1971•Chemical and Pharmaceutical BulletinOpen access

Utilization of Protopine and Related Alkaloids. IV. Transformation of Protopine and Protoberberine Alkaloid to Benzo [c] phenan-thridine Alkaloid

Masayuki Onda, Kyoko Yonezawa, Kaoru Abe

Abstract

Anhydroprotopine and anhydromethylberberine were photocyclized to yield 5, 6, 11, 12-tetrahydrobenzo [c] phenanthridine derivatives, which were derived via two steps to sanguinarine and chelerythrine, respectively, in good yield. 5, 6, 11, 12-Tetrahydrobenzo [c]-phenanthridine derivative resulted from the initial photoproduct via rearrangement, which was trapped with dimethyl acetylenedicarboxylate as 4b, 12-etheno-compound.

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Key concepts: Protopine, Phenanthridine, Sanguinarine, Chelerythrine, Alkaloid, Chemistry, Derivative (finance), Stereochemistry