C-S coupling with nitro group as leaving group via simple inorganic salt catalysis
摘要:
An efficient and practical synthetic protocol to synthesize nonsymmetrical aryl thioethers by nucleophilic aromatic substitution (SNAr) reaction of nitroarenes by thiols with potassium phosphate as the catalyst is described. Various moderate to strong electron-withdrawing functional groups are tolerated by the system to provide thioethers in a good to excellent yields. We also showed that the present method allows access to 3 drug examples in a short reaction time. Finally, mechanistic studies suggest that the reaction may form the classic Meisenheimer complex through a two-step addition elimination mechanism. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.
The formation of C–S bonds using cheap, stable and odorless sulfonylchlorides and widely sourced and less toxic alcohols with the assistance of ADDP is reported. This method is suitable for a broad substrate scope and tolerates a broad range of functional groups. Additionally, our protocol provides a green and convenient methylating method utilizing methanol or methanol-d4 and allows trideuteromethylthiolation
Sulfanylphthalonitrile analogues as selective and potent inhibitors of monoamine oxidase B
作者:Mietha M. Van der Walt、Gisella Terre’Blanche、Anna C.U. Lourens、Anél Petzer、Jacobus P. Petzer
DOI:10.1016/j.bmcl.2012.10.070
日期:2012.12
It has recently been reported that nitrile containing compounds frequently act as potent monoamine oxidase B (MAO-B) inhibitors. Modelling studies suggest that this high potency inhibition may rely, at least in part, on polar interactions between nitrile functional groups and polar moieties within the MAO-B substrate cavity. In an attempt to identify potent and selective inhibitors of MAO-B and to contribute to the known structure-activity relationships of MAO inhibition by nitrile containing compounds, the present study examined the MAO inhibitory properties of series of novel sulfanylphthalonitriles and sulfanylbenzonitriles. The results document that the evaluated compounds are potent and selective MAO-B inhibitors with most homologues possessing IC50 values in the nanomolar range. In general, the sulfanylphthalonitriles exhibited higher binding affinities for MAO-B than the corresponding sulfanylbenzonitrile homologues. Among the compounds evaluated, 4-[(4-bromobenzyl)sulfanyl]phthalonitrile is a particularly promising inhibitor since it displayed a high degree of selectivity (8720-fold) for MAO-B over MAO-A, and potent MAO-B inhibition (IC50 = 0.025 mu M). Based on these observations, this structure may serve as a lead for the development of therapies for neurodegenerative disorders such as Parkinson's disease. (C) 2012 Elsevier Ltd. All rights reserved.
Organophosphorus-Catalyzed “Dual-Substrate Deoxygenation” Strategy for C–S Bond Formation from Sulfonyl Chlorides and Alcohols/Acids