Enantioselective Synthesis of ( )-Jiadifenin, a Potent Neurotrophic Modulator

Enantioselective Synthesis of ( )-Jiadifenin, a Potent Neurotrophic Modulator Lynnie Trzoss, Jing Xu,* Michelle H. Lacoske, William C. Mobley and Emmanuel A. Theodorakis* Department of Chemistry and Biochemistry, University of California, San Diego 9500 Gilman Drive, La Jolla, California, 92093-0358, USA Department of Neurosciences, University of California, San Diego 9500 Gilman Drive, La Jolla, California 92093-0752, USA SUPPRTING INFRMATIN General Procedures S 1 Experimental Procedures S 2 S 9 NMR Spectra S 10 S 25

General Procedures. Unless indicated, all commercially available reagents and anhydrous solvents were purchased at the highest commercial quality and were used as received without further purification. All non-aqueous reactions were carried out under argon atmosphere using dry glassware that had been flame-dried under a stream of argon unless otherwise noted. Anhydrous tetrahydrofuran (THF) was obtained by passing commercially available pre-dried, oxygen-free formulations through activated alumina columns. Flash column chromatography was performed on silica gel (Merck Kieselgel 60, 230-400 mesh) using CH 2 Cl 2 -MeH mixtures of increasing polarity. The progress of all the reactions was monitored by thin-layer chromatography (TLC) using glass plates precoated with silica gel-60 F 254 to a thickness of 0.5 mm (Merck). 13 C NMR and 1 H NMR spectra were recorded on either 500 MHz/800 MHz Varian instrument or a 500 MHz JEL instrument. CDCl 3 was treated with flame dried K 2 C 3, chemical shifts (δ) are quoted in parts per million (ppm) referenced to the appropriate residual solvent peak or TMS internal reference (CHCl 3, CD 3 D or pyridine-d 5 -TMS), with the abbreviations s, br s, d, t, q, m, qd and dt denoting singlet, broad singlet, doublet, triplet, quartet, multiplet, quartet of doublet and doublet of triplets respectively. J = coupling constants given in Hertz (Hz). High resolution Mass spectra (HRMS) were recorded on a trisector WG AutoSpecQ spectrometer. ptical rotation data were collected on a Jasco P-1010 polarimeter using HPLC grade anhydrous CH 2 Cl 2, anhydrous MeH, anhydrous EtH or anhydrous THF. X-ray data were recorded on a Bruker SMART APEX 3kW Sealed Tube X-ray diffraction system. 1

