Abstract
Systematic phytochemical investigation of the bark and leaves of Betula alba was independently conducted. A new cyclic diarylheptanoid glucoside (1), five diarylheptanoids (2–6), a phenylethanoid (7), a methyl salicylate glycoside (8), a dihydrobenzofuran glucoside (9), an arylbutanoid glycoside (10), two lignan glycosides (11 and 12), a flavanone glucoside (13), and a triterpene (14) were isolated from the bark of B. alba. On the other hand, two cyclic diarylheptanoids (15 and 16), five flavonoids (17–21), a phenylpropanoid (22), a phenylbutanoid glucoside (23), and a monoterpene glucoside (24) were obtained from the leaves of B. alba. The structures of the isolated compounds (1–24) were identified on the basis of one- and two-dimensional NMR spectroscopic data. Compounds 1–24 were subsequently examined for aldose reductase (AR) inhibitory activity. Compounds 14 and 17–20 moderately inhibited AR activity with IC50 values ranging from 6.6 to 34 µM.
Disclosure statement
The authors declare no conflict of interest.