1. Xia, Q.; Xiao, P. G.; Wang, L. W.; Kong, J. Zhongguo Zhongyao Zazhi 1997, 22, 515–518.
2. The roots of Phyllanthus emblica L. were collected in the Wenshan county of Yunnan province, China, and air-dried. A voucher specimen is deposited with the Herbarium of Kunming Institute of Botany, Chinese Academy of Sciences.
3. Compound 1: [α]25D +19.3 (c 0.28, CH3OH); FABMS m/z: 421 [M+H]+, 299 [M−C7H5O2+H]+, 105 [C7H5O]+, 77 [C6H5]+; anal. calcd for C21H24O9·1/2H2O: C, 58.74; H, 5.87. Found: C, 58.79; H, 5.79.
4. A solution of 1 (15 mg) in MeOH (2 ml) was treated with CH2N2/Et2O at rt. After concentrated in vacuo, the mixture was purified on a silica gel column to afford 2 (8 mg), as a yellowish powder, [α]25D +19.3 (c 0.85, CH3OH); FABMS m/z: 435[M+H]+.
5. Compound 2 (100 mg) was treated with pyridine (1 ml) and Ac2O (1 ml) at rt overnight and then subjected to a silica gel column to give 3 (15 mg) and 4 (106 mg). Compound 3: a yellowish powder, [α]24D +11.0 (c 0.20, CHCl3); 1H NMR (500 MHz, CDCl3) δ: 4.99 (s, H-1), 2.24 (br d, J=14.5 Hz, H-2a), 1.79 (dt, J=3.0, 13.0 Hz, H-2b), 2.45 (tt, J=3.0, 13.0 Hz, H-3), 2.06 (br d, J=13.0 Hz, H-4a), 1.92 (dt, J=3.5, 13.0 Hz, H-4b), 4.36 (s, H-5), 2.33 (dd, J=3.5, 14.5 Hz, H-9a), 2.08 (dd, J=3.0,14.5 Hz, H-9b), 5.29 (q, J=3.0 Hz, H-10), 2.22 (m, H-11), 4.06 (t, J=11.3 Hz, H-12a), 3.65 (dd, J=4.5,11.3 Hz, H-12b), 0.97 (d, J=7.0 Hz, H-14), 8.14 (dd, J=8.0,1.5 Hz, H-3′,7′), 7.48 (br t, J=8.0 Hz, H-4′,6′), 7.58 (tt, J=1.5, 8.0 Hz, H-5′), 3.61 (s, COOCH3), 1.98 (s, 1-OAc). Compound 4: a yellowish powder, [α]25D −2.4 (c 0.25, CHCl3); 1H and 13C data were shown in Table 1.