Dinitrophenol compounds

Because dinitrophenolic compounds have been known to be cataractogenic in humans, attempts have been made to a find a suitable animal model to study this phenomenon (Spencer et al. 1948). Corneal opacity and cataracts were not observed in rats fed diets providing doses in the range of 1-25 mg/kg/day for 77-182 days. However, cataract formation was observed in ducklings fed a diet of 1,200 ppm DNOC for 1-2 days (doses in mg/kg/day were not reported). In addition, administration of a single oral dose of DNOC in the range of 2.48-59.45 mg/kg to chickens produced cataracts within 1-5 hours (Buschke 1947). The cataract formation was considered related to interference with oxidative phosphorylation. 

Berhanu T, Liu J-F, Romero R, Megersa N, and Jonsson jA. Determination of trace levels of dinitrophenolic compounds in environmental water samples using hollow flber supported liquid membrane extraction and high performance liquid chromatography. 

Dinitrophenols are used as fungicides, herbicides, or insecticides. The fungicidal, herbicidal, or insecticidal properties depend on minor differences in the chemical structures of the different dinitrophenol compounds. Several dinitrophenol compounds have more than one pesticidal use. The pesticidal use of one dinitrophenol, dinoseb, was eliminated in the United States in 1986. There has recently been a voluntary cancellation of all US product registrations for the fungicide/miticide Dinocap. 

Dinitrophenol compounds can enter the body through inhalation, oral, or dermal routes of exposure. 

Berhanu et al. [200] developed a hollow fiber-SLM extraction method for the liquid chromatographic determination of dinitrophenolic compounds at ppt levels in environmental water samples. 

Figure 13.15 Chromatograms obtained by on-line ti ace enrichment of 50 ml of Ebro river water with and without the addition of different volumes of 10% Na2S03 solution for every 100 ml of sample (a) blank with the addition of 1000 p.1 of sulfite (b) spiked with 4 p.g 1 of the analytes and 1000 p.1 of sulfite (c) spiked with 4 p.g 1 of the analytes and 500 p.1 of sulfite (d) spiked with 4 p.g 1 of the analytes without sulfite. Peak identification is as follows 1, oxamyl 2, methomyl 3, phenol 4, 4-niti ophenol 5, 2,4-dinitrophenol 6, 2-chlorophenol 7, bentazone 8, simazine 9, MCPA 10, atrazine. Reprinted from Journal of Chromatography, A 803, N. Masque et ai, New chemically modified polymeric resin for solid-phase extraction of pesticides and phenolic compounds from water , pp. 147-155, copyright 1998, with permission from Elsevier Science.

Calculations on the 4-aminobenzenediazonium ion were also carried out by Alcock et al. (1980a) using ab initio and MINDO/3 techniques. They came to the conclusion that both methods have poor predictive value for the geometry of an ion of such complexity. However, two other semiempirical methods, namely MNDO (Dewar and Thiel, 1977) and AM-1 (Dewar et al., 1985), were applied with better results to a similar, but even more complex, zwitterionic diazo compound, 2-diazonio-4,6-dinitrophenolate, by Lowe-Ma et al. (1988 see 4.4 in Sec. 4.2). 

The action of uncouplers is to dissociate oxidation in the respiratory chain from phosphorylation. These compounds are toxic in vivo, causing respiration to become uncontrolled, since the rate is no longer limited by the concentration of ADP or Pj. The uncoupler that has been used most frequently is 2,4-dinitrophenol, but other compounds act in a similar manner. The antibiotic oligomycin completely blocks oxidation and phosphorylation by acting on a step in phosphorylation (Figures 12-7 and 12-8). 

