[Separation and resolution of four stereo-isomers of anisodamine].

Four stereo-isomers of anisodamine were obtained by two consecutive resolutions. (+) 6-Methoxy methoxy tropinone (+I) and its optical antipode (-I) could be obtained by the resolution of racemic (I) with (+) L-tartaric acid and (-) D-tartaric acid respectively. Subsequent catalytic hydrogenation of the optically active compound I, then ester exchange with methyl 2-formyl-2-phenyl acetate followed by reduction with NaBH4 and cleavage of hydroxyl protective group in acid condition, the corresponding optically active (+) IV and (-) IV were obtained. Compound (+) IV was treated with (+) dibenzoyltartaric acid and (-) IV by (-) dibenzoyltartaric acid. The epimeric salts were separated and purified by fractional crystallization from absolute alcohol. Four stereoisomers of anisodamine (6S, 2'S; 6S, 2'R; 6R, 2'R and 6R, 2'S) were thus obtained by neutralization of the corresponding salts.