The crystal structure of a methanol-water solvate of leurosine methiodide,
(leurosine-CH3)I-+(-). 3CH(3)OH . 2H(2)O (C47H59IN4O9. 3CH(3)OH . 2H(2)O),
is described. The piperidine ring of the upper part of the molecule adopts
a sofa conformation. an intramolecular hydrogen bond between the tertiary N
and the hydroxyl group of the vindoline moiety of the molecule is present.