(S)-Cheilanthifoline is a benzylisoquinoline alkaloid (BIA) which has been isolated from Corydalis cheilanthifolia and Argemone mexicana. It is derived from (S)-reticuline, a pivotal intermediate in the biosynthesis of numerous BIAs. (S)-cheilanthifoline is the immediate precursor of the BIA (S)-stylopine ((S)-stylopine synthase/CYP719A20), which is the precursor for the alkaloids protopine and sanguinarine.

Biosynthesis

Cheilanthifoline is produced from the benzylisoquinoline alkaloid, scoulerine, by the enzyme (S)-cheilanthifoline synthase.

Scoulerine is one of the products derived from (S)-reticuline.

Metabolism

Cheilanthifoline is the precursor to other alkaloids. For example, (S)-stylopine (also known as tetrahydrocoptisine) is produced when the enzyme (S)-stylopine synthase forms a second methylenedioxy ring: