Synthesis of Glaucogenin D, a Structurally Unique. Disecopregnane Steroid with Potential Antiviral Activity

Supporting Information for Synthesis of Glaucogenin D, a Structurally Unique Disecopregnane Steroid with Potential Antiviral Activity Jinghan Gui,* Hailong Tian, and Weisheng Tian* Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Insitute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, China. E-mail: guijh@sioc.ac.cn; wstian@sioc.ac.cn

Table of Contents 1. General Experimental Procedure... S2 2. Full Synthetic Sequence to Glaucogenin D from hirundigenin-type intermediate 6... S3 3. Experimental Section... S3 4. Comparison of 1 H- and 13 CNMR Data for Natural vs Synthetic Glaucogenin D... S15 5. NMR Spectra... S16 S1

1. General Experimental Procedure: All reactions utilizing air- or moisture-sensitive reagents were carried out in flame-dried glassware under an argon atmosphere, unless otherwise stated. CH 2 Cl 2, DMF, t BuOH and THF were distilled prior to use according to the standard protocols. Other reagents were purchased and used as received without further purification unless otherwise stated. Reactions were magnetically stirred and monitored by thin layer chromatography (TLC) with 0.15-0.2 mm pre-coated silica gel (10-40 μm) plates. Compounds were visualized with UV light and/or by staining with ethanolic phosphomolybdic acid (PMA) followed by heating on a hot plate. Flash chromatography was performed with silica gel (200-300 mesh) under pressure. Yields refer to chromatographically and spectroscopically ( 1 H NMR) homogeneous compounds, unless otherwise stated. NMR spectra were recorded on Varian-300, Bruker-400 and Bruker-500 spectrometers in CDCl 3 with TMS as the internal standard, unless otherwise stated. Chemical shifts (δ) are given in ppm relative to residual chloroform (δ 7.26 for 1 H NMR and 77.2 for 13 C NMR), coupling constants (J) in Hz. Multiplicity is indicated as follows: s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet; br, broad. IR spectra were collected on Avatar 330 FT-IR spectrometer. Melting points were determined on SGW X-4 microscopic melting point apparatus and were uncorrected. Optical rotations were determined on JASCO P-1030 Polarimeter in the solvent indicated. High-resolution mass spectra were recorded on IonSpec 4.7 Tesla FTMS or Bruker Daltonics, Inc. APEXIII 7.0 TESLA FTMS. S2

3. Full Synthetic Sequence to Glaucogenin D from Hirundigenin-type Intermediate 6: 4. Experimental Section: A solution of 7 (15 mg, 0.023 mmol) and tetraphenylporphyrin (TPP) (ca. 1 mg) in dry DCM (5 ml) was irradiated with an incandescent lamp (200 W) while oxygen was being passed through the solution. The mixture was stirred at 0 o C for 1 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:3) afforded 9 (16 mg, >99%) as a white solid. [α] 26 D 10.9 (c 0.65, CHCl 3 ); mp 103.5-105.5 o C; IR (KBr, cm -1 ) 3419, 2931, 2857, 1748, 1428, 1384, 1104, 702, 508; 1 H NMR (300 MHz, CDCl 3 ): 0.73 (s, 3H), 1.04 (s, 9H), 1.61 (s, 3H), 2.06 (s, 3H), 2.89 (d, J = 6.6 Hz, 1H), 3.49 (d, J = 9.3 Hz, 1H), 3.56 (m, 1H), 3.77 (d, J = 9.3 Hz, 1H), 4.65 (d, J = 6.9 Hz, 1H), 5.89 (m, 1H), 6.33 (s, 3H), S3

