2-(2-Amino-4-nitrophenyl)-7-nitro-4H-3,1-benzoxazin-4-one

The use of the EPSRC X-ray crystallographic service (Coles & Gale, 2012[Coles, S. J. & Gale, P. A. (2012). Chem. Sci. 3, 683-689.]) at the University of Southampton, England, and the valuable assistance of the staff there is gratefully acknowledged. JLW acknowledges support from CAPES (Brazil). Structural studies are supported by the Ministry of Higher Education (Malaysia) and the University of Malaya through the High-Impact Research scheme (UM.C/HIR/MOHE/SC/3).Peer reviewedPublisher PD

catena-Poly[[[bis[(-)-O-bornyldithiocarbonato-κ2S,S\u27]nickel(II)]-μ-4,4\u27-bipyridine-κ2N:N\u27] chloroform disolvate]

The Ni atom in the linear polymeric title complex, {[Ni(C11H17OS2)2(C10H8N2)]&middot;2CHC13}n or {Ni[S2C(-)-OC10H17)]2(NC5H4C5H4N)&middot;2CHC13}n, is octahedrally coordinated within a trans-N2S4 donor set. There are two crystallographically independent polymers and two independent CHC13 molecules in the structure. For each polymer unit, the Ni atom and the axis of the 4,4\u27-bipyridine ligand are located on a twofold axis.<br /

Hexameric trimethylsilylmethyloxotin acetate, [(Me3SiCH2)Sn(O)(OAc)]6

The centrosymmetric hexanuclear title compound, hexa-&mu;2-acetato-hexa-&mu;3-oxo-hexakis[(trimethylsilylmethyl)tin], [Sn6O6(C2H3O2)6(C4H11Si)6], adopts a \u27drum\u27 structure in which two [(Me3SiCH2)SnO]3 caps are linked to each other via six &mu;3-O atoms and six bidentate bridging acetate groups. A CO5 donor set defines a distorted octahedral environment for each of the three independent Sn atoms. <br /

Designing, physiochemical confirmation, evaluation of biological and in-silico potential of Triorganotin(IV) complexes

FTIR, NMR, CHN and single crystal X-ray crystallography were used to validate a series of three new triorganotin(IV) carboxylate complexes, R3Sn(L) for R=Methyl(1), n-Butyl(2) and Phenyl(3), obtained from LH=4-[(2,5-dimethoxyphenyl)carbamoyl]butanoic acid. The coupling constant and θC-Sn-C values in solution-state NMR data suggest a 5-coordinated environment around the Sn centre. In the crystal of 1, the carboxylate is bidentate bridging leading to a zigzag chain with the Sn centre having a distorted trigonal-bipyramidal geometry. The compounds were evaluated for their interaction with salmon sperm DNA and found that they interact through an intercalative mode resulting in hypochromism and bathochromic shift as confirmed by the UV-visible spectroscopic and viscometric techniques. The findings of anti-microbial activity performed on five bacterial and two fungus strains demonstrate that some of the compounds exhibit >80% inhibition of certain bacteria and >100% inhibition of certain fungal strains. The compounds were also evaluated for cell viability tested on human embryonic kidney cell (HEC-239) and human red blood cells (RBC). The anti-cancer potential of the compounds was assessed using cis-platin as a standard against human malignant glioma U87 (MG-U87) cell lines, and 1 was shown to be the most potent (IC50: 148.979 μM) at a 50μM dose. The DPPH anti-oxidant activity results revealed a 91% maximum scavenging activity for 1. The compounds follow the principles of drug-likeness and have good bioavailability potential, according to an in silico analysis conducted using the SwissADME webserve

Prevalence of the thioamide {···H-N-C=S}2 synthon-solid-state (X-ray crystallography), solution (NMR) and gas-phase (theoretical) structures of O-methyl-N-aryl-thiocarbamides

Structural investigations, i.e. solid-state (X-ray), solution (1H NMR) and gas-phase (theoretical), on molecules with the general formula MeOC(S)N(H)C6H4-4-Y: Y = H (1), NO2 (2), C(O)Me (3), Cl (4) have shown a general preference for the adoption of an E-conformation about the central C&ndash;N bond. Such a conformation allows for the formation of a dimeric hydrogen-bonded {H&ndash;N&ndash;C=S}2 synthon as the building block. In the cases of 1&ndash;3, additional C&ndash;H...O interactions give rise to the formation of tapes of varying topology. A theoretical analysis shows that the preference for the E-conformation is about the same as the crystal packing stabilisation energy and consistent with this, the compound with Y = C(O)OMe, (5), adopts a Z-conformation in the solid-state that facilitates the formation of N&ndash;H...O, C&ndash;H...O and C&ndash;H...S interactions, leading to a layer structure. Global crystal packing considerations are shown to be imperative in dictating the conformational form of molecules 1&ndash;5.<br /

