| Abstract
| - Three novel triterpenes, 3,4-seco-olean-12-ene-3,28-dioic acid (4), 3α-hydroxyolean-11-en-28,13β-olide (5),and 3α-hydroxyoleane-11:13(18)-dien-28-oic acid (6), were isolated from the aerial parts of the Argentineanshrub, Junellia tridens. Another five compoundsoleanolic (1), oleanonic (2), and epioleanolic acids (3),all biosynthetically related to the three new oleananes, and epibetulinic acid (7) and sitosterol (8)werealso isolated. Structures were elucidated primarily by 1D and 2D NMR and mass spectrometry, and allprotons and carbons of the three novel compounds were fully assigned by NMR. We report the minimuminhibitory concentrations of these compounds against Mycobacterium tuberculosis and conclude that theyare responsible for antitubercular activity originally observed in the crude plant extract. LC-MS data isprovided on the occurrence of triterpenes 1−6 in six other species of Junellia.
|
