*3.3. Extraction and Isolation*

The processed slices of rhizomes (2 kg) of *A. macrocephala* were powdered and extracted with methanol (10 L × 3 times) using ultrasonic extraction for 1 hour for each cycle. After the solvent was evaporated under reduced pressure, a total of 206.8 g of crude extract was obtained. The obtained extract was suspended in water (3 L) and successively partitioned with hexane (3 L × 3 times) and EtOAc (3 L × 3 times) to yield 44.4 g and 44.0 g partition fractions, respectively, after removal of solvents in vacuo. The hexane fraction (44.0 g) was subjected to a silica gel column (CC) (820 g, 10 × 80 cm) for chromatographic fractionation, eluting with a hexane-CHCl3 solvent system by stepwise increasing the polarity. The fractions were collected and combined based on TLC analysis to afford 18 fractions (Fr.1–18). Fr.5 (77.4 mg) was chromatographed on a Sephadex LH-20 column (45 g, 2 × 80 cm), eluted with CHCl3-MeOH (2.5:1) to yield compound **1** (12.1 mg). Fr.4 (77.1 mg) was first separated on a Biotage chromatographic system (SNAP KP-Sil 100 g, eluting with hexane-CH2Cl2 solvent system in increasing CH2Cl2 concentration from 15% to 80%), then purified by Sephadex LH-20 (45 g, 2 × 80 cm, eluting with CHCl3-MeOH 2:1) and silica gel column chromatography (CC) (9.25 g, 1.5× 40 cm, stepwise eluting with hexane-CH2Cl2) to give **2** (6.2 mg). Fr.8 (239.8 mg) was chromatographed on a silica gel column (120 g, 4 × 80 cm) eluted with MeOH-CHCl3 (1:1), the targeted fraction was further purified using a Sephadex LH-20 column (45 g, 2 × 80 cm), eluting with CHCl3-MeOH while gradually increasing the polarity, then further purified on a silica gel column (8.9 g, 2 × 40 cm) eluting with hexane-CH2Cl2 to yield **3** (13.5 mg). Fr.15 (4.20 g) was first chromatographed on a silica gel column (120g, 4× 80 cm) eluting with hexane-EtOAc in increasing polarity, and then further purified on a Sephadex LH-20 column (45 g, 2 × 80 cm) eluting with CHCl3-MeOH (2:1) to yield **4** (7.4 mg). Fr.10 (297.1 mg) was treated similarly to that of Fr. 4 to obtain **5** (9.6 mg).
