| 摘要 |
NEW MATERIAL:A compound of the formula (A is beta,D-glucosyl; R1 and R2 are each H or p-hydroxyphenyl). EXAMPLE:(-)-2R-5,7-Di(beta-D-glucosyl)-naringenin. USE:An antiallergic agent. PREPARATION:Firstly, a plant such as Asiasrum sieboldi is heated, using a mixed solvent such as water plus ethanol, to 0 deg.C-up to the boiling point of said solvent and extracted under reflux, and the resulting extract solution is suspended in water followed by carrying out a partitioning extraction using a low-polar solvent such as benzene. From the resultant water-soluble fraction, an extract solution is obtained using a solvent such as ethyl acetate and then purified to obtain a fraction containing the objective compound of the formula. Thence, this fraction is recrystallized or powdered from its solvent (e.g. water, methanol) solution. |
