Chung Mei-Ing, Weng Jing-Ru, Wang Jih-Pyang, Teng Che-Ming, Lin Chun-Nan
School of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China.
Planta Med. 2002 Jan;68(1):25-9. doi: 10.1055/s-2002-19871.
Two new pentaoxygenated xanthones, 2,3-dihydroxy-1,6,7-trimethoxyxanthone (1) and 3,6-dihydroxy-1,5,7-trimethoxyxanthone (2) were isolated from the leaf of Hypericum geminiflorum. The antiplatelet activities of the constituents, 2,6-dimethoxy-p-benzoquinone (3), gemichalcone A (4), gemichalcone B (5), and cycloartocarpin (6), of this plant, were assessed in vitro by determining their inhibitory effects on the aggregation of washed rabbit platelets induced by various inducers. The anti-inflammatory effects of 4 and 5 were assessed in vitro by determining their inhibitory effects on the chemical mediators released from mast cells and neutrophils. Of the compounds tested, 4 exhibited the most potent inhibition of platelet aggregation induced by arachidonic acid (AA) and 4 and 5 strongly inhibited the release of beta-glucuronidase and lysozyme in formyl-Met-Leu-Phe (fMLP)-stimulated rat neutrophils.
从双花金丝桃的叶子中分离出两种新的五氧代呫吨酮,即2,3 - 二羟基 - 1,6,7 - 三甲氧基呫吨酮(1)和3,6 - 二羟基 - 1,5,7 - 三甲氧基呫吨酮(2)。通过测定该植物成分2,6 - 二甲氧基对苯醌(3)、双花查耳酮A(4)、双花查耳酮B(5)和环木菠萝素(6)对各种诱导剂诱导的洗涤兔血小板聚集的抑制作用,在体外评估了它们的抗血小板活性。通过测定4和5对肥大细胞和中性粒细胞释放的化学介质的抑制作用,在体外评估了它们的抗炎作用。在所测试的化合物中,4对花生四烯酸(AA)诱导的血小板聚集表现出最有效的抑制作用,并且4和5强烈抑制甲酰 - 甲硫氨酸 - 亮氨酸 - 苯丙氨酸(fMLP)刺激的大鼠中性粒细胞中β - 葡萄糖醛酸酶和溶菌酶的释放。