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Asymmetric synthetic access to the hetisine alkaloids: total synthesis of (+)-nominine.

ABSTRACT: A dual cycloaddition strategy for the synthesis of the hetisine alkaloids has been developed, illustrated by a concise asymmetric total synthesis of (+)-nominine (7). The approach relies on an early-stage intramolecular 1,3-dipolar cycloaddition of a 4-oxido-isoquinolinium betaine dipole with an ene-nitrile dipolarophile. Subsequent late-stage pyrrolidine-induced dienamine isomerization/Diels-Alder cascade allows for rapid construction of the carbon--nitrogen polycyclic skeleton within this class of C(20)-diterpenoid alkaloids.

SUBMITTER: Peese KM

PROVIDER: S-EPMC2648811 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

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Asymmetric synthetic access to the hetisine alkaloids: total synthesis of (+)-nominine.

Peese Kevin M KM Gin David Y DY

Chemistry (Weinheim an der Bergstrasse, Germany) 20080101 5

A dual cycloaddition strategy for the synthesis of the hetisine alkaloids has been developed, illustrated by a concise asymmetric total synthesis of (+)-nominine (7). The approach relies on an early-stage intramolecular 1,3-dipolar cycloaddition of a 4-oxido-isoquinolinium betaine dipole with an ene-nitrile dipolarophile. Subsequent late-stage pyrrolidine-induced dienamine isomerization/Diels-Alder cascade allows for rapid construction of the carbon--nitrogen polycyclic skeleton within this clas ...[more]

PMID: 18046691

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