Synthesis of the Pyrano[3,2-a]carbazole Alkaloids Koenine, Koenimbine, Koenigine, Koenigicine, and Structural Reassignment of Mukonicine
摘要:
Using the palladium(II)-catalyzed oxidative cyclization of a diarylamine and the annulation of a dimethylpyran ring by Lewis acid promoted reaction with prenal as key steps, the total syntheses of the 6-oxygenated pyrano[3,2-a]carbazole alkaloids koenine and koenimbine, and of the 6,7-dioxygenated pyrano[3,2-a]carbazole alkaloids koenigine and koenigicine (koenimbidine, koenidine) were achieved. Moreover, these studies led to an improved synthetic route to the 2,6-dioxygenated carbazole alkaloid glycozolidol. Mukonicine, originally published as 6,8-dimethoxypyrano[3,2-a]carbazole, was found to be identical with koenigicine.
Transition Metals in Organic Synthesis, Part 91:¹ Palladium-Catalyzed Approach to 2,6-Dioxygenated Carbazole Alkaloids - First Total Synthesis of the Phytoalexin Carbalexin C
作者:Hans-Joachim Knölker、Marika Schmidt
DOI:10.1055/s-0029-1217810
日期:2009.9
The palladium(0)-catalyzed C-N bond formation and palladium(II)-catalyzed oxidative cyclization provide an efficient route to a series of 2,6-dioxygenated carbazole alkaloids including the first totalsynthesis of the phytoalexin carbalexin C.
钯 (0) 催化的 CN 键形成和钯 (II) 催化的氧化环化为一系列 2,6-二氧化咔唑生物碱提供了有效途径,包括植物抗毒素卡巴莱辛 C 的首次全合成。
Total Syntheses of Clausenawallines A and E
作者:Cameron B. Berlin、Hanna F. Roenfanz、Madeleine Salwen、Sai Nehete、Marisa C. Kozlowski
DOI:10.1021/acs.orglett.4c01352
日期:2024.6.28
The first totalsyntheses of glycoborinine, clausenawalline A, and clausenawalline E were achieved. The key step employed a vanadium-catalyzed oxidative coupling of two hydroxycarbazole monomers. High-throughput experimentation was used to identify conditions favoring selective heterocoupling of these monomers that possess similar redox potentials. A combination of a vanadium catalyst and 4-acetamido-TEMPO
首次实现了糖硼蛋白、黄皮蛋白 A 和黄皮蛋白 E 的全合成。关键步骤采用钒催化的两个羟基咔唑单体的氧化偶联。高通量实验用于确定有利于这些具有相似氧化还原电位的单体选择性杂偶联的条件。相对于单独的钒催化剂,钒催化剂和4-乙酰氨基-TEMPO的组合大大提高了交叉选择性。发现了选择性形成同二聚体黄皮蛋白A或异二聚体黄皮蛋白E作为主要产物的条件。
PREVENTION AND TREATMENT OF INFLAMMATORY CONDITIONS
申请人:GLYCOREGIMMUNE, INC.
公开号:US20160158258A1
公开(公告)日:2016-06-09
In accordance with some embodiments herein, methods and compositions for prevention and treatment of inflammatory conditions are provided. In some embodiments, compositions comprising NKT-2 activators, for example miltefosine are provided. In some embodiments, the compositions further comprise sulfatide and/or a RAR agonist. In some embodiments, the compositions comprise activators of Type II NKT cells, and/or inhibitors of Type I NKT cells.