Formation of the morphine precursor salutaridine is catalyzed by a cytochrome P-450 enzyme in mammalian liver

Article abstract of DOI:10.1016/S0040-4039(00)79765-6

A highly regio- and stereoselective microsomal-bound cytochrome P-450 NADPH dependent enzyme has been discovered in pig liver which is responsible for the intramolecular phenol oxidative coupling of (R)-reticuline to salutaridine, thus giving rise to the morphine skeleton in mammals.