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References
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]25 +19.3 (c 0.85, CH3OH); FABMS m/z:
D
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
1
column to give 3 (15 mg) and 4 (106 mg). Compound 3: a yellowish powder, [α]24 +11.0 (c 0.20, CHCl3); H NMR
D
(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-30,70), 7.48 (br t, J=8.0 Hz, H-40,60), 7.58 (tt, J=1.5, 8.0 Hz,
H-50), 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.
6. Kupchan, S. M.; LaVoie, E. J.; Branfman, A. R.; Fei, B. Y.; Bright, W. M.; Bryan. R. F. J. Am. Chem. Soc. 1977, 99,
3199–3201.
7. Pettit, G. R.; Cragg, G. M.; Suffness, M. I.; Gust, D.; Boettner, F. E.; Williams, M.; Saenz-Renauld, J. A.; Brown, P.; Schmidt,
J. M.; Ellis, P. D. J. Org. Chem. 1984, 49, 4258–4266.
8. (a) A solution of 1 (100 mg) in MeOH:H2O (2:3, 5 ml) was treated with KMnO4 (25 mg) and NaIO4 (80 mg) at rt for 5 h, and
then acidified with 1N HCl to ca. pH3. After removal of MeOH by evaporation, the mixture was successively applied to MCI
gel and silica gel column to give 5 (20 mg) as a colorless syrup; FABMS m/z: 293 [M−H]−; 1H NMR (300 MHz, CD3OD)
δ: 2.42 (dd, J=9.6, 13.2 Hz, Ha-2), 2.01 (dd, J=4.5, 13.2 Hz, Ha-2), 5.47 (dt, J=9.6, 4.5Hz, H-3), 2.21 (m, H-4), 4.15 (dd,
J=3.3, 11.7 Hz, Ha-5), 3.77 (dd, J=3.6, 11.7 Hz, Ha-5), 1.10 (d, J=6.9 Hz, CH3-6), 3.23 (s, 1-OCH3); 13C NMR (300 MHz,
CD3OD) δ: 99.9 (C1), 33.4 (C2), 71.1 (C3), 34.3 (C4), 66.4 (C5), 11.0 (CH3-6), 171.7 (COOCH3), 51.2 (1-OCH3), 167.0
(C10), 131.4 (C20), 130.5 (C30,70), 129.6 (C40,60), 134.3 (C50). (b) Compound 5 (20 mg) was treated with 10% KOH (0.5
ml) for 6 h and then neutralized with Amberlite IR-120B (H+ form) resin. After concentration, the residue was treated with
CH2N2/Et2O and subjected to a silica gel column to afforded 6 (3.3 mg). 1H NMR (300 MHz, CD3OD) δ: 1.73 (dd, J=10.8,
13.2 Hz, Ha-2), 1.92 (dd, J=4.5, 13.2 Hz, Hb-2), 4.11 (dt, J=10.8, 4.5 Hz, H-3), 1.89 (m, H-4), 3.79 (dd, J=2.4, 10.8 Hz,
Ha-5), 3.63 (dd, J=3.0, 10.8 Hz, Hb-5), 1.01 (d, J=7.2 Hz, CH3-6), 3.17 (s, 1-OCH3), 3.78 (s, COOCH3).
9. A solution of 6 (1.5 mg), dicyclohexylcardiimide (2 mg), 4-dimethylaminopyridine (1 mg) and (R)-(+)-MTPA (4 mg) in
CH2Cl2 (0.5 ml) was allowed to stand at rt for 12 h. The reaction mixture was purified by silica gel column to afford
1
(R)-MPTA ester 7 (1.4 mg): FABMS m/z: 389 [M−OCH3]−; H NMR (500 MHz, CDCl3) δ: 2.181 (dd, J=5.0, 13.0 Hz,
He-2), 2.010 (dd, J=11.5, 13.0 Hz, Ha-2), 5.559 (dt, J=11.5, 5.0 Hz, H-3), 2.222 (m, H-4), 3.893 (dd, J=2.5, 12.0 Hz, He-
5), 3.697 (dd, J=2.0, 12.0 Hz, Ha-5), 0.943 (d, J=7.0 Hz, 6-CH3), 3.262 (s, 1-OCH3), 3.809 (s, COOCH3), 3.535 (d, J=1.5,
MTPA–OCH3), 7.496 and 7.404 (MTPA phenyl protons, m). Axial orientation of OCH3 groups in 5, 6, 7 and 8 was confirmed
by DIF-NOE experiment of 7 as shown in Scheme 1. Using (S)-(−)-MTPA, the same procedure afforded (S)-MTPA ester
8 (1.5 mg): FABMS m/z: 389 [M−OCH3]−; 1H NMR (500 MHz, CDCl3) δ: 2.146 (dd, J=5.0, 13.0 Hz, He-2), 1.927 (dd,
J=11.5, 13.0 Hz, Ha-2), 5.562 (dt, J=11.5, 5.0 Hz, H-3), 2.225 (m, H-4), 3.907 (dd, J=2.5, 12.0 Hz, He-5), 3.725 (dd, J=2.0,
12.0 Hz, Ha-5), 1.080 (d, J=7.0 Hz, 6-CH3), 3.258 (s, 1-OCH3), 3.794 (s, COOCH3), 3.518 (d, J=1.5, MTPA–OCH3), 7.488
and 7.401 (MTPA phenyl protons, m).
10. Kusumi, T.; Ohtani, I.; Inouye, Y.; Kakisawa, H. Tetrahedron Lett. 1988, 29, 4731–4734.
11. Ohtani, I.; Kusumi, T., Kashman, Y.; Kakisawa, H. J. Am. Chem. Soc. 1991, 113, 4092–4096.
12. (a) Bohlmann, F.; Zdero, C. Phytochemistry 1978, 17, 759–761. (b) Macias, F. A.; Varela, R. M.; Torres, A.; Oliva, R. M.;
Molinillo, J. M. G. Phytochemistry 1998, 48, 631–636.