7.36-7.42 (m, 6H), 7.61 (s, 1H), 7.66 (br d, J = 6.9 Hz, 4H); 13 C NMR (100 MHz, CDCl 3 ) δ 169.7, 136.0, 135.0, 134.9, 131.2, 129.7, 127.7, 124.7, 120.0, 113.3, 99.1, 87.4, 72.6, 72.4, 60.4, 59.0, 45.8, 40.0, 38.1, 37.2, 34.6, 31.7, 29.2, 27.3, 25.9, 25.6, 21.5, 21.4, 19.4, 13.2; HRMS (ESI) m/z (M+Na) + calcd for C 39 H 50 O 8 SiNa + 697.3173, obsd 697.3166. A solution of 7 (128 mg, 0.2 mmol) and tetraphenylporphyrin (TPP) (ca. 1 mg) in dry DCM (20 ml) was irradiated with an incandescent lamp (200 W) while oxygen was being passed through the solution. After the mixture was stirred at 0 o C for 1 h, the solvent was removed in vacuo. To another solution of FeSO 4 7H 2 O (115 mg, 0.4 mmol) and I 2 (106 mg, 0.4 mmol) in 2 ml MeOH was added under argon a solution of above mixtures in MeOH (6 ml). After stirred at RT for 1 h, the reaction mixture was quenched with saturated Na 2 S 2 O 3 solution (15 ml) and extracted with DCM (3 20 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. To the crude residue was added DCM (2 ml), DBU (0.3 ml, 2 mmol) and the mixture was stirred at 60 o C for 2 h. After the reaction mixture was cooled to RT, 5% HCl (10 ml) was added and the water phase was extracted with DCM (3 20 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:10) to afford 11 (109 mg, 83% over 3 steps) as a white solid. [α] 25 D 31.8 (c 1.60, CHCl 3 ); mp 86.3-89.2 o C; IR (KBr, cm -1 ) 2931, 2857, 1764, 1729, 1427, 1110, 702, 508; 1 H NMR (400 MHz, CDCl 3 ): 0.73 (s, 3H), 1.08 (s, 9H), 1.66 (s, 3H), 2.15(s, 3H), 2.58 (m, 1H), 3.58 (d, J = 8.0 Hz, 1H), 3.60 (m, 1H), 5.48 (dd, J = 8.0, 4.4 Hz, 1H), 6.00 (m, 1H), 6.19 (s, 1H), 6.32 (d, J = 4.4 Hz, 1H), 7.38-7.47 (m, 6H), 7.70 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 170.8, 169.6, 142.1, 135.8, 134.7, 134.0, 130.1, 129.5, 127.5, 117.3, 115.2, 97.9, 79.8, 72.0, 54. 8, 51.3, S4

39.3, 37. 9, 36.1, 34.8, 31.8, 29.6, 27.5, 27.0, 25.0, 22.9, 21.1, 19.1, 11.4; HRMS (ESI) m/z (M+Na) + calcd for C 39 H 48 O 7 SiNa + 679.3067, obsd 679.3073. A solution of 7 (99 mg, 0.15 mmol) and tetraphenylporphyrin (TPP) (ca. 1 mg) in dry DCM (10 ml) was irradiated with an incandescent lamp (200 W) and oxygen was passed through the solution. After the mixture was stirred at 0 o C for 1 h, the solvent was removed in vacuo. To another solution of FeSO 4 7H 2 O (83 mg, 0.3 mmol) and TEMPO (47 mg, 0.3 mmol) in 1 ml MeOH was added under argon a solution of above mixture in MeOH (3 ml). After stirred at RT for 1 h, the reaction mixture was quenched with 5% HCl solution (10 ml) and extracted with DCM (3 20 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:10) to afford 13 (87 mg, 71% over 2 steps) as a white solid. [α] 23 D 10.3 (c 1.65, CHCl 3 ); mp 105.2-107.3 o C; IR (KBr, cm -1 ) 2932, 2856, 1759, 1728, 1375, 1108, 702, 507; 1 H NMR (400 MHz, CDCl 3 ): 0.70 (s, 3H), 0.94 (s, 3H), 0.98 (s, 3H), 1.05 (s, 9H), 1.09 (s, 6H), 1.68 (s, 3H), 2.09 (s, 3H), 2.98 (d, J = 8.8 Hz, 1H), 3.16 (m, 1H), 3.57 (m, 1H), 4.08 (d, J = 6.0 Hz, 1H), 4.12 (d, J = 6.0 Hz, 1H), 5.67 (d, J = 7.2 Hz, 1H), 6.22 (m, 1H), 6.26 (s, 1H), 7.35-7.42 (m, 6H), 7.67 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 170.4, 169.2, 135.7, 134.7, 134.6, 134.5, 133.3, 129.5, 127.5, 119.5, 100.9, 92.9, 77.7, 75.5, 72.0, 60.3, 59.5, 59.3, 49.7, 40.6, 40.5, 39.4, 37.8, 36.0, 34.8, 34.2, 33.8, 31.8, 29.9, 27.0, 26.7, 26.2, 21.1, 20.9, 20.8, 19.1, 16.9, 11.4; HRMS (ESI) m/z (M+Na) + calcd for C 48 H 67 NO 8 SiNa + 836.4534, obsd 836.4551. S5