In this chapter, the voltammetric study of local anesthetics (procaine and related compounds) [14—16], antihistamines (doxylamine and related compounds) [17,22], and uncouplers (2,4-dinitrophenol and related compounds) [18] at nitrobenzene (NB]Uwater (W) and 1,2-dichloroethane (DCE)-water (W) interfaces is discussed. Potential step voltammetry (chronoamperometry) or normal pulse voltammetry (NPV) and potential sweep voltammetry or cyclic voltammetry (CV) have been employed. Theoretical equations of the half-wave potential vs. pH diagram are derived and applied to interpret the midpoint potential or half-wave potential vs. pH plots to evaluate physicochemical properties, including the partition coefficients and dissociation constants of the drugs. Voltammetric study of the kinetics of protonation of base (procaine) in aqueous solution is also discussed. Finally, application to structure-activity relationship and mode of action study will be discussed briefly. 

Interaction in THF gives 2,4-dinitrophenol and ammonia, and on one occasion a violent detonation occurred potassium dinitrophenoxide may have been involved. See Sodium 2,4-dinitrophenoxide See other n-o compounds, polynitroaryl compounds... 

See entry 2-ARYLIDENEAMINO-4,6-DINITROPHENOL SALTS See Other POLYNITROARYL COMPOUNDS... 

Hydroxy-l,2,4-thiadiazoles are acidic compounds that are generally more acidic than nitrophenol but less acidic than 2,4-dinitrophenol. 

Shortly after Perkin had produced the first commercially successful dyestuff, a discovery was made which led to what is now the dominant chemical class of dyestuffs, the azo dyes. This development stemmed from the work of Peter Griess, who in 1858 passed nitrous fumes (which correspond to the formula N203) into a cold alcoholic solution of 2-aminO 4,6 dinitrophenol (picramic acid) and isolated a cationic product, the properties of which showed it to be a member of a new class of compounds [1]. Griess extended his investigations to other primary aromatic amines and showed his reaction to be generally applicable. He named the products diazo compounds and the reaction came to be known as the diazotisation reaction. This reaction can be represented most simply by Scheme 4.1, in which HX stands for a strong monobasic acid and Ar is any aromatic or heteroaromatic nucleus. 

The first commercial sulphur dye was discovered accidentally in 1873 by Croissant and BretonniSre who heated lignin-containing organic waste, such as sawdust, with sodium polysulphide at about 300 °C the product was sold under the name Cachou de Laval [52]. Even today an equivalent dye (Cl Sulphur Brown 1) is derived from lignin sulphonate, which is readily available from waste liquors from wood pulp manufacture. The real pioneer of sulphur dyes was Vidal, the first chemist to obtain dyes of this type from specific organic compounds. In particular, Sulphur Black T (Cl Sulphur Black 1) was made from 2,4-dinitrophenol in 1899. At the turn of the century many of the intermediates available were subjected to sulphurisation (thionation), that is, treatment with sulphur, sodium sulphide or sodium polysulphide to introduce sulphur linkages. 

Cl Sulphur Black 1, which is produced from the relatively simple intermediate 2,4-dinitrophenol and aqueous sodium polysulphide. A similar product (Cl Sulphur Black 2) is obtained from a mixture of 2,4-dinitrophenol and either picric acid (6.148 X = N02) or picramic acid (6.148 X = NH2). A black dye possessing superior fastness to chlorine when on the fibre (Cl Sulphur Black 11) can be made from the naphthalene intermediate 6.149 by heating it in a solution of sodium polysulphide in butanol. An equivalent reaction using the carbazole intermediate 6.150 gives rise to the reddish blue Cl Vat Blue 43 (Hydron blue). This important compound, which also possesses superior fastness properties, is classified as a sulphurised vat dye because it is normally applied from an alkaline sodium dithionite bath. Interestingly, inclusion of copper(II) sulphate in the sulphurisation of intermediate 6.150 leads to the formation of the bluish black Cl Sulphur Black 4. 

