Naturally occurring phyllodulcin (1) was orally administered to rats to investigate its metabolic fate. Urinary metabolites were analyzed by three-dimensional HPLC. Phyllodulcin- 3'-O-sulfate (2), phyllodulcin-3'-O-β-glucuronide (3), 2-[2-(3, 4-dihydroxyphenyl) ethyl]-6- hydroxybenzoic acid (4), and one novel bibenzyl derivative, 2-[2-(3-hydroxy-4- methoxyphenyl) ethyl]-6-hydroxybenzoic acid (5), together with thunberginol G (6) and ...