To a solution of 12 (15 mg, 0.02 mmol) and dibenzo-18-crown-6 (18 mg, 0.05 mmol) in dry DCM (1 ml) was added KMnO 4 (6.3 mg, 0.04 mmol) at 0 o C. After stirred at this temperature for 2 h, the reaction mixture was warmed to RT and stirring was continued for another 3.5 h. Then the reaction mixture was quenched successively with saturated NaHSO 3 solution, 5% HCl solution and extracted with DCM (3 10 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:10 1:2) to afford 15 (11 mg, 70%, 75% brsm) as a white solid, together with unreacted starting material (1 mg, 7%). [α] 26 D 37.5 (c 0.85, CHCl 3 ); mp 128.2-130.1 o C; IR (KBr, cm -1 ) 3493, 2932, 2857, 1732, 1214, 1109, 702, 506; 1 H NMR (400 MHz, CDCl 3 ): 0.79 (s, 3H), 0.97 (s, 1H), 0.98 (s, 1H), 1.05 (s, 9H), 1.09 (s, 3H), 1.10 (s, 3H), 1.65 (s, 3H), 2.83 (m, 1H), 2.93 (d, J = 9.6 Hz, 1H), 3.59 (m, 1H), 3.85 (s, 1H), 3.93 (t, J = 8.8 Hz, 1H), 4.10 (m, 2H), 4.19 (dd, J = 9.6, 8.0 Hz, 1H), 4.24 (d, J = 10.0 Hz, 1H), 5.65 (q, J = 8.8 Hz, 1H), 7.35-7.42 (m, 6H), 7.66 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 175.9, 135.7, 134.8, 134.6, 129.5, 127.5, 116.9, 93.2, 80.0, 77.2, 73.9, 71.9, 69.2, 67.9, 59.7, 59.4, 58.5, 57.9, 40.8, 40.7, 39.4, 38.1, 36.6, 35.1, 34.9, 34.3, 34.1, 31.1, 27.0, 24.5, 24.2, 21.7, 21.3, 21.1, 19.1, 16.9, 14.4; HRMS (ESI) m/z (M+H) + calcd for C 46 H 68 NO 8 Si + 790.4714, obsd 790.4715. To a solution of 15 (18 mg, 0.023 mmol) in dry DMF (1 ml) was added PDC (87 mg, 0.23 mmol) at RT. After stirred at RT for 28 h, the reaction mixture was quenched with water and extracted with DCM (3 10 ml). The combined organic layers were washed with water (3 10 ml), brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:5) to afford 16 (15 mg, 83%) as a white solid. [α] 22 D 36.7 (c 1.75, CHCl 3 ); mp 106.7-109.2 o C; IR (KBr, cm -1 ) 3479, 2932, 2856, 1732, 1249, 1111, 702, 501; 1 H NMR (400 MHz, CDCl 3 ): 0.71 (s, 3H), 0.96 (s, 1H), 0.98 (s, 1H), 1.06 (s, 9H), 1.08 (s, 3H), 1.10 (s, S6

3H), 1.64 (s, 3H), 2.26 (m, 1H), 2.64 (dd, J = 18.4, 7.2 Hz, 1H), 2.81 (m, 1H), 2.92 (d, J = 10.0 Hz, 1H), 3.63 (m, 1H), 3.92 (t, J = 9.2 Hz, 1H), 4.05 (d, J = 10.0 Hz, 1H), 4.08 (s, 1H), 4.23(m, 2H), 5.74 (q, J = 8.8 Hz, 1H), 7.37-7.43 (m, 6H), 7.66 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 204.6, 172.7, 135.7, 134.6, 134.4, 129.6, 127.6, 116.9, 93.2, 80.2, 77.2, 74.1, 71.6, 69.1, 60.9, 59.8, 59.5, 57.5, 40.8, 40.7, 40.1, 37.8, 36.3, 35.3, 34.4, 34.1, 31.3, 27.0, 24.5, 23.8, 21.4, 21.2, 21.0, 19.1, 16.9, 13.3; HRMS (ESI) m/z (M+Na) + calcd for C 46 H 65 NO 8 SiH + 788.4558, obsd 788.4575. To a solution of i Pr 2 NH (0.26 ml, 1.83 mmol) in 1 ml anhydrous THF was added at 0 o C a solution of 2.5 M n-buli (in hexane) (0.78 ml, 1.83 mmol). After stirred at this temperature for 30 min, the mixture was cooled to -78 o C and a solution of 16 (70 mg, 0.089 mmol) in 1.5 ml THF and 0.2 ml HMPA was added. After 1 h, TMSCl (0.23 ml,1.80 mmol)was added and stirring was continued for 30 min. Then the mixture was warmed to 0 o C and stirred for another 1 h before being quenched with saturated NaHCO 3 solution and extracted with EtOAc (3 20 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue of silyl enol ether 17 was used in the next step without further purification. 1 H NMR (400 MHz, CDCl 3 ): 0.05 (s, 9H), 0.14 (s, 9H), 0.70 (s, 3H), 1.01 (s, 3H), 1.07 (s, 9H), 1.09 (s, 3H), 1.63 (s, 3H), 2.46-2.55 (m, 1H), 3.08 (d, J = 10.0 Hz, 1H), 3.59-3.67 (m, 1H), 3.89 (t, J = 9.6 Hz, 1H), 4.06 (d, J = 10.0 Hz, 1H), 4.12 (t, J = 8.0 Hz, 1H), 4.22 (d, J = 10.0 Hz, 1H), 4.51 (d, J = 2.8 Hz, 1H), 5.36 (dt, J = 8.0, 10.0 Hz, 1H), 7.35-7.43 (m, 6H), 7.68 (m, 4H); HRMS (ESI) m/z (M+H) + calcd for C 52 H 82 NO 8 Si + 3 932.5348, obsd 932.5348. S7

