Abstract

Three new phenolic compounds (4-hydroxy-2-methoxyphenyl-6-O-syringoyl-β-D-glucopyranoside, 2-hydroxy-4-methoxyphenyl-6-O-syringoyl-β-D-glucopyranoside, and 4-hydroxymethyl-2-methoxyphenyl-6-O-syringoyl-β-D-glucopyranoside) and 15 known phenolic compounds (two phenyl glucoside esters, five lignans, three diarylheptanoids and five simple aldehydes or ketones) were isolated from the secondary xylem of mature Betula pendula Roth. The compounds were identified on the basis of their NMR (1D and 2D) and mass spectral data. In total, 23 phenolic extractives present in the sapwood of two winter-dormant B. pendula trees felled at different growing sites (rich in nutrients and scarce in nutrients) were quantified by GC. Their amounts were mostly low, 0.01–0.18 mg g⁻¹ of dry wood. Total amounts of the phenolic extractives isolated were 1.2 mg g⁻¹ of dry wood (5.6% of the total methanol-soluble extractives) in the tree felled at the site rich in nutrients, and 1.9 mg g^–1 of dry wood (10% of the total methanol-soluble extractives) in the tree felled at the site scarce in nutrients.