Kamini Kapoor

Tubulin inhibitors from an endophytic fungus isolated from Cedrus deodara.

From an endophytic fungus, a close relative of Talaromyces sp., found in association with Cedrus deodara, four compounds including two new ones (2 and 4) were isolated and characterized. The structures of two compounds (1 and 4) were confirmed by X-ray crystallography. The compounds displayed a range of cytotoxicities against human cancer cell lines (HCT-116, A-549, HEP-1, THP-1, and PC-3). All the compounds were found to induce apoptosis in HL-60 cells, as evidenced by fluorescence and scanning electron microscopy studies. Also, the compounds caused significant microtubule inhibition in HL-60 cells.

Ethyl 6-(4-bromo­phen­yl)-4-(4-fluoro­phen­yl)-2-oxocyclo­hex-3-ene-1-carboxyl­ate

There are two independent molecules in the asymmetric unit of the title compound, C21H18BrFO3, in which the dihedral angles between the fluorophenyl and bromophenyl groups are 77.0 (1) and 85.8 (1)°. In one of the molecules, two methine C—H groups of the cyclohexene ring are disordered over two sets of sites in a 0.53 (2):0.47 (2) ratio. In both molecules, the atoms of the ethyl group were refined as disordered over two sets of sites with occupancies of 0.67 (2):0.33 (2) and 0.63 (4):0.37 (4). The cyclohexene rings have slightly distorted sofa conformations in both molecules. In the crystal, C—H⋯O interactions link molecules into chains along the b axis.

Psilostachyin, acetylated pseudoguaianolides and their analogues: Preparation and evaluation of their anti-inflammatory potential

Naturally occurring acetylated pseudoguaianolides and psilostachyin including their analogues were synthesized. The structure of semi-synthetic psilostachyin was also confirmed by X-ray crystallography. The anti-inflammatory potential of all the derivatives has been evaluated through in vitro expression of TNF-α, IL-1β and IL-6 in murine neutrophils.

(1Z)-1-[(2E)-3-(4-Bromo­phen­yl)-1-(4-fluoro­phen­yl)prop-2-en-1-yl­idene]-2-(2,4-dinitro­phen­yl)hydrazine

In the title molecule, C21H14BrFN4O4, the mean planes of the two nitro groups form dihedral angles of 3.1 (2) and 7.1 (5)° with the benzene ring to which they are attached. The dinitro-substituted ring forms dihedral angles of 8.6 (2) and 71.9 (2)° with the bromo- and fluoro-substituted benzene rings, respectively. The dihedral angle between the bromo- and fluoro-substituted benzene rings is 80.6 (2)°. There is an intramolecular N—H⋯O hydrogen bond. In the crystal, pairs of weak C—H⋯O hydrogen bonds form inversion dimers. In addition, π–π stacking interactions between the bromo- and dinitro-substituted rings [centroid–centroid separation = 3.768 (2) Å] are observed.

(2-Oxo-2H-benzo[h]chromen-4-yl)methyl morpholine-4-carbodithio-ate.

In the title compound, C19H17NO3S2, the morpholine ring is in a chair conformation. In the coumarin ring system, the dihedral angle between the benzene and pyran rings is 3.9 (1)°. In the crystal, weak C—H⋯O interactions link the molecules into corrugated layers parallel to (102). The crystal packing also exhibits π–π interactions, with distances of 3.644 (1) and 3.677 (1) Å between the centroids of the benzene rings of neighbouring molecules.

(7-Chloro-2-oxo-2H-chromen-4-yl)methyl piperidine-1-carbodithio­ate

In the title compound, C16H16ClNO2S2, the piperidine ring is in a chair conformation. In the coumarin ring system, the dihedral angle between the benzene and pyran rings is 3.5 (1)°. In the crystal, a weak C—H⋯O hydrogen bond links molecules into chains along [001]. In addition, π–π stacking interactions are present involving the benzene and pyran rings, with a centroid-to-centroid distance of 3.712 (2) Å. The crystal studied is a nonmerohedral twin with refined components 0.221 (1) and 0.779 (1).

Bis(μ-N-benzyl-N-furfuryldithio-carbamato)-1:2κS,S':S';2:1κS,S':S'-bis-[(N-benzyl-N-furfuryldithio-carbamato-κS,S')cadmium].

In the centrosymmetric title compound, [Cd2(C13H12NOS2)4], pairs of dithiocarbamate ligands exhibit different structural functions. Each of the terminal ligands is bidentately coordinated to one CdII atom and forms a planar four-membered CS2Cd chelate ring, whereas pairs of the tridentate bridging ligands link two neighbouring CdII atoms, forming extended eight-membered C2S4Cd2 tricyclic units whose geometry can be approximated by a chair conformation. The coordination polyhedron of the CdII atoms is a distorted square-pyramid. The five-membered furan ring and the benzene ring are disordered over two sets of sites with an occupancy ratio of 0.62 (8):0.38 (8).

cis-Bis(4-methyl-piperazine-1-carbo-dithio-ato-κS,S')bis-(pyridine-κN)cadmium.

In the title complex, [Cd(C6H11N2S2)2(C5H5N)2], the CdII ion is hexacoordinated by two N atoms from two pyridine ligands and by four S atoms from two dithiocarbamate ligands in a distorted octahedral geometry. The CdII ion lies on a twofold axis. The piperazine ring is in chair conformation and its least-squares plane makes a dihedral angle of 81.4 (1)° with that of the pyridine ring.

1-[(6-Chloro-pyridin-3-yl)meth-yl]imidazolidin-2-iminium chloride.

The title compound, C9H12ClN4 +·Cl−, is a natural metabolic product of imidacloprid [systematic name: (E)-1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] and was obtained by the reduction of the latter using Fe in HCl. The dihedral angle between the pyridine and imidazole rings is 62.09 (12)°. The crystal structure is stabilized by N—H⋯Cl and C—H⋯Cl interactions involving the chloride anion. The pyridine N and the chloride atoms are not involved in intermolecular interactions.

Bis(O-ethyl dithio-carbonato-κS,S')bis-(pyridine-3-carbonitrile-κN)nickel(II).

The Ni2+ ion in the title complex, [Ni(C3H5OS2)2(C6H4N2)2], is in a strongly distorted octahedral coordination environment formed by an N2S4 donor set, with the Ni2+ ion located on a centre of inversion. In the crystal, weak C—H⋯S and C—H⋯N interactions are observed.