The first isolation of an acridone alkaloid from poncirus trifoliata

Poncirus trifoliata (L.) Raf. (Rutaceae) is the original plant of the traditional Chinese medicine “Gou Ju,” which has been used for treating pain, stomach ache, hysteroptosis, stagnant blood, and as a detoxicant of wine poisoning (1). The presence of an essential oil, coumarins, and flavonoids in this plant has been reported (2-9). However, no alkaloidal component has been detected in this plant. In the course of our studies on the isolation of the acridone alkaloids in the Rutaceae, we have reinvestigated the constituents of this plant and identified the acridone alkaloid, 5-hydroxynoracronycine, in the root bark. This is the first example of the isolation of an acridone alkaloid from the genus Poncirus. Coumarins, poncitrin (dentatin), nordentatin, and marmesin, were also identified.