17079-24-2Relevant articles and documents
Oxidative damage of proline residues by nitrate radicals (NO3): A kinetic and product study
Nathanael, Joses G.,Nuske, Madison R.,Richter, Annika,White, Jonathan M.,Wille, Uta
supporting information, p. 6949 - 6957 (2020/10/02)
Tertiary amides, such as in N-acylated proline or N-methyl glycine residues, react rapidly with nitrate radicals (NO3) with absolute rate coefficients in the range of 4-7 × 108 M-1 s-1 in acetonitrile. The major pathway proceeds through oxidative electron transfer (ET) at nitrogen, whereas hydrogen abstraction is only a minor contributor under these conditions. However, steric hindrance at the amide, for example by alkyl side chains at the α-carbon, lowers the rate coefficient by up to 75%, indicating that NO3-induced oxidation of amide bonds proceeds through initial formation of a charge transfer complex. Furthermore, the rate of oxidative damage of proline and N-methyl glycine is significantly influenced by its position in a peptide. Thus, neighbouring peptide bonds, particularly in the N-direction, reduce the electron density at the tertiary amide, which slows down the rate of ET by up to one order of magnitude. The results from these model studies suggest that the susceptibility of proline residues in peptides to radical-induced oxidative damage should be considerably reduced, compared with the single amino acid.
Photoinduced, Copper-Catalyzed Decarboxylative C-N Coupling to Generate Protected Amines: An Alternative to the Curtius Rearrangement
Zhao, Wei,Wurz, Ryan P.,Peters, Jonas C.,Fu, Gregory C.
supporting information, p. 12153 - 12156 (2017/09/12)
The Curtius rearrangement is a classic, powerful method for converting carboxylic acids into protected amines, but its widespread use is impeded by safety issues (the need to handle azides). We have developed an alternative to the Curtius rearrangement that employs a copper catalyst in combination with blue-LED irradiation to achieve the decarboxylative coupling of aliphatic carboxylic acid derivatives (specifically, readily available N-hydroxyphthalimide esters) to afford protected amines under mild conditions. This C-N bond-forming process is compatible with a wide array of functional groups, including an alcohol, aldehyde, epoxide, indole, nitroalkane, and sulfide. Control reactions and mechanistic studies are consistent with the hypothesis that copper species are engaged in both the photochemistry and the key bond-forming step, which occurs through out-of-cage coupling of an alkyl radical.
Task specific onium salts (TSOSs) as efficient soluble supports for Zard radical addition to olefins
Verron, Julien,Joerger, Jean-Michel,Pucheault, Mathieu,Vaultier, Michel
, p. 4055 - 4058 (2008/02/03)
Task specific onium salts (TSOSs), that is, functionalised ammonium salts, have been used as soluble supports to carry out intermolecular radical additions of xanthates to olefins and functional group interconversions. This methodology provides results by
Radical cyanocarbonylation using alkyl allyl sulfone precursors
Kim, Sangmo,Cho, Chang Ho,Kim, Sunggak,Uenoyama, Yoshitaka,Ryu, Ilhyong
, p. 3160 - 3162 (2007/10/03)
Acyl cyanides have been prepared by the three-component coupling reactions comprised of alkyl allyl sulfones, carbon monoxide, and p-tolylsulfonyl cyanide under tin-free radical reaction conditions. Georg Thieme Verlag Stuttgart.
New ω-phthalimidoperoxyalkanoic acids in decontamination. Destruction of some toxic organophosphorus and organosulfur pollutants
Lion,Da Conceicao,Delmas,Magnaud
, p. 1182 - 1184 (2007/10/03)
Chemical decontamination of toxic compounds (chemical warfare agents and/or insecticides) is of increasing importance. In this study, we report the use of ω-phthalimidoperoxyalkanoic acids 2 in the destruction of paraoxon (O,O-diethyl-O-para-nitrophenylphosphate), a well-known insecticide, and 2-chloro-2′-phenyldiethyl sulfide (a half mustard). We show that while all the peroxyacids used in this series allow the destruction of toxic compounds, the length n of the alkanoic side chain is important to the choice of the optimal industrial compound, which is 2d (n = 5).
