Shan, HuiWilson, William K.Castillo, Dorianne A.Matsuda, Seiichi P.T.2015-11-092015-11-092015Shan, Hui, Wilson, William K., Castillo, Dorianne A., et al.. "Are Isoursenol and γ-Amyrin Rare Triterpenes in Nature or Simply Overlooked by Usual Analytical Methods?." <i>Organic Letters,</i> 17, no. 16 (2015) American Chemical Society: 3986-3989. http://dx.doi.org/10.1021/acs.orglett.5b01851.https://hdl.handle.net/1911/82031Among pentacyclic triterpenes commonly found in plants, γ-amyrin and isoursenol are seldom reported and considered rare in nature. It was hypothesized that these triterpenes are instead routinely overlooked due to inadequate spectral characterization. γ-Amyrin was prepared by HCOOH isomerization of α-amyrin, and isoursenol was isolated from products of a heterologously expressed oxidosqualene cyclase. With precise NMR and GC-MS data, a metabolomics strategy was used to identify isoursenol and γ-amyrin in a wide range of plants.engACS Editors' Choice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.Journal articlehttp://dx.doi.org/10.1021/acs.orglett.5b01851