3257-49-6Relevant articles and documents
Iron(II) and Copper(I) Control the Total Regioselectivity in the Hydrobromination of Alkenes
Cruz, Daniel A.,Sinka, Victoria,De Armas, Pedro,Steingruber, Hugo Sebastian,Fernández, Israel,Martín, Víctor S.,Miranda, Pedro O.,Padrón, Juan I.
, p. 6105 - 6109 (2021/08/18)
A new method that allows the complete control of the regioselectivity of the hydrobromination reaction of alkenes is described. Herein, we report a radical procedure with TMSBr and oxygen as common reagents, where the formation of the anti-Markovnikov product occurs in the presence of parts per million amounts of the Cu(I) species and the formation of the Markovnikov product occurs in the presence of 30 mol % iron(II) bromide. Density functional theory calculations combined with Fukui's radical susceptibilities support the obtained results.
Efficacy of novel phenoxyalkyl pyridinium oximes as brain-penetrating reactivators of cholinesterase inhibited by surrogates of sarin and VX
Chambers, Janice E.,Chambers, Howard W.,Funck, Kristen E.,Meek, Edward C.,Pringle, Ronald B.,Ross, Matthew K.
, p. 154 - 159 (2016/12/06)
Pyridinium oximes are strong nucleophiles and many are effective reactivators of organophosphate-inhibited cholinesterase (ChE). However, the current oxime reactivators are ineffective at crossing the blood-brain barrier and reactivating brain ChE in the intact organism. Our laboratories have developed a series of substituted phenoxyalkyl pyridinium oximes (US patent 9,227,937 B2) with the goal of identifying reactivators effective in crossing the blood-brain barrier. The first 35 of the series were found to have similar in?vitro efficacy as reactivators of ChE inhibited by a sarin surrogate (phthalimidyl isopropyl methylphosphonate, PIMP) or a VX surrogate (nitrophenyl ethyl methylphosphonate, NEMP) in bovine brain preparations as previously observed in rat brain preparations. A number of these novel oximes have shown the ability to decrease the level of ChE inhibition in the brains of rats treated with a high sublethal dosage of either a sarin surrogate (nitrophenyl isopropyl methylphosphonate, NIMP) or the VX surrogate NEMP. Levels of reactivation at 2?h after oxime administration were up to 35% while the currently approved therapeutic, 2-PAM, yielded no reduction in brain ChE inhibition. In addition, there was evidence of attenuation of seizure-like behavior with several of the more effective novel oximes, but not 2-PAM. Therefore these novel oximes have demonstrated an ability to reactivate inhibited ChE in brain preparations from two species and in?vivo data support their ability to enter the brain and provide a therapeutic action. These novel oximes have the potential to be developed into improved antidotes for nerve agent therapy.
Fragmentations observed in the reactions of α-methoxy-γ- alkoxyalkyl iodide substrates with super-electron-donors derived from 4-DMAP and N-methylbenzimidazole
Sword, Ryan,Baldwin, Luke A.,Murphy, John A.
experimental part, p. 3560 - 3570 (2011/06/20)
Reactions of super-electron-donors (SEDs) derived from 4- dimethylaminopyridine and from N-methylbenzimidazole with α-methoxy- γ-alkoxyalkyl iodides lead to liberation of the γ-alkoxy groups as their alcohols. This is consistent with generation of alkyl radicals from the alkyl halide precursors, and trapping of these radicals by the radical-cation of the SED, followed by a heterolytic fragmentation.
