The Conversion of an Aporhoeadane to Allocryptopine

The benzazepinoisoindole 6, commonly referred to as Schopf Base VI, is prepared from commercially available jS-hydrastine, or by zinc in acetic acid reduction of berberinephenolbetaine. It can more conveniently be called an aporhoeadane derivative where the aporhoeadane nucleus is defined as in structure 5, the numbering system corresponding to that for the rhoeadines. 

Treatment of allocryptopine with cyanogen bromide in tetrahydrofuran results in cleavage of the N-7 to C-8 bond and formation of an A -cyano derivative.  

The above fully substantiated result should be compared with the older report outlined below in which A -demethylation was apparently accomplished.  

Through the use of labeled precursors, the sequence (H-)-reticuline- ( —)-scoulerine - ( —)-cheilanthifoline - ( —)-stylopine (— )-stylopine N- 

Allocryptopine (thalictrimine) is a strong myocontractile agent in mice, and is apparently less toxic than the indole alkaloid brevicolline. The pharmacology of protopines and other alkaloids of the Papaveraceae has been thoroughly covered up to 1972 in Ref. 11. 

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