Leontopodic acid—a novel highly substituted glucaric acid derivative from Edelweiss (Leontopodium alpinum Cass.) and its antioxidative and DNA protecting properties

Leontopodic acid—a novel full substituted hexaric acid derivative, was isolated from the aerial parts of Edelweiss (Leontopodium alpinum Cass.) as one of the major compounds. The complex structure of leontopodic acid-2-[(3S)-3-hydroxybutanoate]-3,4,5-tris-[(2E)-3-(3,4-dihydroxyphenyl)-2-propenoate]-d-glucaric acid—was elucidated by mass spectrometry, 1D- and 2D NMR spectroscopy and HPLC monitored transesterification. Leontopodic acid exhibited pronounced antioxidative effects in the Briggs-Rauscher (BR) model [(r.a.c.)m 3.4±0.5] and the trolox equivalent antioxidant capacity (TEAC) method (TEAC value of 1.53±0.11). The antioxidative properties of this compound were confirmed by the 3D method, an in vitro assay evaluating DNA protection against oxidative damage (IC50: 1.89 μM).