Triterpenoids and a sterol from the stem-bark of Styrax japonica and their protein tyrosine phosphatase 1B inhibitory activities.
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.
Kwon
Joo-Hee
JH
College of Pharmacy, Catholic University of Daegu, Gyeongbuk 712-702, Korea.
Chang
Min-Jung
MJ
Seo
Hyo-Won
HW
Lee
Jeong-Hun
JH
Min
Byung-Sun
BS
Na
MinKyun
M
Kim
Jin Cheol
JC
Woo
Mi Hee
MH
Choi
Jae Sue
JS
Lee
Hyeong Kyu
HK
Bae
KiHwan
K
D004791:Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D024301:Plant Bark / Q000737:chemistry*; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors; D021241:Spectrometry, Mass, Electrospray Ionization; D013261:Sterols / Q000302:isolation & purification / Q000494:pharmacology*; D032362:Styrax / Q000737:chemistry*; D014315:Triterpenes / Q000302:isolation & purification / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D013261:Sterols; D014315:Triterpenes; D017027:Protein Tyrosine Phosphatases