Cytotoxicities of Xanthones and Cinnamate Esters from Hypericum hookerianum - Wilairat, Rujida; Manosroi, Jiradej; Manosroi, Aranya; Kijjoa, Anake; Nascimento, Maria São José; Pinto, Madalena; Silva, Artur M S; Eaton, Graham; Herz, Werner (Planta Medica, 2005)