Confirmation of the structure of (3S)-3-hydroxyquinine: synthesis and X-ray crystal structure of its 9-aceto analogue.

3(S)-3-Hydroxyquinine (2) has been separated from its epimeric mixture at C-3 by conversion into the 9-aceto analogue followed by chromatography. The molecular structure of the acetate was determined through single-crystal X-ray analysis, and this confirms the structure of (3S)-3-hydroxyquinine (2), the major metabolite of quinine (1).