抗氧化剂由于其许多健康益处而已成为人们广泛研究的主题。在这项工作中,合成了一系列新型的羟基酪醇和香豆素共轭物,并对其体外自由基清除,毒性和抗氧化机理进行了评估。在DPPH自由基和ABTS +自由基阳离子清除试验中,所有目标化合物14a–t均表现出比BHT,羟基酪醇和香豆素更好的自由基清除活性。结构-活性关系研究表明,香豆素环上羟基的数量和位置对于良好的抗氧化能力至关重要。此外,最有前途的化合物14q在正常的WI-38和GES细胞中,溶血试验显示的毒性比BHT弱,抗增殖作用较弱,并且H 2 O 2诱导的HepG2细胞活力增强。另外,14q降低了HepG2细胞的凋亡百分比,减少了ROS的产生和LDH的释放,并改善了H 2 O 2处理的HepG2细胞中的GSH和SOD水平。最后,在甲醇溶液中,14q比羟基酪醇具有更高的稳定性。这些结果表明,羟基酪醇和香豆素的结合物显示出更好的抗氧化能力,并且是发现新型潜在抗氧化剂的有效方法。
Sonochemistry as a General Procedure for the Synthesis of Coumarins, Including Multigram Synthesis
作者:Ligia da Silveira Pinto、Marcus de Souza
DOI:10.1055/s-0036-1590201
日期:2017.6
the compounds obtained using the classical procedures. This study describes a general procedure for the synthesis of different coumarins via sonochemistry using active methylene compounds and 2-hydroxybenzaldehydes or resorcinol. The application of sonochemistry for the synthesis of these compounds was also very effective on a multigram scale with a higher yield, higher amount of crystalline compound
An unexpected cascade reaction of 3-hydroxyoxindoles with coumarin-3-carboxylates to construct 2,3-dihydrobenzofuran spirooxindoles
作者:Kuan Zhang、Huabin Han、Lele Wang、Ziying Zhang、Qilin Wang、Wenjing Zhang、Zhanwei Bu
DOI:10.1039/c9cc07114h
日期:——
An unexpected Michael addition-inspired ring-opening/closure cascade reaction of 3-hydroxyoxindoles with coumarin-3-carboxylates was developed to access new dihydrobenzofuran or dihydrobenzothiophene spirooxindoles in 68–98% yields. This reaction not only provides an expedient and convenient method to assemble dihydrobenzofuran spirooxindoles, but also establishes a new reaction mode of coumarin-3-carboxylates
environmentally friendly procedure was developed for the Knoevenagel condensation of aromatic aldehydes with diethylmalonate in the presence of FeCl3 and N-fluorobenzenesulfonimide as a source of electrophilic fluorine under solvent-free conditions. The scope of the reaction was explored using commerciallyavailable substrates. The reaction with substituted salicylaldehydes afforded the corresponding coumarin derivatives
Access to Highly Strained Tricyclic Ketals Derived from Coumarins
作者:Sravan K. Jonnalagadda、Bader I. Huwaimel、Shirisha Jonnalagadda、Jered C. Garrison、Paul C. Trippier
DOI:10.1021/acs.joc.2c00018
日期:2022.3.18
Synthesis of highly strained fused substituted dihydrobenzopyran cyclopropyl lactones derived fromcoumarin carboxylates are reported. The substrate scope tolerates a variety of 6- and 8-substituents on the coumarin ring. Substitution at the 5- or 7-position is resistant to tricyclic lactone formation except with 7-methyl substitution. Benzamide-containing coumarins afford the tricyclic ketal. A plausible
The first highly enantioselective construction of chiral cyclopropa[c]coumarins was described. Using commercially available (bis)cinchona alkaloid (DHQ)2PYR as the chiral Lewis base catalyst, together with Cs2CO3 as the achiral base, the reaction of a series of coumarin-3-carboxylate and 3-benzoyl coumarins with tert-butyl 2-bromoacetate could give rise to the corresponding cyclopropa[c]coumarins bearing
描述了手性环丙烷[ c ]香豆素的第一个高度对映选择性的结构。使用市售的(bis)金鸡纳生物碱(DHQ)2 PYR作为手性Lewis碱催化剂,以及Cs 2 CO 3作为非手性碱,一系列香豆素3-羧酸盐和3-苯甲酰基香豆素与叔丁基的反应- 2-溴乙酸丁酯可产生相应的带有三个连续手性立体中心的环丙烷[ c ]香豆素,分别在83-93%ee和90-97%ee处。建议该反应通过原位产生的内铵盐中间体进行。