H 1. Martin sulfurane, THF H H 2. H 2, Pd/C, MeH 4 10 Compound 10: To a solution of alcohol 4 [1] (420 mg, 1.5 mmol) in anhydrous THF (20 ml) was added Martin sulfurane (4.0 g, 9.0 mmol) in one portion at RT. This dark brown solution was allowed to stir at the same temperature for 2 hrs before rotavaped to dryness. The residue was re-dissolved in MeH (20 ml), Pd/C (10%, 530 mg, 0.5 mmol) was then loaded under argon atmosphere. This crude diene was then selectively hydrogenated using a double-layer H 2 -balloon for 30 min. The mixture was passed through a short silica pad and thoroughly rinsed (CH 2 Cl 2 :MeH, 20:1) and the filtrate was concentrated under reduced pressure. The residue was purified via silica flash column chromatography (CH 2 Cl 2 :MeH = 200:1 to 100:1) to afford compound 10 as white foams (284 mg, 72% over 2 steps). R f = 0.65 (silica gel, EtAc:Hexanes = 2:1); [α] 23 D 44.6 (c 1.21, CH 2 Cl 2 ); 1 H NMR (500 MHz, CDCl 3 ) δ 5.88, (br s, 1H), 4.69 (dd, J = 2.7 Hz, 2.7 Hz, 1H), 3.98 (d, J = 9.8 Hz, 1H), 3.85 (d, J = 9.8 Hz, 1H), 3.08 (br s, 1H), 2.77 (d, J = 18.9 Hz, 1H), 2.62 (d, J = 18.9 Hz, 1H), 2.45-2.33 (m, 2H), 1.94 (m, 1H), 1.84 (m, 1H), 1.71-1.60 (m, 2H), 1.36 (s, 3H); 13 C NMR (125 MHz, CDCl 3 ) δ 177.6, 169.1, 144.4, 130.5, 79.9, 77.0, 75.9, 43.9, 43.4, 42.4, 40.0, 31.9, 29.1, 22.3; HRMS (ESI): m/e 265.1072 [M+H] + calcd for C 14 H 17 + 5 : 265.1071. H Mn 3 (Ac) 9, tbuh EtAc, 3Å MS 40 ºC, 16 h H 10 11 Enone 11: To a solution of compound 10 (140 mg, 0.53 mmol) in anhydrous EtAc (4 ml) was added tert-butyl hydroperoxide (960 µl, ~ 10 eq., 5~6 M in decane) and 3Å molecular sieves (200 mg). The mixture was stirred for 30 min at RT. Manganese(III) acetate dehydrate (71.0 mg, 0.27 mmol) was added to this mixture in one portion, and this reaction was heated at 40 C for 16 hrs. The solution was cooled 2

down, silica gel (2 g) was added in and rotavaped to dryness. The silica-absorbed crude product was then purified via silica flash column chromatography (CH 2 Cl 2 :MeH = 100:1 to 20:1) to afford enone 11 as white solid (96 mg, 65%). R f = 0.25 (silica gel, CH 2 Cl 2 :MeH = 20:1); [α] 24 D 82.3 (c 1.42, MeH); 1 H NMR (500 MHz, CD 3 D) δ 6.29, (s, 1H), 4.78 (dd, J = 4.6 Hz, 1.7 Hz, 1H), 4.14 (d, J = 10.3 Hz, 1H), 4.03 (d, J = 10.9 Hz, 1H), 3.11 (d, J = 18.9 Hz, 1H), 2.87 (dd, J = 19.5 Hz, 2.7 Hz, 1H), 2.64 (d, J = 18.9 Hz, 1H), 2.43 (dd, J = 14.3Hz, 4.0 Hz, 1H), 2.40 (d, J = 18.9 Hz, 1H), 2.32 (dt, 14.3 Hz, 2.3 Hz, 1H), 1.45 (s, 3H); 13 C NMR (125 MHz, CD 3 D) δ 206.8, 181.1, 177.3, 170.4, 133.9, 80.2, 80.0, 74.4, 51.3, 45.5, 43.2, 42.4, 32.1, 22.4; HRMS (ESI): m/e 277.0719 [M H] - calcd for C 14 H 13-6 : 277.0718. H LDA, MeI, THF, 78 ~ 10 ºC, 2 h 11 12 13 Compound 12 and 13: To a solution of enone 11 (20 mg, 71.9 µmol) in THF (800 µl) was added freshly prepared LDA solution (360 µl, 1M in THF) at 78 C, this solution was slowly warmed up to 15 C over 1 h and stirred at 15 C for 30 min. This solution was cooled to 40 C, MeI (14 µl, 216 µmol) was dropped in slowly. This reaction was slowly warmed up to 10 C over 1 h and stirred at 10 C for 30 min before quenched with saturated NH 4 Cl solution (1 ml). This mixture was diluted with EtAc (200 ml) and dried over Na 2 S 4, filtrated and concentrated. The residue was purified via preparative TLC (CH 2 Cl 2 :MeH:THF = 80:1:1 x 8 times) to afford compound 12 and 13 as small white crystals. 