CONFIGURATION AND TOTAL ASSIGNMENT OF THE H-1-NMR AND C-13-NMR SPECTRA OF THE ALKALOID HOLSTIINE

The alkaloid holstiine [2] was reisolated from Strychnos henningsii and subjected to a total structural assignment through the concerted application of a number of two-dimensional nmr techniques that included COSY, HC-COSY, HOHAHA, NOESY, and proton-detected long-range heteronuclear chemical shift correlation (HMBC). The revised structure of holstiine proposed by Bisset et al. was rigorously confirmed by these methods. Unequivocal assignments of the1H- andl3C-nmr spectra of holstiine are reported. The stereochemistry of the 23-hydroxyl group is finally established as α on the basis of NOESY data. © 1990, American Chemical Society. All rights reserved.