Synthesis of castanospermine

Authors

Theeraphan Machan, University of WollongongFollow
Andrew S. Davis, University of Wollongong
Boonsom Liawruangrath, Chiang Mai University
Stephen G. Pyne, University of WollongongFollow

RIS ID

25497

Publication Details

Machan, T., Davis, A. S., Liawruangrath, B. & Pyne, S. G. (2008). Synthesis of castanospermine. Tetrahedron, 64 2725-2732.

Abstract

The diastereoselective synthesis of castanospermine is described in 11 synthetic steps from L-xylose. The borono-Mannich reaction between L-xylose, allylamine and (E)-styrene boronic acid gives a tetrahydroxy amine with the desired configurations for C-6, C-7, C-8 and C-8a in the target molecule. A novel pyrrolo[1,2-c]oxazol-3-one precursor was employed to allow for the control of pi-facial diastereoselectivity in an osmium(VIII)-catalysed syn-dihydroxylation (DH) reaction. A regioselective ring-opening of the cyclic sulfate derivative of the resulting diol then secured the C-1 hydroxyl group of castanospermine with the correct configuration. A Mitsunobu cyclization then provided di-O-benzyl castanospermine and ultimately the final target alkaloid.