20846-00-8Relevant articles and documents
Activation of propane 2-nitronate to a genotoxicant in V79-derived cell lines engineered for the expression of rat hepatic sulfotransferases
Andrae, Ulrich,Kreis, Patricia,Coughtrie, Michael W.H.,Fabel, Ulrike,Meinl, Walter,Bartsch, Ingrid,Glatt, Hansruedi
, p. 191 - 197 (1999)
2-Nitropropane (2-NP) is a genotoxic hepatocarcinogen in rats. The genotoxicity of the compound has been attributed to a sulfotransferase-mediated formation of DNA-reactive species from the anionic form of 2-NP, propane 2-nitronate (P2N). Several observations have suggested that sulfotransferases (SULTs) 1A1 and/or 1C1 may be important in the activation of P2N to a genotoxicant in rat liver, but a definite proof is lacking. In order to identify the sulfotransferase(s) of rat liver that are capable of activating P2N, we have investigated the genotoxicity of P2N in various V79-derived cell lines engineered for expression of individual forms of rat hepatic sulfotransferases. Genotoxicity was assessed by measuring the induction of DNA repair synthesis. 1-Hydroxymethylpyrene (HMP), which is metabolically activated by most sulfotransferases, served as a positive control. Neither P2N nor HMP induced DNA repair in the parental V79-MZ cells, which do not show any sulfotransferase activity. P2N was also inactive in V79-rHSTa and V79-rHST20 cells, which express specific hydroxysteroid sulfotransferases. By contrast, a clear and concentration-dependent induction of repair synthesis by P2N was observed in V79-rPST-IV and V79-rST1C1 cells, which express rat SULT1A1 and SULT1C1, respectively. HMP was genotoxic in all sulfotransferase-expressing cell lines. Acetone oxime (AO), the tautomeric form of the first reduction product of 2-NP, 2-nitrosopropane, was inactive in all cell lines. The results corroborate the essential role of sulfotransferases in the metabolic activation of P2N to genotoxic products and identify two rat sulfotransferases which are capable of catalyzing the activation step.
Electrostatic Catalysis of Proton-Transfer Reactions: Hydrogen Exchange in Chloroform and Ionization of 2-Nitropropane
Dahlberg, D. B.,Kuzemko, M. A.,Chiang, Y.,Kresge, A. J.,Powell, M. F.
, p. 5387 - 5390 (1983)
Rates of detritiation of chloroform-t catalyzed by a series of ω-trimethylammonioalkylamines, (CH3)3N+(CH2)nNH2 with n = 3-5, were measured in aqueous solution at 25 deg C, and rates of ionization of 2-nitropropane catalyzed by the same amines with n = 2-5, four additional uncharged primary amines, two aminocarboxylate ions, and ethylenediamine and its monoprotonated conjugate acid were also measured.The uncharged primary amines give a good Broensted correlation for the nitroalkane ionization, with β = 0.61 +/- 0.03; the positively charged catalysts show positive deviation from this correlation and the negatively charged catalysts show negative deviations.The ω-trimethylammonioalkylamines also give positive deviations from a previously constructed Broensted correlation for the chloroform detritiation reaction; the latter deviations are much larger than the corresponding ones for 2-nitropropane ionization, which is consistent with the greater developement and concentration of charge in the transition state of the chloroform reaction.The pattern of electrostatic effects provided by these results indicates a field rather than an inductive mechanism for transmission of the polar interaction.
Radical and Ionic Reactions of (Benzoylmethyl)mercurials
Russell, Glen A.,Kulkarni, Shekhar V.,Khanna, Rajive K.
, p. 1080 - 1086 (2007/10/02)
Photolysis of PhCOCH2HgCl or (PhCOCH2)2Hg yields benzoylmethyl radicals which can be trapped by anions such as Me2C=NO2-, RC(CO2Et)2-, RC(O-)=CH2 or by other electron-rich systems such as (RO)3P, N-methylpyrrole, enamines, or norbornene.Electron transfer from the adduct radicals to the mercurials yields PhCOCH2A from the anions A-, PhCOCH2P(O)(OR)2 from P(OR)3, and the phenacyl derivative from N-methylpyrrole or enamines.Easily oxidized anions such as PhCOCPh2- or PhC(CH3)=NO2- react with PhCOCH2* by electron transfer to yield the dimer derived from the anion.Addition of PhCOCH2* to norbornene yields a substituted 3-benzoylpropyl radical which cyclizes at the ortho position of the benzoyl group to give the α-tetralone derivative.