12: 11 mg, 50%; R f = 0.38 (silica gel, CH 2 Cl 2 :MeH:THF = 60:1:1 x 2 times); [α] D 22 286.4 (c 0.16, THF); 1 H NMR (500 MHz, CD 3 D) δ 6.32 (s, 1H), 4.74 (dd, J = 4.6 Hz, 1.2 Hz, 1H), 4.14 (d, J = 10.3 Hz, 1H), 4.09 (d, J = 10.9 Hz, 1H), 2.83 (qd, J = 7.5 Hz, 1.7 Hz, 1H), 2.76 (d, J = 18.4 Hz, 1H), 2.63 (dd, J = 14.9 Hz, 4.6 Hz, 1H), 2.42 (d, J = 18.4 Hz, 1H), 2.16 (dt, 14.9 Hz, 1.8 Hz, 1H), 1.49 (d, J = 7.4 Hz, 3H), 1.46 (s, 3H); 13 C NMR (125 MHz, CD 3 D) δ 206.8, 182.0, 177.4, 174.9, 134.3, 79.9, 79.6, 74.5, H + H 3

47.8, 46.5, 45.8, 45.3, 27.7, 23.2, 18.6; HRMS (ESI): m/e 293.1023 [M+H + ] calcd for C 15 H 17 + 6 : 293.1020. 13: 6 mg, 25%; R f = 0.4 (silica gel, CH 2 Cl 2 :MeH:THF = 60:1:1 x 2 times); [α] 23 D 276.6 (c 0.30, THF); 1 H NMR (500 MHz, CD 3 D) δ 6.32 (s, 1H), 4.77 (dd, J = 4.6 Hz, 1.2 Hz, 1H), 4.15 (d, J = 10.3 Hz, 1H), 4.11 (d, J = 10.9 Hz, 1H), 2.77 (qd, J = 7.5 Hz, 1.8 Hz, 1H), 2.58 (q, J = 7.6 Hz, 1H), 2.51 (dd, J = 14.9 Hz, 4.3 Hz, 1H), 2.07 (dt, J = 14.3, 1.8 Hz, 1H), 1.51 (d, J = 7.5 Hz, 3H), 1.45 (s, 3H), 1.14 (d, J = 7.5 Hz, 3H); 13 C NMR (125 MHz, CD 3 D) δ 210.2, 181.3, 177.4, 175.0, 133.0, 80.1, 79.8, 74.5, 50.0, 49.4, 46.8, 45.5, 23.7, 23.3, 18.2, 12.7; HRMS (ESI): m/e 307.1177 [M+H] + calcd for C 16 H 19 + 6 : 307.1176. 11 H NaHMDS, Davis oxaziridine (1 eq.), THF, 78 ºC, 1 h Compound 14: To a solution of enone 11 (20 mg, 71.9 µmol) in THF (500 µl) was added NaHMDS (216 µl, 216 µmol, 1M in THF) dropwise at 78 C, this solution was stirred for 20 min. Then the Davis oxaziridine (18.8 mg, 71.9 µmol) in THF (200 µl) was added in dropwise. This solution was stirred at the same temperature for 30 min before quenched with saturated NH 4 Cl solution (1 ml). This mixture was diluted with EtAc (200 ml) and dried over Na 2 S 4, filtrated and concentrated. The residue was purified via silica flash column chromatography (CH 2 Cl 2 :MeH = 100:1 to 20:1) to afford compound 14 as small white crystals (13 mg, 61%). R f = 0.4 (silica gel, CH 2 Cl 2 :MeH = 20:1 x 2 times); [α] D 25 136.4 (c 0.83, THF); 1 H NMR (500 MHz, CD 3 D) δ 6.38 (s, 1H), 4.75 (dd, J = 4.6 Hz, 1.2 Hz, 1H), 4.12 (d, J = 10.9 Hz, 1H), 3.94 (d, J = 10.9 Hz, 1H), 4.09 (d, J = 1.2 Hz, 1H), 3.90 (d, J = 10.3 Hz, 1H), 3.00 (d, J = 18.9 Hz, 1H), 2.70 (dd, J = 14.4 Hz, 4.6 Hz, 1H), 2.38 (d, J = 18.9 Hz, 1H), 2.17 (dt, J = 14.3, 1.8 Hz, 1H), 1.46 (s, 3H); 13 C NMR (125 MHz, CD 3 D) δ 207.4, 178.8, 177.4, 171.2, 135.6, 80.2, 79.4, 74.5, 73.2, 49.5, 47.1, 45.3, 26.8, 22.9; HRMS (ESI): m/e 293.0668 [M H] - calcd for C 14 H 13 7 - : 293.0667. H 14 H 4