Condition A: To the crude mixture of 17 (prepared from 16 (70 mg, 0.089 mmol) as described above) in 2 ml anhydrous THF was added NBS (95 mg, 0.533 mmol) at RT. After stirred at this temperature for 3 h, the reaction mixture was quenched with saturated NaHCO 3 solution, and extracted with DCM (3 30 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:15 1:10) to afford 18 (90 mg, >99%) as a white solid. Condition B: To the crude mixture of 17 (prepared from 16 (7 mg, 0.0089 mmol) as described above) in 1 ml anhydrous THF was added PhSeBr (21 mg, 0.089 mmol) at RT. After stirred at this temperature for 11 h, the reaction mixture was quenched with saturated NaHCO 3 solution, and extracted with DCM (3 10 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:15 1:10) to afford 18 (10 mg, >99%) as a white solid. Compound 18: [α] 28 D 23.7 (c 1.40, CHCl 3 ); mp 166.2-167.9 o C; IR (KBr, cm -1 ) 2930, 2856, 1744, 1730, 1471, 1252, 1111, 702, 503; 1 H NMR (300 MHz, CDCl 3 ): 0.15 (s, 9H), 0.68 (s, 3H), 1.00 (s, 6H), 1.08 (s, 9H), 1.09 (s, 3H), 1.10 (s, 3H), 1.64 (s, 3H), 2.19 (m, 1H), 2.39-2.46 (m, 1H), 2.76-2.85 (m, 1H), 2.92 (d, J = 10.0 Hz, 1H), 3.54-3.61(m, 1H), 3.72 (d, J = 11.6 Hz, 1H), 3.86 (t, J = 9.2 Hz, 1H), 4.01 (d, J = 10.4 Hz, 1H), 4.18-4.24 (m, 2H), 5.68 (q, J = 9.2 Hz, 1H), 7.35-7.44 (m, 6H), 7.68 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 199.26, 170.51, 135.92, 134.69, 134.43, 129.91, 129.80, 127.84, 127.74, 117.05, 83.94, 73.48, 71.78, 69.28, 62.56, 60.20, 59.88, 57.46, 47.73, 44.07, 41.02, 40.91, 39.10, 36.75, 35.48, 34.98, 34.28, 31.37, 29.87, 27.17, 24.74, 22.13, 21.36, 21.23, 19.27, 17.05, 13.99, 2.73; HRMS (ESI) m/z (M+Na) + calcd for C 49 H 72 BrNO 8 Si 2 Na + 960.3878, obsd 7 960.3874. S8

