Total Synthesis of (-)-Minovine

Z. Q. Yuan; H. Ishikawa; D. L. Boger

doi:10.1055/s-2005-865350

Synfacts, Table of Contents

Synfacts 2005(0): 0007-0007
DOI: 10.1055/s-2005-865350

Synthesis of Natural Products and Drugs

Total Synthesis of (-)-Minovine

Contributor(s): Philip Kocienski

Z. Q. Yuan, H. Ishikawa, D. L. Boger*
The Scripps Research Institute, La Jolla, USA
Total Synthesis of Natural (-)- and ent-(+)-Desacetoxy-6,7-dihydrovindorosine and Natural and ent-Minovine: Oxadiazole Tandem Intramolecular Diels-Alder/1,3-Dipolar Cycloaddition Reaction
Org. Lett. 2005, 7: 741-744

Abstract

Full Text

PDF Download

Key words

Diels-Alder - dipolar cycloaddition -

Significance

Three rings in the target molecule together with five stereogenic centers were created in a single operation by heating the 1,3,4-oxadiazole A in 1,2-dichlorobenzene. Three tandem pericyclic processes were involved: a Diels-Alder reaction to form B, a retro [3+2] reaction to form dipole C, and a dipolar cycloaddition to form D in 74% yield.

Comment

Natural Minovine was reported to have an [α]_D = 0. Minovine prepared from enantiopure (+)-D (chromatographic resolution) displayed remarkable solvent-dependent but concentration-independent optical rotations accounting for the observed rotation. These studies established that natural Minovine is a single enantiomer which does not racemize on heating.

Figures