Phenol oxidation and biosynthesis. Part XVII. Investigations on the biosynthesis of sinomenine

Abstract

The biosynthesis of sinomenine in Sinomenium acutum has been investigated. In accordance with phenol coupling theory, reticuline, rather than ‘protosinomenine’ is shown to be the precursor of the alkaloid. The enantiomer of salutaridine, recently isolated and characterised under the name sinoacutine, has been demonstrated to be an efficient precursor of sinomenine. Later stages in the biosynthesis have been investigated and two apparently probable paths shown to be incorrect.

The alkaloid acutumine has been investigated briefly. It has been shown not to be derived from sinomenine isosinomenine, or sinoacutine. The chlorine in acutumine is not introduced by a working-up process but by a true process of biosynthesis.