyl rings are inclined to one another by 78.63 (17)°. The N-(+)NH3 bond lengths is 1.445 (3) Å, and the N-Cphen-yl bond lengths are 1.435 (3) and 1.447 (4) Å. In the crystal, mol-ecules are linked via N-H⋯Cl hydrogen bonds, forming chains along [10-1], which enclose two adjacent R (4) 2(6) ring motifs. The chains are reinforced by C-H⋯Cl hydrogen bonds.