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The isomer distribution of nitroarachidonate (AAN[O.sub.2]) is synthesized and demonstrates its ability to modulate inflammation. Synthesis of AAN[O.sub.2] is achieved by nitration of arachidonate treatment with sodium nitrite in acidic conditions following HPLC separation.

A complete equation of state for the molecular crystal 1,1-diamino-2,2-dinitroethlene is calculated from first principles for temperatures between 0 and 400 K, and for specific volumes from 61 to 83 [cm.sup.3]/mol. The calculated 300 K isotherm is in good agreement with the experimentally measured pressure-volume relation and it has only a very small dependence on specific volume.

A model similar to an isodesmic reaction is presented for describing, defining and calculating the interaction energies of the indirectly linked groups or atoms within one molecule, including nitro substitutes of methane, benzene and cubane. The results have proved that the so-called interaction energy is a new, quantitative and useful tool to evaluate the stabilities of nitro compounds.

A study was conducted to investigate the interaction of polypyridine nitrosyl ruthenium complexes with the DNA upon photoactivation. Two water molecules form strong hydrogen bonds with the nitro and the carboxylic oxygen atoms of two separate units of complex resulting in a dimeric unit.

The crystal structure of the high-pressure phase of hexahydro-1,3,5-trinitro-1,3,5-triazine ([gamma]-RDX) is investigated by using infrared spectroscopy and powder X-ray diffraction measurements followed by Rietveld refinements using a diamond anvil cell (DAC). The molecular structure of the [gamma] phase has displayed the same conformation as that of the alpha phase, but the torsion angles of N-N[O.sub.2] changed marginally.

Plane-wave ab initio calculations based on the density function theory (DFT) method with the ultrasoft pseudopotentials are used to study the structural and electronic properties of energetic crystal TNAD (trans-1,4,5,8-tetranitro-1,4,5,8-tetraazadecalin). The thermal expansion coefficients calculated for the crystal has shown anisotropic behavior with the largest expansion along the b axis.

PA-824 is a promising new compound for the treatment of tuberculosis that is currently undergoing human trials. Like its progenitors metronidazole and CG1-17341, PA-824 is a prodrug of the nitroimidazole class, requiring bioreductive activation of an aromatic nitro group to exert an antitubercular effect. We have confirmed that resistance to PA-824 (a nitroimidazo-oxazine) and CG1-17341 (a nitroimidazo-oxazole) is most commonly mediated by loss of a specific glucose-6-phosphate dehydrogenase (FGD1) or its deazaflavin cofactor [F.sub.420], which together provide electrons for the reductive activation of this class of molecules. Although FGD1 and [F.sub.420] are necessary for sensitivity to these compounds, they are not sufficient and require additional accessory proteins that directly interact with the nitroimidazole. To understand more proximal events in the reductive activation of PA-824, we examined mutants that were wild-type for both FGD1 and [F.sub.420] and found that, although these mutants had acquired high-level resistance to PA-824 (and another nitroimidazo-oxazine), they retained sensitivity to CG1-17341 (and a related nitroimidazo-oxazole). Microarray-based comparative genome sequencing of these mutants identified lesions in Rv3547, a conserved hypothetical protein with no known function. Complementation with intact Rv3547 fully restored sensitivity to nitroimidazo-oxazines and restored the ability of Mtb to metabolize PA-824. These results suggest that the sensitivity of Mtb to PA-824 and related compounds is mediated by a protein that is highly specific for subtle structural variations in these bicyclic nitroimidazoles. comparative genome sequencing | [F.sub.420] | nitroimidazole

An experimental electron density was determined to understand magnetic interaction pathways in a purely organic free radical, m-(ethynyl)pyridyl nitronyl nitroxide, using accurate X-ray diffraction measurements. The intermolecular contacts were characterized by a topological analysis of the experimental electron density.

