75685-48-2Relevant academic research and scientific papers
Total syntheses of (±)-gephyrotoxin and (±)-perhydrogephyrotoxin
Shirokane, Kenji,Tanaka, Yuya,Yoritate, Makoto,Takayama, Nobuaki,Sato, Takaaki,Chida, Noritaka
, p. 522 - 537 (2015/06/17)
This article describes the full details of our total syntheses of gephyrotoxin and perhydrogephyrotoxin. Our central strategy toward the total synthesis is based on the use of an N-methoxy group as a reactivity control element. The N-methoxyamide group enabled unique transformations, involving i) the direct coupling reaction of the N-methoxyamide with an aldehyde, and ii) the amide-selective reductive allylation. These reactions were never accomplished without the assistance of the N-methoxy group. The amide-selective reductive allylation of the N-methoxyamide was especially practical, and excluded a number of extra steps including protecting group manipulations and redox reactions in the total syntheses.
Total synthesis of (±)-gephyrotoxin by amide-selective reductive nucleophilic addition
Shirokane, Kenji,Wada, Takamasa,Yoritate, Makoto,Minamikawa, Ryo,Takayama, Nobuaki,Sato, Takaaki,Chida, Noritaka
supporting information, p. 512 - 516 (2014/01/23)
A chemoselective approach for the total synthesis of (±)- gephyrotoxin has been developed. The key to success was the utilization of N-methoxyamides, which enabled the direct coupling of the amide with an aldehyde and selective reductive nucleophilic addition to the amide in the presence of a variety of sensitive and electrophilic functional groups, such as a methyl ester. This chemoselective approach minimized the use of protecting-group manipulations and redox reactions, which resulted in the most concise and efficient total synthesis of (±)-gephyrotoxin described to date. Aim for selectivity: A chemoselective approach that utilizes N-methoxyamides has been developed for the total synthesis of (±)-gephyrotoxin. The N-methoxy group enabled the direct coupling of the amide with an aldehyde and amide-selective reductive allylation in the presence of a more electrophilic methyl ester, which resulted in the most concise and efficient total synthesis of (±)-gephyrotoxin described to date.
Importance of allylic interactions and stereoelectronic effects in dictating the steric course of the reaction of iminium ions with nucleophiles. An efficient total synthesis of (±) gephyrotoxin
Overman,Lesuisse,Hashimoto
, p. 5373 - 5379 (2007/10/02)
A stereocontrolled total synthesis of (±)-gephyrotoxin in 15 steps and 6.5% overall yield from benzyl trans-1,3-butadiene-1-carbamate is described. A key step is reduction of octahydroquinoline 27 from the more hindered concave α face to provide decahydroquinoline 28. This unusual transformation results from the interplay of allylic (A1,2) steric interactions and stereoelectronic effects.
