No abstract

An improved crystal structure of the title compound, C30H30O8 (systematic name: 1,1′,6,6′,7,7′-hexa­hydroxy-5,5′-diisopropyl-3,3′-dimeth­yl[2,2′-bi­naphthalene]-8,8′-dicarbaldehyde), was determined based on modern CCD data. Compared to the previous structure [Talipov et al. (1985). Khim. Prirod. Soedin. (Chem. Nat. Prod.), 6, 20–24], geometrical precision has been improved (typical C—C bond-distance s.u. = 0.002 Å in the present structure compared to 0.005 Å in the previous structure) and the locations of several H atoms have been corrected. The gossypol mol­ecules are in the aldehyde tautomeric form and the dihedral angle between the naphthyl fragments is 80.42 (4)°. Four intra­molecular O—H⋯O hydrogen bonds are formed. In the crystal, inversion dimers with graph-set motif R 2 2(20) are formed by pairs of O—H⋯O hydrogen bonds; another pair of O—H⋯O hydrogen bonds with the same graph-set motif links the dimers into [001] chains. The packing of such chains in the crystal leads to the formation of channels (diameter = 5–8 Å) propagating in the [101] direction. The channels presumably contain highly disordered solvent mol­ecules; their contribution to the scattering was removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] routine in PLATON and the stated mol­ecular mass, density etc., do not take them into account.

No abstract

Heterocyclic nucleus 1,3,4-thiadiazole constitutes an important class of compounds for new drug development. The synthesis of novel thiadiazole derivatives and investigation of their chemical and biological behavior have gained more importance in recent decades. During the recent years, there has been intense investigation of different classes of thiadiazole compounds, many of which possess extensive biological activities. We will discuss a novel extracted isomers of 1,3,4-thiadiazoles derivatives and their possibilities for pharmaceutical and industrial importance. The process of extraction brought to the formation isomers that differ chemically and on crystallographic parameters. The new derivatives of 1,3,4-thiadiazole, isomers with brutto-formula C13H14N2O2S3, crystallize in the triclinic and monoclinic systems, space groups P-1 and P21/c, respectively. Inter-and intramolecular hydrogen bonds help to stabilize the structures. Both hydrogen bonds networks can be described using graph set theory. They will be discussed in detail. The present review highlights the recently synthesized derivatives of 1,3,4-thiadiazole possessing important biological activities.This project is funding in the framework of grant A9-T-050-Uzbekistan on the synthese and study of the antitumant activity of new compounds.

The organic–inorganic complex salt, (C8H10N3)3[La(NO3)6], comprises a network of N-protonated 2-amino-1-methylbenzimidazolium cations and hexakis(nitrato)lanthanate(III) anions. The LaIII atom is twelve-coordinate within a distorted icosahedral environment. In the unit cell, each pair of the LaIII atoms lie nearly on one of the crystallographic glide planes. In the crystal structure, there are several N—H...O hydrogen-bonding interactions between the cations and terminal oxygen atoms from the nitrate moieties of the [La(NO3)6]3– anion. Additional weak C—H...O hydrogen bonds between the cations and anions consolidate the three-dimensional arrangement of the structure. A packing analysis was performed to check the strength of the crystal packing.