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Benzofuroxan (Benzo[1,2-c]1,2,5-oxadiazole N-oxide) Derivatives as Potential Energetic Materials: Studies on Their Synthesis and Properties

Šarlauskas J., Anusevičius Z., Misiunas A.

Central European Journal of Energetic Materials

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2012

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Vol. 9, nr 4

365-386

EN

The objective of this work was to prepare benzofuroxan derivatives as new, dense, potentially energetic materials and to investigate their properties, with the main focus being on 5,6-dinitrobenzofuroxan (5,6-DNBF). 5,6-DNBF was prepared by a 3-step reaction sequence: a) 1-azido-3-nitrobenzene was synthesized by diazotation of 3-nitroaniline with sodium nitrite and subsequent reaction with sodium azide in acetic/sulfuric mixed acids; b) it was nitrated with HNO3/H2SO4 to 1-azido-2,4,5-trinitrobenzene; c) thermal cyclization of the latter compound in a polar solvent gave the desired 5,6-DNBF (m.p. 177 °C). It was fully characterized by UV/VIS, FT-IR and NMR spectroscopy, mass spectrometry and single crystal X-ray diffraction. The density of the compound (X-ray) was found to be comparatively high (1.88 g/cm3), and to be superior to the previously known, isomeric energetic material ? 4,6-dinitrobenzofuroxan (4,6-DNBF) (1.76 g/cm3). Furthermore, the synthesis of some other benzofuroxan derivatives, potentially interesting as high energy, density materials (HEDMs), has been carried out. The densities of the compounds obtained were calculated using ACD Labs software (version 4.0). Based on the results obtained, it could be concluded that 5,6-DNBF is one of the densest nitro derivatives of the benzofuroxan series, comparable to CL-14, CL-17, CL-18, and thus could have potential applications as an HEDM.

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Investigation on the Electrochemistry and Cytotoxicity of Organic Nitrates and Nitroamines

Šarlauskas J., Krikštopaitis K., Miliukiene V., Čenas N., Anusevičius Z., Šaikunas A.

Central European Journal of Energetic Materials

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2011

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Vol. 8, nr 1

15-24

EN

Laboratory scale quantities of a series of organic nitrates and nitroamines were obtained by nitration with dinitrogen pentoxide in dichloromethane medium. Twenty seven synthesized compounds were explored by voltammetry methods and their cytotoxicity for mice splenocytes was evaluated. N.N'-dinitropiperazine, DINA and hexandiol-1,6-dinitrate were determined as some of the most toxic compounds. Several compounds having non-planar cyclic, bicyclic or cage structures (IHN, TNAD, DINGU, TEX) were found as less toxic, possibly due to poorer penetration through the cell membrane.

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Reduction of Nitroaromatic Explosives by Oxygen-Insensitive NAD(P)H:Nitroreductases: Implications for their Cytotoxicity and Biodegradation

Misevičiene L., Nivinskas H., Anusevičius Z., Čenas N., Nemeikaite-Čeniene A., Maldutis E., Harris R. J., Scrutton N. S.

Central European Journal of Energetic Materials

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2006

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Vol. 3, nr 4

89-101

EN

Nitroaromatic explosives are toxic and mutagenic to humans and other mammalian species. The first step(s) in the biodegradation/bioremediation of the explosive residues in soil or groundwater is their reduction by bacterial oxygeninsensitive nitroreductases to the relatively stable metabolites. Here we analyze the quantitative structure-activity relationships in the reduction of nitroaromatic explosives and model nitroaromatic compounds by mammalian DT-diaphorase (NQO1) and Enterobacter cloacae NAD(P)H:nitroreductase (NR), which performs the four-electron reduction of nitrogroups to corresponding hydroxylamines, and by Enterobacter cloacae PB2 NADPH: pentaerythritol tetranitrate reductase (PETNR), which performs nitroreduction and reduction of benzene ring with the formation of hydride-Meisenheimer adducts. Our data show that in all the cases the reduction rate of nitroaromatics mainly depends on the energetics of the charge transfer.