Peroxymitrite reacts with 2',3',5'-tri-O-acetyl-guanosine to yield a novel compound identified as 1-(2,3,5-tri-O-acetyl-Beta-D-erythro-pentofuranosyl)-5-guanidino-4-nitroimidazole (6). This characterization was achieved using a combination of UV/vis spectroscopy and ESI-MS.

The temperature dependent regioselectivity in photosubstitution of the nitro group vs the methoxy group of triplet 4-nitroanisole by hydroxide ion in water which leads to product yields of about 80% 4-methoxyphenol and 20% 4-nitrophenol is discussed. The correct prediction of regioselectivity could be achieved by the quantum chemical calculation of the competing triplet transition-state energies, or those of the corresponding triplet [sigma]-complexes.

The synthesis by Suzuki cross-coupling methodology of oligo(arylene) molecular wires with protected thiolates at both termini and a central electron-acceptor unit (3,5-dinitrofluorenone) or an electron-donor unit [9-(1,3-dithiol-2-ylidene)fluorene] in the backbone is described. The studies have shown that thiolated molecules that possess strongly electron-withdrawing core units containing nitro groups are not suitable for controlled assembly in junctions.

A direct aza-MIRC (Michael initiated ring closure) reaction on (E,E)-1,4-dialkyl-2,3-dinitro-l,3-butadienes under very mild conditions was performed to obtain ([plusmn])-2,2'-dinitro-2,2'-biaziridines. A simple reaction with sodium iodide in d imethyl sulfoxide ( DMSO), with an unforeseen regioselective aziridine C-C cleavage was performed to achieve ring enlargement of 3,3'-bi(1,2,4-oxadiazole) derivatives.

The reaction of glyoxal-derived [alpha]-diimines with palladium acetates in nitromethane has led to cleavage of the C-N bond in nitromethane, to give palladium nitro complexes in which the [alpha]-diimine ligand is methylated.

A new method is described for high-yielding synthesis of [alpha]-amino phosphonates through three-component reaction of nitro compounds, aldehydes, or ketones and dialkyl or triaryl phosphites by using indium in dilute aqueous HCl at room temperature. The one-pot conversion consists of the reduction of nitro compounds to amines, formation of imines from amines and carbonyl compounds and hydrophosphonylation of imines.

The various mechanisms involved in the CuI/L-proline catalyzed coupling of aqueous ammonia with 2-iodoacetanilides and 2-iodophenylcarbamates are discussed. The discussed coupling is shown to be extremely helpful in the assembly of the various substituted 1H-benzimidazoles and 1,3-dihydrobenzimidazol-2-ones.

An intramolecular 1,4-dipolar cycloaddition of a cross-conjugated heteroaromatic betaine was used to develop an efficient stereocontrolled route to the isoschizozygane alkaloid core. The modified version of the method could also be used for synthesis of the hexacyclic framework of the shizozygane alkaloid ([plusmn])-strempeliopine.

The various mechanisms involved in the reduction of the aromatic nitro compounds by using several different high valent oxo-rhenium complexes are discussed. The technique used is shown to be extremely beneficial for the reduction of several other compounds.

The highly enantioselective addition of thioacetic acid to nitroalkenes is described by using a new sulfinyl urea organocatalyst. The new method is used for preparing chiral 1,2-aminothiol derivatives, as shown by the first enantioselective synthesis of the clinically used antifungal drug sulconazole.

A [beta]-tribromomethyl nitroalkanes in good to excellent yields and diastereoselectivity was prepared via addition of bromoform to conjugated nitroalkenes in the presence of Mg. The newly developed Michael adducts could also be used to carry out a one-pot high yield sythesis of the dibromides under anionic conditions via LDA mediated addition of bromoform to nitroalkenes.

A very simple and efficient method is described to perform highly chemoselective reduction of aromatic nitro compounds to corresponding amino derivatives by using Cu nanoparticles and ammonium formate. The reduction could also be carried out by wide variety of other reducible functional groups in the molecules such as Cl, I, OC[H.sub.2]Ph, NHC[H.sub.2]Ph, COR, COOR, and CN.

