Two new constituents from Rheum sublanceolatum.

The chemical investigation of Rheum sublanceolatum has led to the isolation of two new constituents, the structures of which were identified on the basis of physical and spectroscopic analysis as 2-acetyl-3-methyl-6,8-dihydroxy-2,3,4,4-tetrahydronaphthalene-1-one-6-O-β-d-glucopyranoside (1) and 2,5-dimethyl-7-hydroxychromone-7-O-β-d-(6′-O-galloyl)-glucopyranoside (2).