Aldose Reductase Inhibitors from the Leaves of Salix hulteni

From the n-BuOH soluble fraction of the leaves of Salix hulteni, six compounds were isolated as aldose reductase inhibitors. On the basis of spectral data, these compounds were identified as diosmetin-7-O-beta-D-glucoside (1), isoquercitrin (2), diosmetin-7-O-beta-D-xylosyl-(1 -> 6)-beta-D-glucoside (3), aromadendrin-3-O-beta-D-glucoside (4), astragalin (5), and p-hydroxyacetophenone glucoside (6). All of the isolates were evaluated in vitro for inhibitory activity against the aldose reductase. Of these, compounds 1-5 exhibited inhibitory activity against aldose reductase with IC50 values ranging 1.4 to 5.8 mu M.