An efficient and scalable three-step one-pot method is described to obtain 6-methyl-5-nitroisoquinoline from inexpensive 5-nitroisoquinoline via vicarious nucleophilic substitution (VNS) as a key step. The optimized reaction conditions could be applied to synthesize other aromatic and heteroaromatic nitro compounds.

The article discusses a new approach, where in 2-nitroglycals are used as glycosyl donors for the synthesis of several different glycoconjugates. The method is shown to be extremely beneficial because of the high selectivity and yield.

Microscopic simulations are used to study the thermodynamic and chemical properties of inert nitromethane explosive on a Hugoniot curve. The Crussard curve of detonation properties is calculated.

Tropos benzophenone-like phosphoramidite ligands are described in which the chirality can be instantaneously controlled by a chiral amine. Higher enantioselectivity and catalytic activity can be obtained in the Cu catalysis, by virtue of instant chirality control in these ligands.

The dominant factors governing the impact sensitivity ([H.sub.50]) of nitrobenzenes and saturated nitro compounds are analyzed. The cross-validation results have shown the quantitative model to be stable, which might also be a useful tool for the design of high-energy-density materials.

A study demonstrates that copper-containing nitrite reductase endogenously produces its own NO from nitrite under reducing conditions. The comparison between the electron paramagnetic resonance (EPR) signals that are respectively produced from [super 14]N- versus [super 15]N-nitrite provides evidence that endogenously produced NO is a major component of the paramagnetic signal of copper-containing reducatase (NiR).

The synthesis, crystal structure, and magnetic properties of newly designed napth [2,3-d] imidazol-2-yl nitronyl nitroxide are described to examine the effects of ring extension on the crystal packing and magnetic behavior. The results conclude that space interaction between the O atoms of the nitroxide is predominant, by considering the identical magnetic data between the NH nondeuterated and deuterated samples.

Energies of optimized geometries of nitrones and their corresponding .OH adducts is calculated using density functional theory (DFT) at the B3LYP/6-31+31G**//B3LYP/6-31G* level. Calculations predict that the trans adduct formation is favored in alkoxycarbonyl nitrones, while cis adducts with intramolecular H-bonding is favored for alkoxphosphonyl nitrones.

The synthesis structure and magnetic properties of a nitronyl nitroxide-substituted 5,10-diphenyl-5,10-dihydrophenazine radical cation are mentioned. The findings of the experiment are presented.

HOF. CH3CN was reacted with various aliphatic and aromatic vicinal diamino compounds. The products were the rare, vicinal dinitro derivatives formed in excellent yields and short reaction times.

The Michael addition of primary aliphatic nitro compounds to alpha,beta-unsaturated enones, performed in aqueous media, provides the one-pot synthesis of 1,4-diketones, 1,4-diols, gama-nitroalkanols, and hydroxytetrahydrofurans, respectively, by the appropriate choice of the reaction conditions.

The synthesis and the structure of a complex having a quartet ground state with three entirely different spin carriers, namely nitronyl nitroxide (NN), o-semiquinone (o-SQ) and cupric ion are presented. The results of X-ray structural characterization suggest a substantial interaction between the two spin carriers NN and 0-SQ.

A kinetic resolution approach using BINOL [H.sub.2]/biphenol [H.sub.2] mixed La-Li heterobimetallic complexes to obtain tertiary nitroaldols in 80-97% ee is described. These nitroaldol derived from simple ketones were found to have best selectivity with 30-47% recovery yield.

A resonance Raman (RR) and X-ray absorption characterization of Mb-HNO, which yields new information on bonding within this species, is discussed. The results provided definitive evidence for the structure of Mb-HNO, which supports the structure deduced on the basis of NMR experiments and is the first structural characterization of an HNO bound to a heme protein.