In vitro antibacterial and time kill evaluation of mononuclear phosphanegold(I) dithiocarbamates

Four compounds, R3PAu[S2CN(CH2CH2OH)2], R = Ph (1) and cyclohexyl (2), and Et3PAuS2CNRꞌ2, Rꞌ = Rꞌ = Et (3) and Rꞌ2 = (CH2)4 (4), have been evaluated for antibacterial activity against a panel of 24 Gram positive (8) and Gram negative (16) bacteria. Based on minimum inhibitory concentration (MIC) scores, compounds 1 and 2 were shown to be specifically potent against Gram positive bacteria whereas compounds 3 and, to a lesser extent, 4 exhibited broad range activity. All four compounds were active against methicillin resistant Staphylococcus aureus (MRSA). Time kill assays revealed the compounds to exhibit both time- and concentration-dependent pharmacokinetics against susceptible bacteria. Each compound was bactericidal against one or more bacteria with 3 being especially potent after 8 h exposure; compounds 1 and 3 were bactericidal against MRSA. Compound 3 was the most effective bactericide across the series especially toward B. subtilis, S. saprophyticus, A. hydrophila, P. vulgaris, and V. parahaemolyticus. This study demonstrates the potential of this class of compounds as antibacterial agents, either broad range or against specific bacteria

New insight into the structural, electrochemical and biological aspects of macrocylic Cu(II) complexes derived from S-substituted dithiocarbazate Schiff bases

Copper (II) complexes synthesized from the products of condensation of S-methyl- and S-benzyldithiocarbazate with 2,5-hexanedione (SMHDH2 and SBHDH2 respectively) have been characterized using various physicochemical (elemental analysis, molar conductivity, magnetic susceptibility) and spectroscopic (infrared, electronic) methods. The structures of SMHDH2, its copper (II) complex, CuSMHD, and the related CuSBHD complex as well as a pyrrole byproduct, SBPY, have been determined by single crystal X-ray diffraction. In order to provide more insight into the behaviour of the complexes in solution, electron paramagnetic resonance (EPR) and electrochemical experiments were performed. Antibacterial activity and cytotoxicity were evaluated. The compounds, dissolved in 0.5% and 5% DMSO, showed a wide range of antibacterial activity against 10 strains of Gram-positive and Gram-negative bacteria. Investigations of the effects of efflux pumps and membrane penetration on antibacterial activity are reported herein. Antiproliferation activity was observed to be enhanced by complexation with copper. Preliminary screening showed Cu complexes are strongly active against human breast adenocarcinoma cancer cell lines MDA-MB-231 and MCF-7

Molecular and supramolecular chemistry of mono- and di-selenium analogues of metal dithiocarbamates

This bibliographic review summarises the coordination chemistry of mono- and diselenium analogues of metal dithiocarbamate ligands, [RRꞌNCS2]-, as revealed by X-ray crystallography and spectroscopy (77Se NMR and infrared). The Se-ligands are usually chelating but, bridging modes, up to 4, are known. Reflecting the larger size, greater polarisability and presence of a polar-cap (-hole), selenium atoms are more likely to be involved in secondary-bonding (chalcogen-bonding) than sulphur when a competition exists. Isostructural relationships are established across the series in about one-third of the structures

Three ammonium salts of sulfathiazole: crystallography and anti-microbial assay

The crystal and molecular structures of three ammonium salts derived from sulfathiazole are described. In each case, the anion is in the azanide form, features an intramolecular S←O interaction, and adopts a U-shape. The structures of two cations, [R(HOCH2CH2)NH2]+, namely for R = Me (1) and iPr (2), are unprecedented in the crystallographic literature. Extensive hydrogen bonding is observed in all crystal structures and leads to a two-dimensional array for 1, and three-dimensional architectures for each of 2 and 3 (R = CH2CH2OH). The salts exhibited anti-microbial activity against a range of Gram-positive and Gram-negative bacteria, and proved bactericidal toward Vibrio parahaemolyticus, but had no advantage over sulfathiazole itself