A new monoclinic polymorph of dichlorido­tetra­kis(dimethyl sulfoxide)­ruthenium(II)

The title compound, cis,fac-dichloridotetra­kis(dimethyl sulfoxide)-κ3 S,κO-ruthenium(II), [RuCl2(C2H6OS)4], was obtained from newly synthesized ruthenium complexes of 3-amino-2-chloro­pyridine. The Ru atom has a distorted octa­hedral coordination with two cis-oriented chloride ligands and four dimethyl sulfoxide ligands. Three of the sulfoxide ligands are S-bonded in a fac configuration, while the fourth is O-bonded. The title compound represents a new, and fourth, polymorph of the complex. Two other monoclinic forms and an ortho­rhom­bic modification have been reported previously

(R)-Methyl {[(2-carboxybicyclo[2.2.2]octan-1-yl)ammonio]methyl}phosphonate dichloromethane 0.25-solvate

The carboxylic acid molecule of the title compound, C11H20NO5P·0.25CH2Cl2, exists as a zwitterion with the H atom of the phosphonate group being transferred to the imine N atom. In the asymmetric unit, there are two crystallographically independent acid molecules adopting the same absolute configuration and differing slightly in their geometrical parameters. In each molecule, the imino and carboxyl groups are connected via an intramolecular N—H...O hydrogen bond. Intermolecular O—H...O and N—H...O hydrogen bonds induce the formation of layers parallel to the ab plane. The dichloromethane solvent molecule, with a site occupancy of 0.5, is located between the layers

New Heterocyclic Combretastatin A-4 Analogs: Synthesis and Biological Activity of Styryl-2(3H)-benzothiazolones

Here, we describe the synthesis, characterization, and biological activities of a series of 26 new styryl-2(3H)-benzothiazolone analogs of combretastatin-A4 (CA-4). The cytotoxic activities of these compounds were tested in several cell lines (EA.hy926, A549, BEAS-2B, MDA-MB-231, HT-29, MCF-7, and MCF-10A), and the relations between structure and cytotoxicity are discussed. From the series, compound (Z)-3-methyl-6-(3,4,5-trimethoxystyryl)-2(3H)-benzothiazolone (26Z) exhibits the most potent cytotoxic activity (IC50 0.13 ± 0.01 µM) against EA.hy926 cells. 26Z not only inhibits vasculogenesis but also disrupts pre-existing vasculature. 26Z is a microtubule-modulating agent and inhibits a spectrum of angiogenic events in EA.hy926 cells by interfering with endothelial cell invasion, migration, and proliferation. 26Z also shows anti-proliferative activity in CA-4 resistant cells with the following IC50 values: HT-29 (0.008 ± 0.001 µM), MDA-MB-231 (1.35 ± 0.42 µM), and MCF-7 (2.42 ± 0.48 µM). Cell-cycle phase-specific experiments show that 26Z treatment results in G2/M arrest and mitotic spindle multipolarity, suggesting that drug-induced centrosome amplification could promote cell death. Some 26Z-treated adherent cells undergo aberrant cytokinesis, resulting in aneuploidy that perhaps contributes to drug-induced cell death. These data indicate that spindle multipolarity induction by 26Z has an exciting chemotherapeutic potential that merits further investigation