1.Longikaurin E induces apoptosis of pancreatic cancer cells via modulation of the p38 and PI3K/AKT pathways by ROS.
Cheng HB1, Bo Y, Shen WX, Ren XG, Tan JN, Jia ZR, Xu CL. Naunyn Schmiedebergs Arch Pharmacol. 2015 Jun;388(6):623-34. doi: 10.1007/s00210-015-1107-4. Epub 2015 Mar 6.
Pancreatic cancer is a devastating disease with a poor prognosis. It ranks as the fourth or fifth most common cancer in men and women and has the lowest 5-year survival rate. Therefore, there is an urgent need to develop novel therapeutic agents for pancreatic cancer. Longikaurin E (LE), which is derived from the traditional herbal medicine Rabdosia longituba, had been reported to have anti-proliferative and pro-apoptotic properties in several types of cancers. In this study, we investigated the cytotoxic properties of LE against pancreatic cancer cells and explored the mechanism behind the observed apoptosis. Pancreatic cancer cell lines cultured in the presence of LE exhibited dose- and time-dependent growth suppression by clone formation, methylthiazoltetrazolium assay, lactate dehydrogenase cytotoxicity assay, and fluorescence-activated cell sorting analysis, respectively. In addition, these culture conditions also induced the generation of cellular reactive oxygen species (ROS).
2.A unified strategy to ent-kauranoid natural products: total syntheses of (-)-trichorabdal A and (-)-longikaurin E.
Yeoman JT1, Mak VW, Reisman SE. J Am Chem Soc. 2013 Aug 14;135(32):11764-7. doi: 10.1021/ja406599a. Epub 2013 Jul 30.
The first total syntheses of (-)-trichorabdal A and (-)-longikaurin E are reported. A unified synthetic strategy is employed that relies on a Pd-mediated oxidative cyclization of a silyl ketene acetal to generate an all-carbon quaternary center and build the bicyclo[3.2.1]octane framework. These studies, taken together with our previous synthesis of (-)-maoecrystal Z, demonstrate that three architecturally distinct ent-kauranoids can be prepared from a common spirolactone intermediate.