New lignan glucosides with tyrosinase inhibitory activities from exocarp of Castanea henryi Original Research Article

Three novel lignan glycosides, 1-[4-(β-glucopyranosyl (1→2)-[β-glucopyranosyl (1→6)]-β-glucopyranosyloxy)-3-methoxyphenyl]-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (1), 2,3-dihydro-2-[4-(β-glucopyranosyl (1→2)-[β-glucopyranosyl (1→6)]-β-glucopyranosyloxy)-3-methoxyphenyl]-3-(hydroxymethyl)-7-methoxy-5-benzofuranpropanol (2), 7-hydroxy-9′-β-glucopyranosyloxyl secoisolariciresinol (3) and two known lignans were isolated from exocarp of Castanea henryi. Their structures were established by spectroscopic means, and their tyrosinase inhibitory potentials were evaluated in vitro using mushroom tyrosinase.