Kwon Joo-Hee, Chang Min-Jung, Seo Hyo-Won, Lee Jeong-Hun, Min Byung-Sun, Na MinKyun, Kim Jin Cheol, Woo Mi Hee, Choi Jae Sue, Lee Hyeong Kyu, Bae KiHwan
College of Pharmacy, Catholic University of Daegu, Gyeongbuk 712-702, Korea.
Phytother Res. 2008 Oct;22(10):1303-6. doi: 10.1002/ptr.2484.
Five pentacyclic triterpenoids (1-5) and a sterol (6) were isolated from the stem-bark of Styrax japonica. The six compounds, 1-6, were determined to be 3beta-acetoxy-28-hydroxyolean-12-ene (1), 3beta-acetoxyolean-12-en-28-acid (2), 3beta-acetoxyolean-12-en-28-aldehyde (3), 3beta-acetoxy-17beta-hydroxy-28-norolean-12-ene (4), taraxerol (5) and stigmasterol (6), respectively, by spectroscopic means, including the 2D-NMR technique. Compound 4 is a newly discovered natural compound. The protein tyrosine phosphatase 1B (PTP1B) inhibitory activities of the isolated compounds (1-6) were determined in vitro. Among the isolated compounds, 3beta-acetoxyolean-12-en-28-acid (2) and 3beta-acetoxyolean-12-en-28-aldehyde (3) had the most potent inhibitory PTP1B activity, with IC50 values of 7.8 and 9.3 microm, respectively.
从日本安息香的茎皮中分离出了五种五环三萜类化合物（1 - 5）和一种甾醇（6）。通过包括二维核磁共振技术在内的光谱手段，确定这六种化合物1 - 6分别为3β - 乙酰氧基 - 28 - 羟基齐墩果 - 12 - 烯（1）、3β - 乙酰氧基齐墩果 - 12 - 烯 - 28 - 酸（2）、3β - 乙酰氧基齐墩果 - 12 - 烯 - 28 - 醛（3）、3β - 乙酰氧基 - 17β - 羟基 - 28 - 降齐墩果 - 12 - 烯（4）、蒲公英赛醇（5）和豆甾醇（6）。化合物4是一种新发现的天然化合物。在体外测定了分离出的化合物（1 - 6）对蛋白酪氨酸磷酸酶1B（PTP1B）的抑制活性。在分离出的化合物中，3β - 乙酰氧基齐墩果 - 12 - 烯 - 28 - 酸（2）和3β - 乙酰氧基齐墩果 - 12 - 烯 - 28 - 醛（3）具有最强的PTP1B抑制活性，IC50值分别为7.8和9.3微摩尔。
