Purpurin (1,2,4-trihydroxy-9,10-anthraquinone), a natural red anthraquinone pigment in madder root (Rubia tinctorum L.), possesses antifungal activity against Candida species. Purpurin is also a specific inhibitor of adipocyte-derived leucine aminopeptidase (A-LAP) and can be developed as a new anti-angiogenic agent.

Canadine (tetrahydroberberine,THB) is an isoquinoline alkaloid (5,8,13,13a-tetrahydro-9,10-dimethoxy-6H-benzo[g]-1,3-benzodioxolo[5,6-a]quinolizine) from Corydalis tuber, it has micromolar affinity for dopamine D(2) (pK(i) = 6.08) and 5-HT(1A) (pK(i) = 5.38) receptors but moderate to no affinity for other relevant serotonin receptors (i.e., 5-HT(1B), 5-HT(1D), 5-HT(3), and 5-HT(4). Canadine enhances gastrointestinal motor function. THB, with D(2) receptor antagonist and 5-HT(1A) receptor agonist properties, has significant potential as a therapeutic for treatment of functional dyspepsia. THB is a potent inhibitor of platelet aggregation in vitro and in vivo and is a promising antithrombotic drug.