Isolation and purification of FR900359
Dried leaves of A. crenata were extracted three times with methanol (MeOH). The extract was fractionated by vacuum liquid chromatography over RP18 material using gradient elution from MeOH:H2O (3/7) to 100% MeOH. The MeOH fraction was subsequently separated on Sephadex LH-20 with MeOH as eluent. Reversed phase HPLC separation of the FR containing fraction (column: YMC C18 Hydrosphere, 250 × 4.6 mm, 3 μm; MeOH:H2O (8:2), 0.7 ml min−1) yielded pure FR (retention time 24 min). The previous commercial name for FR was UBO-QIC.