Potent quinoxaline-spaced phosphono .alpha.-amino acids of the AP-6 type as competitive NMDA antagonists: synthesis and biological evaluation
摘要:
A series of alpha-amino-3-(phosphonoalkyl)-2-quinoxalinepropanoic acids was synthesized and evaluated for NMDA receptor affinity using a[H-3]CPP binding assay. Functional antagonism of the NMDA receptor complex was evaluated in vitro using a stimulated [H-3]TCP binding assay and in vivo by employing an NMDA-induced seizure model. Some analogues also were evaluated in the [H-3]-glycine binding assay. Several compounds of the AP-6 type show potent and selective NMDA antagonistic activity both in vitro and in vivo. In particular alpha-amino-7-chloro-3-(phosphonomethyl)-2-quinoxalinepropanoic acid (1) displayed an ED50 Of 1.1 mg/kg ip in the NMDA lethality model. Noteworthy is alpha-amino-6,7-dichloro-3-(phosphonomethyl)-2-quinoxalinepropanoic acid (3) with a unique dual activity, displaying in the NMDA receptor binding assay an IC50 of 3.4 nM and in the glycine binding assay an IC50 of 0.61 muM.
A rapid and divergent access to chiral azacyclic nucleoside analogues via highly enantioselective 1,3-dipolar cycloaddition of β-nucleobase substituted acrylates
A rapid and divergent access to chiral azacyclic nucleoside analogues was developed via enantioselective 1,3-dipolar cycloaddition of β-nucleobase substituted acrylates.
Highly enantioselective 1, 3-dipolar cycloaddition of 2-arylidene-benzofuran- 3(2H)-ones with imino esters catalyzed by thiourea−quaternary ammonium salts has been developed. This reaction provides efficient construction of a range of chiral spiro[benzofuran-2,3′-pyrrolidine] in high yields (up to 99%) and with good enantioselectivities (up to 99% ee) under mild conditions.
Asymmetric construction of fluorinated imidazolidines via Cu(i)-catalyzed exo′-selective 1,3-dipolar cycloaddition of azomethine ylides with fluorinated imines
作者:Qing-Hua Li、Liang Wei、Xuan Chen、Chun-Jiang Wang
DOI:10.1039/c3cc43025a
日期:——
Expedient access to optically active fluorinated 2,4-trans-imidazolidines was successfully developed via Cu(I)-catalyzed exo'-selective 1,3-DC of azomethine ylides with fluorinated imines.
Copper(I)-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition of Azomethine Ylides with Fluorinated Imines: The Expanded Scope and Mechanism Insights
作者:Liang Wei、Qing-Hua Li、Chun-Jiang Wang
DOI:10.1021/acs.joc.8b01743
日期:2018.10.5
The mechanism of the Cu(I)/(S,Rp)-PPFOMe-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with fluorinated aldimines has been studied using labeling experiments, control experiments, and linear effect experiments, which clearly ruled out the 1,3-DC/epimerization pathways and explained the unusal exo′-selective stereochemistry. This protocol allows for the preparation of a series of highly functionalized
使用标记实验,对照实验和线性效应实验研究了Cu(I)/(S,R p)-PPFOMe催化的1,3-偶极环偶氮亚甲基与氟化亚胺的加成反应的机理,明确排除了1,3- DC /差向异构化途径和解释了此项特殊的外切' -选择性的立体化学。该方案允许以良好的产率和优异的立体选择性制备一系列高度官能化的氟化咪唑烷。而且,目前的方法已经成功地扩展到通过内含物合成具有挑战性的,带有CF 3的季立构中心的咪唑烷类化合物。在相同的反应条件下,用三氟化酮亚胺对甲亚胺烷基化物进行1,3-DC选择性合成。