Enantioselective total syntheses and X-ray structures of both (S)-tetrahydropalmatrubine (2) and (S)-corytenchine (3) are reported for the first time. They were both derived from (S)-N-norlaudanidine, a benzyltetrahydroisoquinoline that was synthesized with high (>95% ee) enantioselectivity using a chiral auxiliary-assisted Bischler-Napieralski cyclization/reduction approach.

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http://dx.doi.org/10.1021/np1001169DOI Listing

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