Diversity-oriented synthesis of imidazo[2,1-<i>a</i>]isoquinolines
作者:Shaoyu Mai、Yixin Luo、Xianyun Huang、Zhenghao Shu、Bingnan Li、Yu Lan、Qiuling Song
DOI:10.1039/c8cc05390a
日期:——
Herein, we report an efficient and practical strategy for the synthesis of five types of imidazo[2,1-a]isoquinolines via Cp*RhIII-catalyzed [4+2] annulation of 2-arylimidazoles and α-diazoketoesters, whose structural and substituted diversity at 5- or 6-position can be precisely controlled by the α-diazoketoester coupling partners. Compared with previous reports, in this study, we merged two attractive
本文中,我们报告了通过Cp * Rh III催化的2-芳基咪唑和α-重氮酮酸酯的[4 + 2]环合反应合成五种咪唑并[ 2,1- a ]异喹啉的有效而实用的策略。可以通过α-重氮酮酸酯偶合伙伴精确控制5位或6位取代的多样性。与以前的报告相比,在这项研究中,我们通过选择合适的酯基团(–COOEt,–COO tBu或–COOiPr)或廉价的添加剂(HOAc或KOAc)。此外,通过几种生物活性化合物的简明合成和代表性药物的后期修饰,证明了这些方法的合成功效。
Sulfur/DABCO Promoted Reductive Coupling/Annulation Cascade Reaction between o-Hydroxy/Amino Nitrobenzenes and Benzaldehydes
作者:Phuong Hoang Tran、Minh-Huy Dinh Dang、Linh Ho Thuy Nguyen
DOI:10.1055/s-0039-1690823
日期:2020.6
Sulfur/DABCO was found to be an efficient reagent in promoting the reductivecoupling/annulation of o-nitrophenols or o-nitroanilines with benzaldehydes. This method represents a simple, straightforward, and green approach to the construction of benzoxazoles and benzimidazoles.
Eco-friendly highly efficient solvent free synthesis of benzimidazole derivatives over sulfonic acid functionalized graphene oxide in ambient condition
作者:Mantosh B. Swami、Arvind H. Jadhav、Sushil R. Mathpati、Hanmant G. Ghuge、Sudhakar G. Patil
DOI:10.1007/s11164-016-2745-y
日期:2017.4
(GO-HSO3) heterogeneouscatalyst was prepared at molecular level and characterized by using various modern analytic and spectroscopic methods. Using prepared heterogeneouscatalyst GO-HSO3, benzimidazolesynthesis was carried out by means of reacting diamine and aldehyde at room temperature in solvent free condition. The catalyst GO-HSO3 showed tremendous catalytic activity in selective synthesis of benzimidazole
Synthesis, antioxidant, and antimicrobial evaluation of some 2-arylbenzimidazole derivatives
作者:Binhua Zhou、Baojian Li、Wei Yi、Xianzhang Bu、Lin Ma
DOI:10.1016/j.bmcl.2013.05.004
日期:2013.7
A series of 2-arylbenzimidazole derivatives (3a-3p and 4a-4i) were synthesized and evaluated as potential antioxidant and antimicrobial agents. Their antioxidant properties were evaluated by various in vitro assays including hydroxyl radical (HO center dot) scavenging, superoxide radical anion (O-2(center dot)) scavenging, 1,1-diphenyl- 2-picrylhydrazyl (DPPH) radical scavenging, and ferric reducing antioxidant power. Results demonstrated that compounds with hydroxyl group at the 5-position of benzimidazole ring had a comparable or better antioxidant activity in comparison to standard antioxidant tert-butylhydroquinone (TBHQ). Markedly, compound 4h that showed the highest HO center dot scavenging activity (EC50 = 46 mu M) in vitro had a significant reduction of 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced intracellular oxidative stress and H2O2-induced cell death. In addition, these compounds showed moderate to good inhibitory activity against Staphylococcus aureus selectively at noncytotoxic concentrations. (C) 2013 Elsevier Ltd. All rights reserved.
Synthesis of 2-arylbenzimidazoles via microwave Suzuki–Miyaura reaction of unprotected 2-chlorobenzimidazoles
作者:Brad M. Savall、Jill R. Fontimayor
DOI:10.1016/j.tetlet.2008.09.043
日期:2008.11
A series of 2-arylbenzimidazoles were synthesized via microwave-mediated Suzuki-Miyaura coupling of 2-chloro benzimidazoles and either arylboronic acids or aryltrifluoroborate salts. The most notable aspect of the present work is that there is no need for protection of the benzimidazoles. In addition, reaction conditions were optimized to reduce homo coupling of pyridylboronic acids. (C) 2008 Elsevier Ltd. All rights reserved.