The benzocphenanthridine class of substances display a variety of pharmacological properties. A large number of naturally occurring alkaloids that contain a benzocphenanthridine ring system and have a known spectrum of activity are mentioned in the literature.1, 2 Aside from fagaronine (1), the most important representative of this group of natural products, other alkaloids with extensive pharmacological potential are nitidine (2), chelerythrine (3), and sanguinarine (4; Scheme 1).3-5 The synthesis of these natural products is of great interest, because they can be isolated from plant materials only in very small amounts. Cushman et al.6 describe yields in the 0.003 to 0.07 range for the isolation of 2 from a series of zanthoxylum and fagara varieties. Compound 1 was first isolated from the root of Fagara zanthoxyloides in 1972.
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