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A single pot, wet chemical route has been applied for the synthesis of polymer supported copper azide, CuN3, nanoparticles (CANP). The hybrid system was used as ‘catalyst-cum-reagent’ for the azide-alkyne cyclo-addition reaction to construct triazole molecules using substituted benzyl bromide and terminal alkyne. The electron donating group containing terminal alkyne produced 5-alkynyl 1,4-disubstituded triazole product whereas for alkyne molecule with terminal electron withdrawing group facilitate the formation of 1,4-disubstituted triazole molecule.

Scandenone (warangalone) is a flavonoid found in Erythrina species and other plant genera. It has been connected with physiological processes in insects, human cells and bacteria. In this article, an overview of the biological importance of this compound is provided. A detailed analysis of its crystal structure and antibacterial properties were investigated. The experimental study was supplemented using density functional theory (DFT) and quantitative structure-activity relationship (QSAR) methods. Scandenone proved most potent against Mycobacterium smegmatis (mc2 155) with MIC below 1 μg/mL. In general, it was more potent against Gram-positive bacteria. Scandenone may be a potential tuberculosis medication.

Dithiocarbamate ligands obtained from primary amines, namely N-phenylaniline, 4-methylaniline and 4-ethylaniline, and represented as L1, L2 and L3 respectively, have been used to prepare some Ni(II), Pd(II) and Pt(II) complexes. The complexes were characterized by NMR, FTIR spectroscopy and elemental analysis. The spectroscopic data showed that the ligands were chelated to the metal ions in a bidentate mode. The complexes [Pt(L1)2], [Pt(L3)2], and [Pd(L1)2] were further characterized by single crystal X-ray analysis and distorted square planar geometries were confirmed in all cases. The magnetic susceptibility measurements of the nickel complexes suggest a square planar geometry for the diamagnetic compounds. Thermal decomposition studies of the complexes gave their respective metal sulfides as residues. Geometry optimization and harmonic frequency calculations of the ligands and the complexes were carried out using density functional theory (DFT). Molecular electrostatic potential energy calculations were used to support the coordination through the dithio-sulfur groups of the three dithiocarbamate ligands. Non-covalent interaction (NCI) theory analysis was used to reveal the different intra and intermolecular interactions in the hydrogen bonded structures of the platinum and palladium complexes. Antimicrobial screening, conducted using selected microbes, showed that the complexes gave moderate to very active antimicrobial activities against Gram negative (Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa), Gram positive (Bacillus cereus and Staphylococcus aureus) and fungi (Candida albicans and Aspergillus flavus) organisms at a concentration of at 50 μg/mL. However, the [Pt(L3)2] complex gave the best antimicrobial properties with an inhibitory zone range of 8–26 mm.

A complementary application of three analytical techniques, viz. multidimensional nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS), and single-crystal X-ray diffractometry was required to identify and refine two natural products isolated from Millettia versicolor and solvent of crystallization. The two compounds, namely 3-(2H-1,3-benzodioxol-5-yl)-6-methoxy-8,8-dimethyl-4H,8H-pyrano[2,3-h]chromen-4-one, or durmillone, (I), and (2E)-1-(4-{[(2E)-3,7-dimethylocta-2,6-dien-1-yl]oxy}-2-hydroxyphenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one, (II), could not be separated by routine column chromatography and cocrystallized in a 2:1 ratio with 0.13 molecules of ethanol solvent. Compound (II) and ethanol could not be initially identified by single-crystal X-ray analysis due to complex disorder in the aliphatic chain region of (II). Mass spectrometry ensured that (II) represented only one species disordered over several positions in the solid state, rather than several species cohabitating on the same crystallographic site. The atomic identification and connectivity in (II) were established by several 2D (two-dimensional) NMR techniques, which in turn relied on a knowledge of its exact mass. The derived connectivity was then used in the single-crystal analysis to model the disorder of the aliphatic chain in (II) over three positions and allowed identification of a partially occupied ethanol solvent molecule that was disordered over an inversion center. The disordered moieties were refined with restraints and constraints.

The title compound, [Cd2(C7H10NS2)4], is a neutral dinuclear cadmium(II) complex bearing four bisN,N-diallyldithiocarbamate ligands coordinating to two CdIIcations. In each of the monomeric subunits, there are four S atoms of two dithiocarbamate ligands [Cd—S = 2.5558 (3), 2.8016 (3), 2.6050 (3) and 2.5709 (3) Å] that coordinate to one CdIIatom in a bidentate mode. The dimers are located over an inversion centre bridged by two additional bridging Cd—S bonds [2.6021 (3) Å], leading to a substantial distortion of the geometry of the monomeric subunit from the expected square-planar geometry. The five-coordinate environment around each of the CdIIions in the dimer is best described as substantially tetragonally distorted square pyramidal. The dithiocarbamate groups are themselves planar and are also coplanar with the CdIIions. The negative charge on these groups is delocalized by resonance across the S atoms bound to the CdIIcation. This delocalization of the π electrons in the dithiocarbamate groups also extends to the C—N bonds as they reveal significant double bond character [C—N = 1.3213 (16) and 1.3333 (15) Å].

The acidity of the amine H atoms and the consequent salt formation ability of ethylenedinitramine (EDNA) were analyzed in an attempt to improve the thermal stability of EDNA. Two short-chain alkanediamine bases, namely propane-1,3-diamine and butane-1,4-diamine, were chosen for this purpose. The resulting salts, namely propane-1,3-diaminium N,N′-dinitroethylenediazanide, C3H12N2 2+·C2H4N4O4 2−, and butane-1,4-diaminium N,N′-dinitroethylenediazanide, C4H14N2 2+·C2H4N4O4 2−, crystallize in the orthorhombic space group Pbca and the monoclinic space group P21/n, respectively. The resulting salts display extensive hydrogen-bonding networks because of the presence of ammonium and diazenide ions in the crystal lattice. This results in an enhanced thermal stability and raises the thermal decomposition temperatures to 202 and 221 °C compared to 180 °C for EDNA. The extensive hydrogen bonding present also plays a crucial role in lowering the sensitivity to impact of these energetic salts.

C3H11N2I, monoclinic, P21/n (no. 14), a = 5.0152(2) Å, b = 10.1470(4) Å, c = 14.1852(5) Å, β = 96.501(2)°, V = 717.23(5) Å3, Z = 4, R gt(F) = 0.0174, wR ref(F 2) = 0.0411, T = 100 K.