The Pyrolysis and Photolysis of the Protopine Type Alkaloid N-Oxides. The Synthesis of the Secoberbines and Benzo[c]phenanthridines

The pyrolysis of the N-oxides of the protopine-type alkaloids afforded three products, one of which was converted to the naturally occurring secoberbines.The photolysis of the N-oxides of the protopines supplied the benzo[c]phenanthridines as well as the one of the pyrolysis products.