Acylated iridoid glucoside and xanthones from Canscora lucidissima: Their structures and ferroptosis inhibitory activity.

Phytochemical study on the whole plants of a Gentianaceous medicinal plant, Canscora lucidissima, gave one new acylated iridoid glucoside, canscorin A (1), and two new xanthone glycosides (2 and 3) together with 17 known compounds including five xanthones, eight xanthone glycosides, two benzophenone glucosides, caffeic acid, and loganic acid. Canscorin A (1) was assigned as a loganic acid derivative having a hydroxyterephthalic acid moiety by spectroscopic analysis together with chemical evidence, while 2 and 3 were elucidated to be a rutinosylxanthone and a glucosylxanthone, respectively. The absolute configurations of the sugar moieties of 2 and 3 were determined by HPLC analysis. The isolated compounds were evaluated for their inhibitory activities against erastin-induced ferroptosis on human hepatoma Hep3B cells and LPS-stimulated IL-1ß production from murine microglial cells.