To the crude mixture of 17 (prepared from 16 (157 mg, 0.2 mmol) as described above) in 5 ml anhydrous DCM was added PhSeCl (384 mg, 2 mmol) at RT. After stirred at this temperature for 2.5 h, the reaction mixture was quenched with saturated NaHCO 3 solution, and extracted with DCM (3 30 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:8) to afford 20 (201 mg, 99%) as a white solid. [α] 27 D 26.4 (c 2.50, CHCl 3 ); mp 117.5-119.2 o C; IR (KBr, cm -1 ) 2932, 2857, 1747,1723, 1250, 1111, 847, 702, 509; 1 H NMR (400 MHz, CDCl 3 ): 0.21 (s, 9H), 0.64 (s, 3H), 0.98 (s, 3H), 0.99 (s, 3H), 1.07 (s, 9H), 1.09 (s, 3H), 1.10 (s, 3H), 1.64 (s, 3H), 2.17-2.24 (m, 1H), 2.48 (m, 1H), 2.85-2.89 (m, 3H), 3.55-3.63 (m, 1H), 3.87 (t, J = 9.2 Hz, 1H), 4.03 (d, J = 10.0 Hz, 1H), 4.18-4.24 (m, 2H), 5.73 (q, J = 9.2 Hz, 1H), 7.24-7.28 (m, 3H), 7.36-7.44 (m, 6H), 7.55-7.57 (m, 2H), 7.68-7.71 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 204.39, 170.78, 135.94, 135.92, 134.74, 134.71, 132.29, 129.81, 129.77, 129.33, 128.17, 127.80, 127.75, 117.01, 93.45, 84.04, 77.29, 73.21, 72.28, 69.29, 62.77, 59.97, 59.62, 57.47, 51.25, 43.61, 41.11, 40.97, 38.95, 36.64, 35.55, 35.07, 34.40, 31.45, 29.87, 27.18, 24.76, 23.60, 22.16, 21.43, 21.25, 19.29, 17.09, 13.54, 3.20; LR-MS (ESI) m/z (M+Na) + : 1038.3 (Acquisition of HRMS data (ESI or MALDI) was met with failure possiblely due to the high MW of the molecule). To a solution of 20 (61 mg, 0.06 mmol) in 3 ml CH 3 CN was added an aqueous 40% HF solution (0.03 ml, 0.6 mmol) and the resulting solution was stirred at RT for 1 day. S9

Then the reaction mixture was quenched with saturated NaHCO 3 solution (15 ml) and extracted with EtOAc (3 20 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue of 21 was dissolved in DCM (10 ml) and O 3 was passed through the solution while cooling at 78 o C. After 1 min, a blue color appeared and the ozone bubbler was replaced with an argon bubbler to give a colorless solution. Then 0.01 ml i Pr 2 NH was added and the solution was warmed to RT. To the crude mixture, obtained by evaporation of the solvent under reduced pressure, in 2 ml toluene was added 0.01 ml i Pr 2 NH and the resulting solution was stirred at 60 o C for 1 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:1 2:1) afforded 22 (17 mg, 52%) as a white solid. Compound 21: [α] 27 D 61.7 (c 1.00, CHCl 3 ); mp 192.3-194.6 o C; IR (KBr, cm -1 ) 3536, 3311, 2934, 2870, 1745, 1706, 1270, 738; 1 H NMR (400 MHz, CDCl 3 ): 0.72 (s, 3H), 1.01 (s, 3H), 1.02 (s, 3H), 1.10 (s, 3H), 1.12 (s,3h), 1.65 (s, 3H), 2.40 (m, 1H), 2.63 (m, 1H), 2.92 (m, 2H), 3.00 (d, J = 11.2 Hz, 1H), 3.69 (m, 1H), 3.94 (t, J = 9.2 Hz, 1H), 4.07 (m, 2H), 4.24 (m, 2H), 5.82 (q, J = 8.4 Hz, 1H), 7.28 (m, 3H), 7.65 (m, 2H); 13 C NMR (101 MHz, CDCl 3 ) δ 204.78, 172.26, 134.57, 131.57, 129.45, 128.41, 117.09, 93.46, 81.11, 74.15, 70.30, 69.46, 61.26, 60.12, 59.82, 57.83, 50.70, 44.15, 40.98, 40.88, 38.31, 36.40, 35.54, 34.52, 34.25, 31.18, 24.59, 24.29, 21.67, 21.39, 21.22, 17.07, 13.38; HRMS (ESI) m/z (M+Na) + calcd for C 36 H 51 NO 8 SeNa + 722.2737, obsd 722.2721. Compound 22: [α] 26 D 71.4 (c 0.85, CHCl 3 ); mp 122.5-124.6 o C; IR (KBr, cm -1 ) 3467, 2933, 1739, 1674, 1466, 1239, 1061, 877; 1 H NMR (400 MHz, CDCl 3 ): 0.99 (s, 3H), 1.00 (s, 3H), 1.11 (s, 6H), 1.31 (s, 3H), 1.61 (s, 3H), 2.55 (m, 2H), 2.64 (m, 1H), 2.85 (d, J = 9.2 Hz, 1H), 3.35 (m, 1H), 3.73 (m, 1H), 3.95 (s, 1H), 4.00 (m, 2H), 4.15 (m, 2H), 5.89 (s, 1H), 5.90 (m, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 192.09, 173.80, 167.49, 122.05, 116.79, 79.73, 74.77, 73.18, 70.48, 60.24, 59.82, 59.59, 53.44, 43.14, 40.97, 40.83, 40.22, 38.25, 34.27, 34.13, 31.81, 27.00, 24.23, 24.10, 21.53, 21.19, 20.75, 17.09; HRMS (ESI) m/z (M+Na) + calcd for C 30 H 45 NO 8 Na + 570.3043, obsd 570.3018. S10

