Computationally aided stereochemical assignment of undescribed bisabolenes from Calea urticifolia

Publication date: January 2019Source: Phytochemistry, Volume 157Author(s): Vedanjali Gogineni, Manal A. Nael, Francisco León, Marvin J. Núñez, Stephen J. CutlerAbstractCalea urticifolia (Mill.) DC. (Compositae) is a medicinal plant found in El Salvador. Calea is used in folkloric medicine as a psychoactive principle with calming effect, as well as in the treatment of diarrhea and fever. Three undescribed bisabolenes, named caleanolenes A-C, as well as, three known sesquiterpene lactones 2,3-epoxyjuanislamin, calealactone B, calein C, and the flavonoid acacetin, were isolated from the chloroform extract of the leaves of C. urticifolia. The chemical structures of the isolated compounds were determined on the basis of HRMS, IR, CD, and from 1D and 2D NMR spectroscopic studies. The absolute configurations of the caleanolenes have been partly established using GIAO NMR and ECD calculations. The isolated compounds were evaluated for cytotoxicity against the CA46 and Raji lymphoma, and the MCF7 breast cancer cell lines, with 2,3-epoxyjuanislamin showing the best activity in all cell lines (IC50 value range 2.9–12.3 μM).Graphical abstractC. urticifolia yielded three novel bisabolenes: caleanolenes A-C, and four known compounds. The isolated compounds were evaluated for cytotoxicity against CA46 and Raji lymphoma, and MCF7 breast cancer cell lines.
Source: Phytochemistry - Category: Chemistry Source Type: research