scholarly journals Total Syntheses of the C19 Diterpenoid Alkaloids (−)-Talatisamine, (−)-Liljestrandisine, and (−)-Liljestrandinine by a Fragment Coupling Approach

Author(s):  
Alice R. Wong ◽  
Nicholas J. Fastuca ◽  
Victor W. Mak ◽  
Jeffrey K. Kerkovius ◽  
Susan M. Stevenson ◽  
...  
2021 ◽  
Author(s):  
Alice Wong ◽  
Nicholas Fastuca ◽  
Victor Mak ◽  
Jeff Kerkovius ◽  
Susan Stevenson ◽  
...  

<p>The C19 aconitine-type diterpenoid alkaloids (–)-talatisamine, (–)-liljestrandisine, and (–)-liljestrandinine have been prepared in 31, 30, and 33 steps, respectively, from phenol. The synthetic approach features a 1,2-addition/semi-pinacol rearrangement as the key fragment coupling tactic. These efforts have also resulted in a correction to the original structure assignment of (–)-liljestrandisine.</p>


2019 ◽  
Author(s):  
Maxime Jarret ◽  
Victor Turpin ◽  
Aurélien Tap ◽  
Jean-Francois Gallard ◽  
Cyrille Kouklovsky ◽  
...  

We report the enantioselective total syntheses of mavacurans alkaloids, (+)-taberdivarine H, (+)-16-hydoxymethyl-pleiocarpamine, (+)-16-epi-pleiocarpamine, and their postulated biosynthetic precursor 16-formyl-pleiocarpamine. This family of monoterpene indole alkaloids is a target of choice since some of its members are subunits of intricate bisindole alkaloids such as bipleiophylline. Inspired by the biosynthetic hypothesis, we explored an oxidative coupling approach from the geissoschizine framework to form the N1-C16 bond. Quaternization of the aliphatic nitrogen was key to achieve the oxidative coupling induced by KHMDS/I<sub>2 </sub>since<sub> </sub>it hides the nucleophilicity of the aliphatic nitrogen and locks the required cis conformation.


2017 ◽  
Vol 34 (9) ◽  
pp. 1044-1050 ◽  
Author(s):  
Xiao-Yu Liu ◽  
Yong Qin

Recent accomplishments in the total syntheses of diterpenoid alkaloids and their biosynthetically associated diterpenes have highly relied on an oxidative dearomatization/Diels–Alder cycloaddition strategy, and are highlighted in this article.


Synthesis ◽  
2019 ◽  
Vol 51 (21) ◽  
pp. 3915-3946 ◽  
Author(s):  
Christian Dank ◽  
Randy Sanichar ◽  
Ken-Loon Choo ◽  
Madeline Olsen ◽  
Mark Lautens

The diterpenoid alkaloids serve as a rich source of synthetic targets for organic chemists, due to the intriguing structure of the overlapping ring systems, along with biological activities commonly associated with compounds of this group. Fifteen total syntheses and numerous synthetic studies towards construction of ring fragments have been reported since 2010. This review article gives a brief overview of diterpenoid alkaloids and summarizes the recent synthetic efforts.1 Introduction1.1 Structural Classification and Biosynthetic Origin1.2 Structure Elucidation of the Aconitum Alkaloids2 Total Syntheses2.1 C18-Diterpenoid Alkaloids2.2 C19-Diterpenoid Alkaloids2.3 C20-Diterpenoid Alkaloids3 Strategies To Synthesize Ring Systems3.1 Radical-Based Cyclizations3.2 Ruthenium-Mediated Enyne Cycloisomerization3.3 Reductive Coupling3.4 Diels–Alder Reactions3.5 Oxidative Dearomatization/Diels–Alder Sequence3.6 Transannular Aziridation3.7 Intramolecular [5+2] Cycloaddition3.8 Miscellaneous4 Conclusion


2019 ◽  
Author(s):  
Maxime Jarret ◽  
Victor Turpin ◽  
Aurélien Tap ◽  
Jean-Francois Gallard ◽  
Cyrille Kouklovsky ◽  
...  

We report the enantioselective total syntheses of mavacurans alkaloids, (+)-taberdivarine H, (+)-16-hydoxymethyl-pleiocarpamine, (+)-16-epi-pleiocarpamine, and their postulated biosynthetic precursor 16-formyl-pleiocarpamine. This family of monoterpene indole alkaloids is a target of choice since some of its members are subunits of intricate bisindole alkaloids such as bipleiophylline. Inspired by the biosynthetic hypothesis, we explored an oxidative coupling approach from the geissoschizine framework to form the N1-C16 bond. Quaternization of the aliphatic nitrogen was key to achieve the oxidative coupling induced by KHMDS/I<sub>2 </sub>since<sub> </sub>it hides the nucleophilicity of the aliphatic nitrogen and locks the required cis conformation.


Sign in / Sign up

Export Citation Format

Share Document