A nickel(II) catalyzed asymmetric synthesis of β-hydroxy acidsfrommalonicacid and ketones was developed, revealing for the first time the synthetic utility of malonicacid in the construction of chiral carboxyl acids; importantly, the synthetic potential of this strategy was further demonstrated by the rapid construction of cephalanthrin A, phaitanthrin B, cruciferane, and rice metabolites.
Synthesis of 6-Alkynyl-6-hydroxyindoloquinazolinone Scaffolds via Copper-Catalyzed Alkynylation of Tryptanthrins
作者:Yu Guo、Ebrahim-Alkhalil M. A. Ahmed、De-Kun Ma、Jun Jiang、Hongxin Liu、Xinhua Li、Juan Li、Hong-Ping Xiao
DOI:10.1055/a-1533-1080
日期:2021.9
alkynes under mild reaction conditions. The developed method provides an array of synthetic buildingblocks of 6-alkynyl-6-hydroxyindoloquinazolinone compounds in moderate to good yields with varied functional group compatibility. Furthermore, the obtained adducts can be smoothly converted into versatile buildingblocks via hydrogenation, hydration, and further Sonogashira coupling transformations.
tryptanthrin (indolo[2,1-b]quinazoline-6,12-dione), and its analogues are found to exhibit potent antitumor and anti-MRSA activities. An efficient and convenient method has been developed for the synthesis of tryptanthrin D-ring derivatives through the reaction of substituted tryptanthrins and secondary amines in moderate to good yields. Some of the new compounds exhibited antitumor activities against the human
Switching of Enantioselectivity in the Cu-Catalyzed Asymmetric Decarboxylative Aldol Reaction of Tryptanthrin with <i>β-</i>Keto Acids: An Unexpected Counteranion Effect
作者:Fang-Fang Feng、Xue-Qi Wang、Long Sun、Chi Wai Cheung、Jing Nie、Jun-An Ma
DOI:10.1021/acs.orglett.1c01315
日期:2021.6.4
Cu-bisoxazoline-catalyzed enantioselectivedecarboxylative aldol reaction of tryptanthrin with aryl-substituted β-ketoacids is developed, providing a straightforward approach to deliver a series of phaitanthrin A analogues. Both enantiomers of the products can be obtained with good to high enantioselectivity in the presence of a single chiral ligand by simply changing the copper salts. Based on the
开发了 Cu-双恶唑啉催化的色氨酸与芳基取代的β-酮酸的对映选择性脱羧醛醇反应,提供了一种直接的方法来提供一系列的苯菊酯 A 类似物。在单一手性配体存在下,通过简单地改变铜盐,可以以良好到高的对映选择性获得产物的两种对映异构体。基于手性 Cu(II)-双恶唑啉配合物的 X 射线晶体学分析,提出了初步的立体化学模型,以解释观察到的反阴离子诱导的对映选择性转换。
Cu-Catalyzed Synthesis of Tryptanthrin Derivatives from Substituted Indoles
作者:Chen Wang、Lianpeng Zhang、Anni Ren、Ping Lu、Yanguang Wang
DOI:10.1021/ol401144m
日期:2013.6.21
A concise method for the preparation of tryptanthrins fromindoles via the copper-catalyzed aerobic oxidation is described. The reactions can be carried out under mild reaction conditions with varying functional group tolerance.