Journal of the American Chemical Society

Asymmetric synthesis of epicylindrospermopsin via intramolecular nitrone cycloaddition. Assignment of absolute configuration

JD White, JD Hansen

Index: White, James D.; Hansen, Joshua D. Journal of the American Chemical Society, 2002 , vol. 124, # 18 p. 4950 - 4951

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Citation Number: 31

Abstract

A synthesis of (-)-epicylindrospermopsin (2) was completed that establishes its absolute configuration and corroborates the corrected structural assignment previously made to this toxin by Weinreb et al. The hydroxylamine 3, prepared from 4-bromobenzyloxyacetaldehyde , was condensed with aldehyde 4, obtained in nine steps from (R)-methionine, to give nitrone 16. Intramolecular cycloaddition of 16 proceeded stereoselectively to yield the ...