Preparation of then SmI 2 solution in THF: To a suspension of powdered Sm (105 mg, 0.696 mmol) in 2 ml THF was added CH 2 I 2 (27 μl, 0.348 mmol). The mixture was stirred at room temperature for 1 h, observing the appearance of a dark blue color. To a solution of 22 (16 mg,0.029 mmol) in THF (1 ml) and t-buoh (0.1 ml) was added at -78 o C a solution of SmI 2 in THF (1 ml, ca. 0.087 mmol) freshly prepared as described above. The reaction mixture was stirred at this temperature for 10 min and opened to air untill a yellow color appeared. Then a saturated NaHCO 3 solution (15 ml) was added, and the mixture was warmed to RT and extracted with DCM (3 15 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. To this crude mixture in 2 ml MeOH at 0 o C was added sequentially CeCl 3 7H 2 O (32 mg, 0.087 mmol), NaBH 4 (4 mg, 0.087 mmol). After stirred at 0 o C for 1 h, the reaction mixture was quenched with saturated NH 4 Cl solution (15 ml) and extracted with DCM (3 15 ml). The combined organic layers were washed with brine, dried over Na 2 SO 4, and concentrated in vacuo. The crude residue was purified by flash chromatography (EtOAc: PE=1:1 2:1) to afford 23 (9 mg, 58% for 2 steps) as a white solid. [α] 27 D -3.5 (c 0.65, CHCl 3 ); mp 100.7-103.2 o C; IR (KBr, cm -1 ) 3432, 2930, 2854, 1736, 1464, 1163, 1048, 828; 1 H NMR (400 MHz, CDCl 3 ): 1.01 (s, 3H), 1.13 (s, 3H), 1.14 (s, 3H), 1.26 (s, 6H), 1.65 (s, 3H), 2.20-2.26 (m, 1H), 2.36-2.43 (m, 2H), 2.82 (d, J = 9.2 Hz, 1H), 3.24-3.33 (m, 1H), 3.53-3.61 (m, 1H), 3.99 (dd, J = 10.0, 5.6 Hz, 1H), 4.11 (dd, J = 9.6, 6.8 Hz, 1H), 4.17 (d, J = 9.6 Hz, 1H), 4.24 (d, J = 9.6 Hz, 1H), 4.64 (br d, J = 9.6 Hz, 1H), 5.41 (s, 1H), 5.86 (dt, J = 9.6, 6.4 Hz, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 174.29, 142.95, 124.59, 116.95, 93.20, 77.11, 72.36, 71.57, 70.48, 68.20, 60.07, 59.69, 59.36, 49.21, 48.30, 41.67, 40.96, 40.87, 38.83, 36.23, S11

34.24, 34.21, 31.37, 24.88, 24.29, 22.72, 21.63, 21.31, 18.03, 17.13; HRMS (ESI) m/z (M+H) + calcd for C 30 H 48 NO 7 + 534.3431, obsd 534.3410. To a solution of 23 (10 mg, 0.0188 mmol) in 2 ml toluene was added 0.01 ml i Pr 2 NH and the resulting solution was stirred at 120 o C for 1 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:1 EA) afforded 24 (6 mg, 85%) as a white solid. [α] 28 D 2.6 (c 0.30, CHCl 3 ); mp 241.9-243.5 o C; IR (KBr, cm -1 ) 3416, 2930, 2854, 1725, 1151, 1047, 809; 1 H NMR (400 MHz, CDCl 3 ): 1.09 (s, 3H), 1.55 (s, 3H), 3.22 (d, J = 8.0 Hz, 1H), 3.55-3.62 (m, 1H), 4.10 (dd, J = 6.4, 4.0 Hz, 1H), 4.22 (dd, J = 10.4, 6.4 Hz, 1H), 4.39 (d, J = 12.8 Hz, 1H), 4.48-4.52 (m, 2H), 5.05 (dd, J = 12.4, 1.2 Hz, 1H), 5.39 (s, 1H), 5.61-5.65 (m, 1H); 13 C NMR (101 MHz, CDCl 3 ) δ 178.36, 142.78, 142.72, 124.85, 124.52, 115.81, 78.31, 71.49, 71.21, 71.11, 70.25, 56.60, 50.67, 50.60, 41.73, 38.18, 37.10, 31.63, 29.36, 23.21, 19.94; HRMS (ESI) m/z (M+Na) + calcd for C 21 H 28 O 6 Na + 399.1784, obsd 399.1777. To a solution of 24 (3 mg, 0.0056 mmol) in 1 ml n PrOH was added RhCl(PPh 3 ) 3 1 mg and the resulting solution was stirred at 120 o C for 2 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=2:1) afforded glaucogenin D, 4 (2 mg, 66%) as a white solid. [α] 29 D 73.6 (c 0.09, CHCl 3 ); m.p. 78.1-80.0 1 ; IR (KBr, cm -1 ) 3425, 2929, 2855, 1737, 1383, 1083, 807, 609; 1 H NMR (400 MHz, CDCl 3 ): 0.99 (s, 3H), 1.54 (s, 3H), 2.54-2.62 (m, 1H), 3.45 (d, J = 1 Since we can not obtain a crystal form of glaucogenin D, the m.p. data herein is much smaller than the reported data (m.p. 173-176 o C, white needle crystal from acetone-h 2 O). See: Dou, J.; Bi, Z.-M.; Zhang, Y.-Q.; Li, P. Chin. J. Nat. Med. 2006, 4, 192. S12

