Synthesis, Antimalarial Activity, and Molecular Modeling of New Pyrrolo[1,2-a]quinoxalines, Bispyrrolo[1,2-a]quinoxalines, Bispyrido[3,2-e]pyrrolo[1,2-a]pyrazines, and Bispyrrolo[1,2-a]thieno[3,2-e]pyrazines
摘要:
Three pyrrolo[1,2-a]quinoxalines, 15 bispyrrolo[1,2-a]quinoxalines, bispyrido[3,2-e]pyrrolo[1,2-a]pyrazines, and bispyrrolo[1,2-a]thieno[3,2-e]pyrazines were synthesized from various substituted nitroanilines or nitropyridines and tested for their in vitro activity upon the erythrocytic development of Plasmodium falciparum strains with different chloroquine-resistance status. Bispyrrolo[1,2-a]quinoxalines showed superior antimalarial. activity with respect to monopyrrolo[1,2-a]quinoxalines. The best activity was observed with bispyrrolo[1,2-a]quinoxalines linked by a bis(3-aminopropyl)piperazine. Moreover, it was observed that the presence of a methoxy group on the pyrrolo[1,2-a]quinoxaline nucleus increased the pharmacological activity. Drug effects upon beta-hematin formation were assayed and showed similar or higher inhibitory activities than CQ. A possible mechanism of interaction implicating binding of pyrroloquinoxalines to beta-hematin was supported by molecular modeling.
使用有效的钯-化合物以高收率合成了一系列新的4-碱基聚吡咯并[1,2- a ]喹喔啉衍生物,生物碱chimanine B的原始和结构类似物以及先前描述的4-烯基吡咯并[1,2- a ]喹喔啉。催化了铃木-宫浦的交叉偶联反应。测试了这些新化合物对三种利什曼原虫属物种的体外抗寄生虫活性。株。生物学结果表明,它对大麦草,墨西哥麦草和多诺氏乳杆菌的前鞭毛体形式具有活性,IC 50范围为1.2至14.7μM。在尝试调查我们的吡咯并[1,2- a]喹喔啉衍生物是一种广谱抗原生动物化合物,对一种布鲁氏锥虫菌株具有活性,还研究了W2和3D7恶性疟原虫菌株。同时,在鼠J774和人HepG2细胞系上评估了这些分子的体外细胞毒性。这些新型合成化合物的结构-活性关系在此进行了讨论。
Novel series of bis- and tris-pyrrolo[1,2-a]quinoxaline derivatives 1 were synthesized and tested for in vitro activity upon the intraerythrocytic stage of W2 and 3D7 Plasmodium falciparum strains. Biological results showed good antimalarialactivity with IC50 in the μM range. In attempting to investigate the large broad-spectrum antiprotozoal activities of these new derivatives, their properties toward
Here we describe the identification and preliminary characterization of a new class of pyrrolo(imidazo)quinoxaline hydrazones as flurescent probes for Aβ1-42 fibrils. All the newly developed compounds were able to bind amyloid fibrils formed in vitro and some of them displayed an increase of their fluorescence upon binding. When tested on brain tissue preparations presenting Aβ deposits, the described hydrazones selectively stained amyloid structures and did not display aspecific binding. The hydrazones did not show antifibrillogenic activity and electron microscopy analysis revealed that they do not interfere with fibrils structure. The described pyrrolo(imidazo)quinoxalines could be useful for studying amyloid structures in vitro. Moreover, their experimentally proven ability to cross the blood–brain barrier in mouse opens the possibility of developing these compounds as potential amyloid imaging agents for in vivo applications.
coupling 4-chloropyrrolo[1,2-a]quinoxalines with 1,3-bis(aminopropyl)piperazine or -methylamine using Xantphos as the ligand. The ferrocenic bispyrrolo[1,2-a]quinoxalines 2 were prepared by reductive amination of previously described bispyrrolo[1,2-a]quinoxalines 9 with ferrocene-carboxaldehyde, by treatment with NaHB(OAc)(3). The best results were observed with ferrocenic pyrrolo[1,2-a]quinoxalines linked
Access to quinolinones <i>via</i> DMAP-catalysed cascade reaction of 2-substituted benzoic acids with organic azides
作者:Yuan-Yuan He、Mei-Shan Zhu、Yang Gao、Xiao-Qiang Hu
DOI:10.1039/d2cc04406d
日期:——
DMAP-catalysed Curtius rearrangement and intramolecular cyclisation cascade reaction of 2-substituted aryl carboxylic acids with organicazides for the first time. This protocol features simple operation, broad scope and metal-free conditions, furnishing a broad spectrum of biologically attractive heterocycles. The synthetic virtue of this reaction was demonstrated by gram-scale synthesis and applicability toward
and straightforward approach for the synthesis of fused quinoxalinones via palladium-catalyzedcascade carbonylative cyclization of 2-heteroaryl iodobenzene and NaN3 has been achieved. The transformation might undergo cascade carbonylation, formation of acyl azide, a Curtius rearrangement, and an intramolecular cyclization sequence. The obtained heterocycle products can be easily transformed into other
通过钯催化的 2-杂芳基碘苯和 NaN 3的级联羰基环化合成稠合喹喔啉酮的简单直接的方法已经实现。该转化可能经历级联羰基化、酰基叠氮化物的形成、Curtius 重排和分子内环化序列。获得的杂环产品可以很容易地转化为其他结构多样的有价值的化合物,这证明了所开发协议的综合效用。