Tetrahydroprotoberberine alkaloids with dopamine and σ receptor affinity
摘要:
Two series of analogues of the tetrahydroprotoberberine (THPB) alkaloid (+/-)-stepholidine that (a) contain various alkoxy substituents at the C10 position and, (b) were de-rigidified with respect to (+/-)-stepholidine, were synthesized and evaluated for affinity at dopamine and sigma receptors in order to evaluate effects on D3 and sigma 2 receptor affinity and selectivity. Small n-alkoxy groups are best tolerated by D3 and sigma 2 receptors. Among all compounds tested, C10 methoxy and ethoxy analogues (10 and 11 respectively) displayed the highest affinity for sigma 2 receptors as well as sigma 2 versus sigma 1 selectivity and also showed the highest D3 receptor affinity. De-rigidification of stepholidine resulted in decreased affinity at all receptors evaluated; thus the tetracyclic THPB framework is advantageous for affinity at dopamine and sigma receptors. Docking of the C10 analogues at the D3 receptor, suggest that an ionic interaction between the protonated nitrogen atom and Asp110, a H-bond interaction between the C2 phenol and Ser192, a H-bond interaction between the C10 phenol and Cys181 as well as hydrophobic interactions of the aryl rings to Phe106 and Phe345, are critical for high affinity of the compounds. (C) 2016 Elsevier Ltd. All rights reserved.
An Efficient Formal Synthesis of the Human Telomerase Inhibitor (±)-γ-Rubromycin
作者:Dominea C. K. Rathwell、Sung-Hyun Yang、Kit Y. Tsang、Margaret A. Brimble
DOI:10.1002/anie.200903316
日期:2009.10.12
in the naphthazarin and isocoumarin fragments facilitates the acid‐mediated spiroketalization step to afford the key densely functionalized spiroketal (see picture; EOM=ethoxymethyl) in the formal synthesis of (±)‐γ‐rubromycin. A novel regioselective allyloxylation/Claisen rearrangement of 2‐azido‐1,4‐naphthoquinone provides access to the highly oxygenated naphthazarin fragment.
Dihydroxylation Studies of Isoquinolinones: Synthesis of the EF-Ring of Lysolipin I
作者:Dirk Menche、Maximilian J. B. Heinemann、Thomas Voigt
DOI:10.1055/a-1628-7972
日期:2022.1
Inspired by the potent polycyclic xanthone antibiotic lysolipin I, a general study on asymmetric dihydroxylation reactions of variously substituted isoquinolinones was performed. Different isoquinolinones were efficiently prepared, either by a Pomeranz–Fritsch type condensation or a Curtius rearrangement. Under a broad variety of conventional oxygenation procedures, they proved very unreactive. However
受强效多环氧杂蒽酮抗生素溶血脂 I 的启发,对不同取代的异喹啉酮的不对称二羟基化反应进行了一般性研究。通过 Pomeranz-Fritsch 型缩合或 Curtius 重排,可以有效地制备不同的异喹啉酮。在各种各样的常规氧化程序下,它们被证明是非常不活泼的。然而,通过适当取代附加的芳环或更多的强制条件,最终可以进行二羟基化,这允许合成溶脂素 I 的 EF 环。
A divergent route to 9,10-oxygenated tetrahydroprotoberberine and 8-oxoprotoberberine alkaloids: synthesis of (±)-isocorypalmine and oxypalmatine
作者:Satishkumar Gadhiya、Shashikanth Ponnala、Wayne W. Harding
DOI:10.1016/j.tet.2015.01.004
日期:2015.2
A new route which is germane to the synthesis of 9,10-oxygenated tetrahydroprotoberberines and 8-oxoprotoberberines is described. The route features the use of a diester (14) generated from reaction of dimethylmalonate with an aryl halide in the presence of n-butyllithium. The amide 17 prepared in subsequent steps is a versatile precursor for the synthesis of tetrahydroprotoberberine and 8-oxoprotoberberine