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Title: A Synthesis of Alstonlarsine A via Alstolucines B and F Demonstrates the Chemical Feasibility of a Proposed Biogenesis
Abstract

We offer a new biogenetic proposal for the origin of the complex alkaloid alstonlarsine A, through rearrangement of theStrychnosalkaloids alstolucines B and F. Further, we provide evidence of the chemical feasibility of this proposal in the facile conversion of synthetic alstolucines into alstonlarsine A through a short, efficient sequence ofN‐methylation, β‐elimination, and a cascade 1,7‐hydride shift/Mannich cyclization. We believe that this is the first biogenetic proposal involving the “tert‐amino effect”, a hydride‐shift‐based internal redox trigger of a Mannich cyclization. A further interesting feature of the cascade is that its stereochemical outcome most likely originates in conformational preferences during the hydride shift.

 
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NSF-PAR ID:
10385663
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
135
Issue:
4
ISSN:
0044-8249
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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