Alkaloids of the wood of Cryptocarya chinensis

Four new pavine alkaloids, (+)-eschscholtzidine-N-oxide (1), (-)-12-hydroxycrychine (2), (-)-12-hydroxy-O-methylcaryachine (3), and (-)-N-demethylcrychine (4), and four new proaporphine alkaloids, isocryprochine (5), prooxocryptochine (6), isoamuronine (7), and (+)-8,9-dihydrostepharine (8), together with nine known compounds were isolated from an ethanol extract of the wood of Cryptocarya chinensis. Their structures were elucidated by spectral analysis (NMR and MS), and the structures of 2 and 5 were confirmed by X-ray crystallography.