7.6 Hz, 1H), 3.52-3.59 (m, 1H), 3.85 (t, J = 9.2 Hz, 1H), 4.17 (t, J = 8.8 Hz, 1H), 4.62 (br d, J = 10.0 Hz, 1H), 5.34-5.39 (m, 1 H), 5.39 (s, 1H), 6.26 (s, 1H); 1 H NMR (400 MHz, Py): 0.91 (s, 3H), 1.51 (s, 3H), 3.59 (d, J = 8.0 Hz, 1H), 3.84 (m, 1H), 3.91 (dd, J = 9.6, 8.8 Hz, 1H), 4.11 (dd, J = 8.4, 7.2 Hz, 1H), 5.07 (d, J = 9.6 Hz, 1H), 5.43 (dt, J = 9.2, 7.6 Hz, 1H), 5.75 (s, 1H), 6.46 (s, 1H); 13 C NMR (101 MHz, Py) δ 175.00, 144.03, 142.40, 126.70, 118.67, 114.54, 75.84, 71.09, 67.97, 67.87, 56.39, 51.40, 50.81, 42.81, 38.79, 36.58, 32.40, 30.22, 24.80, 23.73, 17.92; HRMS (ESI) m/z (M-H) - calcd for C 21 H 27 O - 6 375.1813, obsd 375.1826. To a solution of 12 (8 mg, 0.01 mmol) in 1 ml toluene was added 0.01 ml i Pr 2 NH and the resulting solution was stirred at 120 o C for 2 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:15 1:5) afforded 25 (6 mg, 95%) as a white solid. [α] 24 D 2.7 (c 0.85, CHCl 3 ); mp 72.1-74.5 o C; IR (KBr, cm -1 ) 2930, 2856, 1715, 1427, 1230, 1109, 702, 508; 1 H NMR (400 MHz, CDCl 3 ): 0.84 (s, 3H), 1.05 (s, 9H), 1.51 (s, 3H), 2.33 (m, 1H), 2.51 (m, 1H), 3.16 (d, J = 7.6 Hz, 1H), 3.54-3.62 (m, 1H), 4.10 (dd, J = 10.8, 4.0 Hz, 1H), 4.19 (dd, J = 10.8, 6.0 Hz, 1H), 4.31 (d, J = 12.4 Hz, 1H), 4.42 (d, J = 12.4 Hz, 1H), 5.18 (m, 1H), 5.59 (m, 1H), 5.89 (m, 1H), 7.34-7.42 (m, 6H), 7.66 (m, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 173.4, 142.0, 136.4, 135.7, 134.7, 134.6, 129.5, 127.9, 127.5, 126.6, 115.6, 79.9, 72.0, 70.8, 70.3, 56.9, 51.3, 40.3, 37.7, 37.2, 34. 8, 31.3, 28.8, 28.7, 27.0, 23.0, 19.1, 14.0; HRMS (ESI) m/z (M+Na) + calcd for C 37 H 46 O 5 SiNa + 621.3012, obsd 621.3031. S13

