Acta Cryst. (2006). E62, o598-o600 [ doi:10.1107/S1600536806000912 ]
Abstract: In the title optically active protoberberine derivative [systematic name: (S)-(-)-2,3-dimethoxy-5,6,13,13a-tetrahydro-8H-dibenzo[a,g]quinolizin-8-one], C19H19NO3, the key intermediate in the synthesis of enantiomerically pure (S)-(-)-O-methylbharatamine, the absolute configuration of the asymmetric centre at the 13a position has been confirmed as S by crystal structure refinement. The H atom at the asymmetric centre assumes an -orientation and occupies a pseudo-axial position relative to the central non-planar rings of the tetracyclic skeleton.
Online 13 January 2006
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