New imidazole alkaloids from Cypholophus friesianus (Urticaceae). The structures and synthesis of cypholophine and O-acetylcypholophine

Abstract

Two new imidazole alkaloids cypholophine (1a) and O-acetylcypholophine (1b), isolated from Cypholophus friesianus (family Urticaceae), have been synthesized. A non-alkaloidal constituent of Cypholophus decipiens has been identified as the previously known terpenoid lactone, loliolide (2).