通过将1,4-萘醌醇与各种脂肪酸酯化,合成了26种新颖的萘醌脂族酯。由1-羟基-2-萘甲酸分九步制备1,4-萘醌醇,收率很高。24种新颖的合成萘醌酯类化合物显示出显着的抗疟活性,IC 50值在0.03−16.63μM的范围内。脂族链的长度和丙基链上C-2'取代基的存在影响活性。有趣的是,化合物31和37显示出非常好的抗疟活性,并且对正常的Vero细胞无毒,并且31(> 1990.38)和37(1825.94)的PTI值非常好。两个都图31和图37显示了对恶性疟原虫3D7 cyt bc 1的有效抑制作用,而对大鼠cyt bc 1没有抑制作用。他们显示了IC 50值在纳摩尔范围内,通过在Q o位点每个cyt bc 1单体结合了一种分子抑制剂,可以完全抑制cyt bc 1。
Studies on the oxidative cyclization of 3-hydroxyalkyl-1,2,4-trialkoxynaphthalenes and synthetic application for the biologically active natural compound rhinacanthone
The oxidative intramolecular cyclization of 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes was investigated. A series of 1,2-naphthoquinone fused cyclic ethers were synthesized directly from 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes by exposure to diammonium cerium (IV) nitrate. To understand the reaction mechanism, the intramolecular cyclization of 3-hydroxyalkyl-naphthoquinones that were formed as reaction intermediates was also examined. The results suggested that the reaction proceeds by a stepwise oxidation-cyclization mechanism. Using this methodology, five-step synthesis of rhinacanthone was achieved with high yield. (C) 2013 Elsevier Ltd. All rights reserved.