Biosynthesis of Naphthyl Isoquinoline Alkaloids

The published structures of Ancistrocladus alkaloids (see Section II) show a broad variation concerning the hydrogenation degree of the isoquinoline part, the 

Naphthyl Isoquinoline Alkaloids from Triphyophyllum and Dionchophyllum Plants 

Formula (mol wt), structure Occurrence mp ( O [a]o (solvent) Methods for structural elucidation 

Isotriphyophylline (24) 33) - C24H27O3N (377) T. peltatum twigs and leaves (33) D. tholonii twigs and leaves (33) 256 (33) -22° (CHCI3) (33) Spectroscopy (33) Same dehydrogenation product as 23 (33) 

Astonishing that reduction with NaBH4 should lead only to the trans isomer 25. Formula miscalculated in Ref. 33. 

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