H H LDA, MeI THF, HMPA, 78 ~ 10 ºC, 4 h H H Jones reagent acetone, rt, 20 min, then MeH, rt, 15 min H C 2 Me H 14 3 1: ( )-jiadifenin ( )-Jiadifenin (1): To freshly prepared LDA solution (476 µl, 1M in THF) was added a solution of 14 (28 mg, 95.2 µmol) in THF (1 ml) at 78 C, this solution was slowly warmed up to 20 C over 1 h and stirred at 20 C for 30 min. This solution was cooled to 40 C, HMPA (19.9 µl, 114 µmol) and MeI (7.1 µl, 114 µmol) was dropped in slowly. This reaction was slowly warmed up to 10 C over 1 h and stirred at 10 C for 4 h before quenched with saturated NH 4 Cl solution (1 ml). This mixture was diluted with EtAc (200 ml) and dried over Na 2 S 4, filtrated and concentrated. The residue was purified via preparative TLC (CH 2 Cl 2 :MeH = 20:1 x 5 times) to afford methylated enone 3 (~ 11 mg, 60% brsm, contaminated with trace of 14) and recovered compound 14 (10 mg). Without intensive purification of 3, to a solution of this methylated enone 3 (11.0 mg, 35.7 µmol) in acetone (3 ml) was added Jones reagent (2.6 M, 200 µl, 2.67 M) at RT and the resulting mixture was stirred for 20 min. The reaction mixture was quenched with MeH at RT (1 ml) and stirred for 15 min. The reaction mixture was cooled to 0 C, quenched with saturated NaHC 3 (1 ml), diluted with EtAc (100 ml) and dried over Na 2 S 4, filtrated and concentrated. The residue was purified via preparative TLC (CH 2 Cl 2 :MeH = 50:1 x 3 times, then CH 2 Cl 2 :MeH = 35:1 x 3 times) to afford ( )-Jiadifenin (1) as white foams (5.4 mg, 45%). R f = 0.3 (silica gel, CH 2 Cl 2 :MeH = 20:1 x 2 times); [α] 24 D 123.8 (c 0.17, EtH); 1 H NMR (500 MHz, pyridine-d 5 -TMS) δ 10.94 (major C-10 anomer, br s, 1H), 10.64* (minor C-10 anomer, br s, 1H), 9.14* (br s, 1H), 9.08 (br s, 1H), 6.59 (s, 1H), 6.52* (s, 1H), 5.89 (d, J = 8.6 Hz, 1H), 5.14* (d, J = 6.3 Hz, 1H), 5.07 (d, J = 6.3 Hz, 1H), 4.44* (d, J = 9.2 Hz, 1H), 4.22 (d, J = 8.6 Hz, 1H), 4.18* (d, J = 9.2 Hz, 1H), 3.69 (s, 3H), 3.57* (s, 3H), 3.53* (q, J = 7.5 Hz, 1H), 3.19* (dd, J = 12.0, 6.3 Hz, 1 H), 3.04 (dd, J = 12.6, 6.3 Hz, 1 H), 2.97 (q, J = 7.6 Hz, 1 H), 2.64* (d, J = 12.1 Hz, 1 H), 2.54 (d, J = 12.6 Hz, 1 H), 1.70 (s, 3 H), 1.65* (s, 3 H), 1.39* (d, J = 7.4 Hz, 3 H), 1.25 (d, J = 8.0 Hz, 3 H); 13 C NMR (200 MHz, pyridine-d 5 -TMS) δ 209.7* (minor 5

