Narciclasine tetraacetate

However, the problem of the stereochemistry and of the absolute configuration of narciclasine has been solved through X-ray analysis and biosynthetic investigations. Thus, the biological derivation of narciclasine from vittatine 284 and the X-ray data obtained on a single crystal of narciclasine tetraacetate pointed to the stereostructure 376 for the antimitotic lactam (87, 88). 

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