Condition A: To a solution of 25 (14 mg, 0.023 mmol) in 1 ml anhydrous toluene was added 0.01 ml DIPEA and RuCl 2 (PPh 3 ) 2 (19 mg, 0.02 mmol) and the resulting solution was stirred at 120 o C for 24 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:10) afforded 10 (10 mg, 71%, >99% brsm) as a white solid, together with unreacted starting material (4 mg, 39%). Condition B: To a solution of 25 (5 mg, 0.0084 mmol) in 1 ml n PrOH was added RhCl(PPh 3 ) 3 (1 mg, 0.0011 mmol) and the resulting solution was stirred at 110 o C for 1.5 h. Evaporation of the solvent under reduced pressure and flash chromatography of the residue (EtOAc: PE=1:10) afforded 10 (5mg, >99%) as a white solid. Compound 10: [α] 26 D 27.9 (c 1.75, CHCl 3 ); mp 73.8-75.4 o C; IR (KBr, cm -1 ) 2931, 2856, 1723, 1654, 1110, 865; 1 H NMR (400 MHz, CDCl 3 ): 0.68 (s, 3H), 1.05 (s, 9H), 1.26 (s, 3H), 2.06 (m, 1H), 2.56 (m, 1H), 3.42 (d, J = 7.6 Hz, 1H), 3.54-3.60 (m, 1H), 3.79 (t, J = 9.2 Hz, 1H), 4.21 (t, J = 7.6 Hz, 1H), 5.36 (dt, J = 9.2, 7.6 Hz, 1H), 6.00 (br s, 1H), 6.25(s, 1H), 7.35-7.42 (m, 6H), 7.67 (br d, J = 7.2 Hz, 4H); 13 C NMR (101 MHz, CDCl 3 ) δ 170.7, 143.2, 135.7, 134.7, 134.6, 130.1, 129.5, 127.5, 117.1, 113.8, 75.1, 72.0, 67.7, 55.4, 51.8, 39.3, 37.9, 36.1, 34.8, 31.8, 29.6, 28.4, 27.0, 24.6, 23.8, 19.1, 11.4; HRMS (MALDI) m/z (M+Na) + calcd for C 37 H 46 O 5 SiNa + 621.3012, obsd 621.3007. S14

5. Comparison of 1 H- and 13 CNMR Data for Natural vs Synthetic Glaucogenin D. Comparison of 1 H NMR chemical shifts (Py-d5) Proton Natural Glaucogenin D 2 Synthetic Glaucogenin D (400 MHz) Δδ 18-CH 6.46 (s) 6.46 (s) 0 6-CH 5.75 (d, J = 1.5 Hz) 5.75 (s) 0 16-CH 5.43 (dd, J = 9.0, 7.8 Hz) 5.43 (dt, J = 9.2, 7.6 Hz) 0 7-CH 5.06 (d, J = 9.5 Hz) 5.07 (d, J = 9.6 Hz) 0.01 15-CH α 4.11 (dd, J = 8.5, 7.0 Hz) 4.11 (dd, J = 8.4, 7.2 Hz) 0 15-CH β 3.91 (t, J = 9.3 Hz) 3.91 (dd, J = 9.6, 8.8 Hz) 0 3-CH 3.84 (m) 3.84 (m) 0 17-CH 3.59 (d, J = 9.0 Hz) 3.59 (d, J = 8.0 Hz) 0 21-Me 1.51 (s) 1.51 (s) 0 19-Me 0.92 (s) 0.91 (s) 0.01 Comparison of 13 C NMR chemical shifts (Py-d5) Synthetic Glaucogenin D Proton Natural Glaucogenin D 2 (100 MHz) Δδ C-1 36.6 36.6 0 C-2 32.4 32.4 0 C-3 71.1 71.1 0 C-4 42.8 42.8 0 C-5 142.4 142.4 0 C-6 126.7 126.7 0 C-7 68.0 68.0 0 C-8 51.5 51.4 0.1 C-9 50.8 50.8 0 C-10 38.8 38.8 0 C-11 23.8 23.7 0.1 C-12 30.3 30.2 0.1 C-13 118.7 118.7 0 C-14 175.0 175.0 0 C-15 67.9 68.0-0.1 C-16 75.9 75.8 0.1 C-17 56.5 56.4 0.1 C-18 144.0 144.0 0 C-19 18.0 17.9 0.1 C-20 114.6 114.5 0.1 C-21 24.8 24.8 0 2 Dou, J.; Bi, Z.-M.; Zhang, Y.-Q.; Li, P. Chin. J. Nat. Med. 2006, 4, 192. S15

5. NMR Spectra: S16

1 H NMR (after exchange with D 2 O) 1 H NMR (original spectrum) S17

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1 H NMR (after exchange with D 2 O) 1 H NMR (original spectrum) S38

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1 H NMR (after exchange with D 2 O) 1 H NMR (original spectrum) S43

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DEPT 135 DEPT 90 13 C NMR S45

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DEPT 135 DEPT 90 13 C NMR S62

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DEPT 135 DEPT 90 grease 13 C NMR S65

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Glaucogenin D (100 MHz, Py-d5) S68