Isosakuranetin-5-O-rutinoside: a new flavanone with antidepressant activity isolated from Salvia elegans Vahl.

Ursolic acid (1) and a new flavanone, 5-O-(6-rhamnosylglucoside)-7-hydroxy-4'-methoxyflavanone (2), were isolated from the leaves of Salvia elegans Vahl. These natural products displayed antidepressant activity in mice as determined by means of a forced swimming test (FST) evaluation. Structural elucidation was carried out by chemical derivatization (acetylation) and spectroscopic analyses, such as 1H- and 13C-NMR and two-dimensional (2-D) COSY, heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple-bond correlation (HMBC) spectroscopy experiments.