By further nitration with more concentrated acid o- and p-nitro-phenols are converted into the same 2 4-dinitrophenol, and finally into picric acid. Polynitro-derivatives of benzene, such as picric acid and trinitrotoluene, can be caused to explode by detonation with mercury fulminate or lead azide. (The formulae of these two compounds should be written.) They are endothermic, i.e. the oxygen of the nitro-group can oxidise carbon and hydrogen within the molecule and heat is liberated. This intramolecular combustion is rather considerable in the case of picric acid, which is decomposed in accordance with the equation ... 

Titanium ions can also he used as redox catalysts for the indirect cathodic reduction of nitro compounds (417). The electroreduction is carried out in an H20-H2S04/Ti(S04)2-(Pb/Cu) system at 45 80°C under 5 20Am . Nitrobenzene, dinitrobenzene, nitrotoluene, 2,4-dinitrotoluene, 2-nitro-m-xylene, nitro-phenol, 2,4-dinitrophenol, nitrophenetole, o-nitroanisole, 4-nitrochlorotoluene, ni-trobenzenesulfonic acid, and 4,4 -dinitro-stilbene-2,2 -disulfonic acid can all be reduced by this procedure to the corresponding amino compounds (418) in good yields (Scheme 146) [513-516]. Tin... 

Ortho eliminations find widespread application in the structure elucidation of aromatic nitro compounds, e.g., nitroanilines, [200] dinitrophenols, [213] trini-troaromatic explosives, [214] and nitrophenyl-methanesulfonamides. [199] (Scheme 6.75 reproduced from Ref. [199] with permission. IM Publications 1997) ... 

Photolytic. Low et al. (1991) reported that nitro-containing compounds (e.g., 2,4-dinitrophenol) degrade via UV light in the presence of titanium dioxide yielding ammonium, carbonate, and nitrate ions. By analogy, 2,4-dinitrotoluene should degrade forming identical ions. 

The function of an immuno-electrode [28] containing a model antibody (Concanavalin A) fixed in a polymeric film on a platinum electrode is probably based on other effects than those utilized in ISEs. Immuno-electrodes suitable for direct determination of antibodies were prepared by fixing a conjugate of an ionophore and an immunogen (for example the compound of dibenzo-18-crown-6 with dinitrophenol) in a PVC membrane. This system responded to the antibody against dinitrophenol [52, 53]. 

To test the first hypothesis, solutions of 3,5-dinitroanisole and hydroxide ions were flashed and the absorption spectra at different time intervals after excitation were compared. The absorption ( max 400-410 nm) that remains after all time-dependent absorptions have decayed can be shown to be due to 3,5-dinitrophenolate anion, the photosubstitution product of 3,5-dinitroanisole with hydroxide ion. When the absorption band of the 550-570 nm species is subtracted from the spectrum of the solution immediately after the flash, there remains an absorption at 400-410 nm, which can also be ascribed to 3,5-dinitrophenolate anion. The quantity of this photoproduct does not increase during the decay of the 550-570 nm species. Therefore the 550-570 nm species cannot be intermediate in the aromatic photosubstitution reaction of 3,5-dinitroanisole with hydroxide ion to yield 3,5-dinitrophenolate. Repetition of the experiment with a variety of nucleophiles on this and other aromatic compounds yielded invariably the same result nucleophilic aromatic photosubstitution is, in all cases studied, completed within the flash duration (about 20jLts) of our classical flash apparatus. 

The effect is magnified considerably if there are nitro groups both ortho and para, so that the pATa for 2,4-dinitrophenol is 4.1. A third nitro group, as in 2,4,6-trinitrophenol, confers even more acidity, and this compound has pATa 0.4, making it a strong acid. This is reflected in its common name, picric acid. 

Very little information is available about the nature of urinary metabolites of 1,3-DNB in humans. In a study that evaluated 1,3-DNB urinary metabolites after a single dermal exposure, amino and nitro metabolites were grouped together and reported as a single value relative to the level of 2,4-dinitrophenol as a standard (Ishihara et al. 1976). Amino and nitro metabolites may be derived from a variety of nitroaromatic compounds thus, they are not specific for 1,3-DNB. 

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