We report a Michael-type cyanation reaction of coumarins by using CO2 as a catalyst. The delivery of the nucleophilic cyanide was realized by catalytic amounts of CO2, which forms cyanoformate and bicarbonate in the presence of water. Under ambient conditions, CO2-catalyzed reactions afforded high chemo- and diastereoselectivity of beta-nitrile carbonyls, whereas only low reactivities were observed under argon or N-2. Computational and experimental data suggest the catalytic role of CO2, which functions as a Lewis acid, and a protecting group to mask the reactivity of the product, suppressing byproducts and polymerization. The utility of this convenient method was demonstrated by preparing biologically relevant heterocyclic compounds with ease.
Facile one-pot synthetic access to libraries of diversely substituted 3-aryl (Alkyl)-coumarins using ionic liquid (IL) or conventional base/solvent, and an IL-mediated approach to novel coumarin-bearing diaryl-ethynes
摘要:
The in-situ formed carbonylimidazole derivatives of Ar(alkyl)-CH2COOH react at r.t. with substituted salicylaldehydes in [BMIM][PF6] or [BMIM] [BEd as solvent, and [PAIM][NTf (2)] as basic-IL to produce libraries of 3-aryl(alkyl)coumarins. Whereas these reactions can also be performed with similar efficiency in THF by employing DBU, the IL approach offers easier work-up and recycling of the IL solvent. An IL-mediated approach to the synthesis of novel coumarin-bearing diaryl-ethynes by the Sonogshira reaction is also reported, and the potential for recycling/reuse of the IL solvent is shown. (C) 2020 Elsevier Ltd. All rights reserved.
MAO Inhibitory Activity of 2-Arylbenzofurans versus 3-Arylcoumarins: Synthesis, in vitro Study, and Docking Calculations
作者:Giulio Ferino、Enzo Cadoni、Maria João Matos、Elias Quezada、Eugenio Uriarte、Lourdes Santana、Santiago Vilar、Nicholas P. Tatonetti、Matilde Yáñez、Dolores Viña、Carmen Picciau、Silvia Serra、Giovanna Delogu
DOI:10.1002/cmdc.201300048
日期:2013.6
Monoamine oxidase (MAO) is an important drug target for the treatment of neurological disorders. Several 3‐arylcoumarin derivatives were previously described as interesting selective MAO‐B inhibitors. Preserving the trans‐stilbene structure, a series of 2‐arylbenzofuran and corresponding 3‐arylcoumarin derivatives were synthesized and evaluated as inhibitors of both MAO isoforms, MAO‐A and MAO‐B. In general
单胺氧化酶(MAO)是治疗神经系统疾病的重要药物靶标。以前有几种3-芳基香豆素衍生物被描述为有趣的选择性MAO-B抑制剂。保留了反式二苯乙烯结构,合成了一系列的2-芳基苯并呋喃衍生物和相应的3-芳基香豆素衍生物,并将其评估为MAO-A和MAO-B的抑制剂。通常,发现两种类型的衍生物都是选择性的MAO-B抑制剂,IC 50值在纳摩尔至微摩尔范围内。5-硝基-2-(4-甲氧基苯基)苯并呋喃(8)是苯并呋喃系列中活性最高的化合物,具有MAO-B选择性和可逆抑制作用(IC 50 = 140 n M)。具有与化合物8相同的取代模式的3-(4'-甲氧基苯基)-6-硝基香豆素(15)被发现是香豆素系列中活性最高的MAO-B抑制剂(IC 50 = 3 n M) 。但是,3-苯基香豆素14的活性在相同范围内(IC 50 = 6 n M),可逆,并且选择性也比化合物15高出几倍。将最具活性的化合物对接到MAO
Ph3P/I2-Mediated Synthesis of 3-Aryl-Substituted and 3,4-Disubstituted Coumarins
Ph3P/I2–Et3N-mediated one-pot two-step esterification–cyclization toward 3-aryl coumarins and 3-aryl-4-methylcoumarins is reported. The reaction of a variety of aryl acetic acids containing steric or reactive group with 2-hydroxybenzaldehydes or 2′-hydroxyacetophenone proceeded smoothly at room temperature to afford the corresponding products in good to excellent yields using inexpensive and readily
An ultrasound-assisted one-pot acylation/cyclization reaction between N-acylbenzotriazoles and 2-hydroxybenzaldehydes has been developed for the synthesis of substituted 3-arylcoumarins. Using ultrasound not only allows rapid and clean conversion but also simplifies experimental setup and parallel workup leading to rapid generation of 3-arylcoumarin libraries under mild, solvent-free, and chromatography-free