2'-(2,3-Dihydroxybenzoyloxy)-7-ketologanin: a novel iridoid glucoside from the leaves of Gentiana kurroo.

A new bitter acylated iridoid glucoside, 2'-(2,3-dihydroxybenzoyloxy)-7-ketologanin (1), has been isolated from the leaves of Gentiana kurroo. The structure of the compound was elucidated conclusively by chemical analysis, and extensive 1D and 2D NMR experiments.