The
crude material was dissolved in 50mL of 100% methanol
and purified by absorption on a silica vacuum liquid
chromatography column (70 g TLC grade Merck silica
60, preconditioned with chloroform). The column was
rinsed with a gradient chloroform/methanol¼70/30 to
50/50 (vol/vol) under vacuum suction. The fractions
were analyzed by TLC showing that four fractions,
identified as A–D, contained a red band ðRf ¼ 0:205Þ
with p-anisaldehyde/H2SO4 reagent. The fractions A–D
were unified (430mL) and the solvent was distilled off by
rotaevaporation. The residual resin was extracted by
refluxing with 800mL chloroform containing 2.5% (vol/
vol) ethanol. The hot extract was filtered and stored at
0 C overnight for crystallization of OXY. Crystals were
filtered off, washed with chloroform, and dried under
vacuum (yield: 1.71 g, i.e., 0.34% of the wood weight).
Fig. 1. Chemical structure of the investigated hydroxystilbenes.
Thecrude material was dissolved in 50mL of 100% methanoland purified by absorption on a silica vacuum liquidchromatography column (70 g TLC grade Merck silica60, preconditioned with chloroform). The column wasrinsed with a gradient chloroform/methanol¼70/30 to50/50 (vol/vol) under vacuum suction. The fractionswere analyzed by TLC showing that four fractions,identified as A–D, contained a red band ðRf ¼ 0:205Þwith p-anisaldehyde/H2SO4 reagent. The fractions A–Dwere unified (430mL) and the solvent was distilled off byrotaevaporation. The residual resin was extracted byrefluxing with 800mL chloroform containing 2.5% (vol/vol) ethanol. The hot extract was filtered and stored at0 C overnight for crystallization of OXY. Crystals werefiltered off, washed with chloroform, and dried undervacuum (yield: 1.71 g, i.e., 0.34% of the wood weight).Fig. 1. Chemical structure of the investigated hydroxystilbenes.
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