In the title compound, (C(7)H(11)N(2))(2)[SnBr(4)(C(7)H(7))(2)], the tetra-bromidobis(4-methyl-phen-yl)stannate(IV) anion possesses a centre of inversion located at the Sn(IV) atom. In the crystal structure, two inversion-related cations are linked to the anion via weak N-H⋯Br hydrogen bonds.
In the title compound, (C(7)H(11)N(2))(2)[SnBr(4)(C(6)H(4)Cl)(2)]·C(6)H(4)BrCl, the Sn(IV) atom in the tetra-bromidobis(4-chloro-phen-yl)stannate(IV) anion lies on a centre of inversion. The distances between the 4-(dimethyl-amino)pyridinium N atom and the Br atoms of the anion are 3.450 (2) and 3.452 (2) Å, suggesting weak hydrogen bonding. The 4-bromo-chloro-benzene solvent mol-ecule, which is a bromination by-product from the reaction, is disordered about a twofold rotation axis with approximately equal occupancy.
The title compound, [Sn(C(6)H(5))(3)(C(17)H(25)O(3)S)](n), comprises two symmetry-independent five-coordinated triphenyl-tin mol-ecules which are linked by carboxyl-ate bridges into a polymeric chain. The Sn(IV) atom is in a distorted trans-C(3)SnO(2) trigonal-bipyramidal geometry. The presence of two bulky tert-butyl groups on the benzene ring prevents any hydrogen-bonding inter-actions involving the hydroxyl substituents.
The mol-ecule of the title compound, C(17)H(14)N(4)O(4), uses its amide -NH- group to form a hydrogen bond to the amido -C(=O)- group of an adjacent mol-ecule to furnish a linear chain structure. The hydr-oxy group forms an intra-molecular hydrogen bond; the indolyl -NH- unit does not engage in any strong hydrogen-bonding inter-actions.
A cytotoxic bisindole alkaloid possessing an unprecedented structure constituted from the union of an eburnan half and a novel vinylquinoline alkaloid has been isolated from Leuconotis griffithii. The structure was established by analysis of the spectroscopic data and confirmed by X-ray diffraction analysis. A possible biogenetic pathway to the novel quinolinic coupling partner is presented from an Aspidosperma precursor.
The two independent mol-ecules in the asymmetric unit of the title compound, C(15)H(16)N(2)O(3)S, are each linked by an N-H⋯O(sulfon-yl) hydrogen bond into a linear chain that runs along the shortest axis of the triclinic unit cell. The hydr-oxy groups are engaged in intra-molecular hydrogen bonding and the amino N atom shows pyramidal coordination.
The mol-ecule of the title compound, C(8)H(8)N(4)O(3)S, is planar. Adjacent mol-ecules are linked through O-H⋯S, N-H⋯S and N-H⋯O hydrogen bonds into a three-dimensional network.
The title compound, C(14)H(11)BrN(2)O(5)·2H(2)O, crystallizes as hydrogen-bonded sheets. The 2-hydr-oxy group on the benzyl-idene group forms an intra-molecular hydrogen bond to the N atom of the C=N double bond. The amino N atom is a hydrogen-bond donor to a water mol-ecule. The hydr-oxy group on the benzohydrazide group is a hydrogen-bond donor to one acceptor site, whereas each water mol-ecule is a hydrogen-bond donor to two acceptor sites.
The mol-ecule of the title compound, C(13)H(11)N(3)O(5)S, shows a phenyl group and an almost planar intra-molecularly hydrogen-bonded N'-(2-hydr-oxy-5-phenyl-ebenzyl-idene)hydrazino group disposed about the S atom. Adjacent mol-ecules are linked by N-H⋯O(nitro) hydrogen bonds, producing a linear chain that runs along the b axis of the unit cell.
The dinuclear title compound, [Zn(2)(C(19)H(17)N(3)O(2))(2)(H(2)O)(2)]·4C(2)H(6)OS, lies about a center of inversion. The deprotonated monoanion O,N,O-chelates the Zn atom; the hydr-oxy O atom also engages in bonding to the symmetry-related Zn atom so that one N and three O atoms form a square around the metal. The coordination geometry is square-pyramidal, with the apical site occupied by a water mol-ecule. Hydrogen bonds, with the water mol-ecule serving as donor atom, lead to the formation of a linear chain motif. There is an N-H⋯O hydrogen bond between the complex molecule and solvent O atom.
The Cu atom in the title compound, [Cu(C(13)H(9)BrClN(2)O(3)S)(2)], is chelated by two deprotonated Schiff base ligands in a square-planar coordination geometry; the Cu atom lies on a center of inversion. The -NH- group of one anion forms an intra-molecular hydrogen bond to the phenolate atom of the symmetry-related ion.
Leucofoline and leuconoline, representing the first members of the aspidospermatan-aspidospermatan and eburnane-sarpagine subclasses of the bisindole alkaloids, respectively, were isolated from the Malayan Leuconotis griffithii. The structures of these bisindole alkaloids were established using NMR and MS analysis, and in the case of leuconoline, confirmed by X-ray diffraction analysis. Both alkaloids showed weak cytotoxicity towards human KB cells.