Nitroaromatic compounds

Explosives for Use at High Temperatures. Explosives that can withstand prolonged exposure to elevated temperatures without detonating find considerable use ia such appHcations as detonators for deep oil wells, space travel, and componentry for specialised appHcations. The explosives developed for this purpose are primarily nitroaromatic compounds, the most important of which are hexanitrostilbene and... 

Miscellaneous Dyes. Other classes of dyes that stiU have some importance are the stilbene dyes and the forma2an dyes. Stilbene ( es are in most cases mixtures of dyes of indeterminate constitution that are formed from the condensation of sulfonated nitroaromatic compounds ia aqueous caustic alkah either alone or with other aromatic compounds, typically arylarnines (5). The sulfonated nitrostilbene [128-42-7] (79) is the most important nitroaromatic, and the aminoa2oben2enes are the most important arylarnines. Cl Direct Orange 34 [2222-37-6] (Cl 40215-40220), the condensation product(s) of (79) and the aminoa2oben2ene [104-23-4] (80), is a typical stilbene dye. 

Aromatic nitroso compounds usually are considered to be intermediates in the hydrogenation of a nitroaromatic compound to the aromatic hydroxyl-amine or amine. However, nitroso compounds do not accumulate in these reductions, suggesting that they are reduced more easily than are nitro compounds. Catalysts effective for the nitro group should also be effective for nitroso. 

Molecular ion The mass spectra of nitroaromatic compounds are characterized by intense molecular ions. 

Two important examples of reductive metabolism of xenobiotics are the reductive dehalogenation of organohalogen compounds, and the reduction of nitroaromatic compounds. Examples of each are shown in Figure 2.13. Both types of reaction can take place in hepatic microsomal preparations at low oxygen tensions. Cytochrome P450 can catalyze both types of reduction. If a substrate is bound to P450 in the... 

Nitroaromatic compounds have been identified in diesel engine emissions (Salmeen et al. 1984), and attention has been directed particularly to 1,8- and 1,6-dinitropyrene that are mutagenic, and possibly carcinogenic (Nakagawa et al. 1983). 

Glaus M A, CG Heijman, RP Schwarzenbach, J Zeyer (1992) Reduction of nitroaromatic compounds mediated by Streptomyces sp. exudates. Appl Environ Microbiol 58 1945-1951. 

Schwarzenbach RP, R Stierliu, K Lanz, J Zeyer (1990) Quinone and iron porphyrin mediated reduction of nitroaromatic compounds in homogeneous aqueous solution. Environ. Sci. Technol. 24 1566-1574. 

Hallas LE, M Alexander (1983) Microbial transformation of nitroaromatic compounds in sewage effluent. Appl Environ Microbiol 45 1234-1241. 

Purohit V, AK Basu (2000) Mutagenicity of nitroaromatic compounds. Chem Res Toxicol 13 673-692. 

Rafii F, W Franklin, RH Hetlich, CE Cerniglia (1991) Reduction of nitroaromatic compounds by anaerobic bacteria isolated from the human gastrointestinal tract. Appl Environ Microbiol 51 962-968. 

Hartter DR (1985) The use and importance of nitroaromatic compounds in the chemical industry. In Toxicity of Nitroaromatic Compounds (Ed DE Rickert), pp. 1-13. Hemisphere Publishing Corporation, Washington, DC. 

Crawford RL (1995) The microbiology and treatment of nitroaromatic compounds. Curr Opinion Biotechnol 6 329-336. 

Servent D, C Ducrorq, Y Henry, A Guissani, M Lenfant (1991) Nitroglycerin metabolism by Phanerochaete chrysosporium evidence for nitric oxide and nitrite formation. Biochim biophys Acta 1074 320-325. Spain JC (1995a) Biodegradation of nitroaromatic compounds. Annu Rev Microbiol 49 523-555. 

Spain JC (Ed) (1995b) Biodegradation of Nitroaromatic Compounds. Plenum Press, New York. 

Alkyl 2-chloropropionates react with nitroaromatic compounds on treatment with base to give alkyl 2-(4-nitroaryl)propionates in good yield (Eq. 9.26).40... 

Even though some nitroaromatic compounds are purposefully spread in the environment as pesticides, the majority of their environmental releases are accidental. For example, in the United States alone, 5.1 tons of nitrobenzene were released in soil in 2002 [65]. The greatest known industrial releases have occurred in China in 2005, an explosion at a chemical factory resulted in the accidental release of 100 tons of benzene and nitrobenzene to the Songhua River [66]. 

An important demonstrated application of this artificial nose system is the high-speed detection of low levels of explosives and explosive-like vapors. Several sensors, based on Nile Red attached to silica microspheres, show high sensitivity to nitroaromatic compounds (NAC) within a mixture12. Different fluorescence response profiles were observed for several NAC s, such as 1,3,5-trinitrotoluene (TNT) and 1,3-dinitrobenzene (DNB), despite their similar structures. These responses were monitored at low concentrations of the NAC vapors (ca. 5 ppb) and at short vapor exposure... 

Other bacteria. Intestinal bacteria may play a critical role in the metabolic activation of certain nitroaromatic compounds in animals (119) and several reports have appeared on the metabolism of nitro PAHs by rat and human intestinal contents and microflora (120-123). Kinouchi et al. (120) found that 1-nitropyrene was reduced to 1-aminopyrene when incubated with human feces or anaerobic bacteria. More recently, Kinouchi and Ohnishi (121) isolated four nitroreductases from one of these anaerobic bacteria (Bacteroides fragilis). Each nitroreductase was capable of converting 1-nitropyrene into 1-aminopyrene, and one form catalyzed the formation of a reactive intermediate capable of binding DNA. Howard ej al. (116) confirmed the reduction of 1-nitropyrene to 1-aminopyrene by both mixed and purified cultures of intestinal bacteria. Two additional metabolites were also detected, one of which appeared to be 1-hydroxypyrene. Recently, similar experiments have demonstrated the rapid reduction of 6-nitro-BaP to 6-amino-BaP (123). 

General considerations. Nitroaromatic compounds, such as nitro-furans and nitrobenzenes are commercially important chemicals used as drugs, food additives or synthetic intermediates. Since there is widespread human exposure to these chemicals, their metabolism has been studied extensively. Nitroaromatic compounds are reduced by both hepatic cytosol and microsomes. The microsomal activity... 

A. Bronshtein, N. Aharonson, A. Turniansky, and M. Altstein, Sol-gel-based immunoaffinity chromatography application to nitroaromatic compounds. Chem. Mater. 12, 2050-2058 (2000). 

Weissmahr, KW, Haderlein SB, Schwarzenbach RP, Hany R, Nuesch R (1997) In situ spectroscopic investigations of adsorption mechanisms of nitroaromatic compounds at clay minerals. Environ Sci Technol 31 240-247... 

Rafii F, Cemiglia CE (1995) Reduction of azo dyes and nitroaromatic compounds by bacterial enzymes from the human intestinal tract. Env Health Persp 103 17-19... 

Li L, Wang J, Zhou J et al (2008) Enhancement of nitroaromatic compounds anaerobic biotransformation using a novel immobilized redox mediator prepared by electropolymerization. Bioresour Technol 99 6908-6916... 

Luckarift HR, Nadeau LJ, Spain JC (2005) Continuous synthesis of aminophe-nols from nitroaromatic compounds by combination of metal and biocatalyst. J Chem Soc Chem Commun 383-384... 

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