C-10 anomer), 208.9 (major C-10 anomer), 180.2, 179.0, 178.7*, 177.4*, 171.6, 169.2*, 131.3*, 130.7, 106.0, 104.1*, 81.0, 80.6, 80.4*, 79.5*, 76.1, 75.4*, 61.5*, 60.3, 52.7, 52.0*, 45.2, 44.9*, 44.8*, 43.0, 31.6*, 31.4, 23.3, 23.2*, 14.5*, 13.1; HRMS (ESI): m/e 339.1072 [M+H] + calcd for C 16 H 19 + 8 : 339.1074. H 11 C 2Me 15 10 1 8 9 7 2 3 4 5 6 1: jiadifenin H 13 14 12 Table 1. 1 H NMR datum comparison of the synthetic 1 with natural ( )-jiadifenin and synthetic (±)-1 (data reported in ref. 2 and ref. 3, respectively) Position δ (natural) δ (synthetic 1, ±) δ (synthetic 1, ) (C 5 D 5 N, 600MHz) 2 (C 5 D 5 N, 500MHz) 3 (C 5 D 5 N, 500MHz) Δ 1 Δ 2 1 2.93, q, 7.7 Hz 2.95, q, 7.6 Hz 2.97, q, 7.6 Hz + 0.04 + 0.02 1* 3.49, q, 7.7 Hz 3.51, q, 7.7 Hz 3.52, q, 7.5 Hz + 0.03 + 0.01 3 6.56, s 6.57, s 6.59, s + 0.03 +0.02 3* 6.48, s 6.50, s 6.52, s + 0.04 +0.02 7 5.03, d, 6.3 Hz 5.05, d, 6.2 Hz 5.07, d, 6.3 Hz + 0.04 + 0.02 7* 5.11, d, 6.3 Hz 5.12, d, 6.2 Hz 5.14, d, 6.3 Hz + 0.03 + 0.02 8 2.55, d, 12.3 Hz 2.53, d, 12.4 Hz 2.54, d, 12.6 Hz 0.01 + 0.01 3.00, dd, 12.3 Hz, 3.03, dd, 12.4 Hz, 3.04, dd, 12.6 Hz, + 0.04 + 0.01 6.3 Hz 6.2 Hz 6.3 Hz 8* 2.60, d, 11.8 Hz 2.62, d, 11.8 Hz 2.64, d, 12.1 Hz + 0.04 + 0.02 3.15, dd, 11.8 Hz, 3.17, dd, 11.8 Hz, 3.19, dd, 12.0 Hz, + 0.04 + 0.02 6.3 Hz 6.3 Hz 6.3 Hz 13 1.67, s 1.69, s 1.70, s + 0.03 + 0.01 13* 1.62, s 1.64, s 1.65, s + 0.03 + 0.01 14 4.19, d, 8.5 Hz 4.20, d, 8.4 Hz 4.22, d, 8.6 Hz + 0.03 + 0.02 5.85, d, 8.5 Hz 5.87, d, 8.5 Hz 5.89, d, 8.6 Hz + 0.04 + 0.02 14* 4.15, d, 9.1 Hz 4.16, d, 9.0 Hz 4.18, d, 9.2 Hz + 0.03 + 0.02 4.41, d, 9.1 Hz 4.43, d, 9.0 Hz 4.44, d, 9.2 Hz + 0.03 + 0.01 15 1.22, d, 7.7 Hz 1.24, d, 7.7 Hz 1.25, d, 8.0 Hz + 0.03 + 0.01 15* 1.32, d, 7.7 Hz 1.38, d, 7.7 Hz 1.39, d, 7.4 Hz + 0.07 + 0.01 CH 3 3.66, s 3.68, s 3.69, s + 0.03 + 0.02 CH 3 * 3.54, s 3.56, s 3.57, s + 0.03 + 0.01 6

Table 2. 13 C NMR datum comparison of the synthetic 1 with natural ( )-jiadifenin and synthetic (±)-jiadifenin (data reported in ref. 2 and ref. 3, respectively) Position δ (natural) δ (synthetic 1, ±) δ (synthetic 1, ) (C 5 D 5 N, 150MHz) 2 (C 5 D 5 N, 125MHz) 3 (C 5 D 5 N, 200MHz) Δ 1 Δ 2 1 42.9 42.8 43.0 + 0.1 + 0.2 1* 44.8 44.7 44.9 + 0.1 + 0.2 2 208.9 208.7 208.9 + 0.0 + 0.2 2* 209.8 209.6 209.7 0.1 + 0.1 3 130.6 130.5 130.7 + 0.1 + 0.2 3* 131.2 131.1 131.3 + 0.1 + 0.2 4 180.2 180.0 180.2 + 0.0 + 0.2 4* 177.4 177.2 177.4 + 0.0 + 0.2 5 45.2 45.1 45.2 + 0.0 + 0.1 5* 44.8 44.6 44.8 + 0.0 + 0.2 6 80.5 80.4 80.6 + 0.1 + 0.2 6* 79.4 79.3 79.5 + 0.1 + 0.2 7 80.9 80.8 81.0 + 0.1 + 0.2 7* 80.3 80.2 80.4 + 0.1 + 0.2 8 31.4 31.3 31.4 + 0.0 + 0.1 8* 31.6 31.5 31.6 + 0.0 + 0.1 9 60.2 60.1 60.3 + 0.1 + 0.2 9* 60.2 61.3 61.5 + 1.3 + 0.2 10 105.9 105.8 106.0 + 0.1 + 0.2 10* 104.1 103.9 104.1 + 0.0 + 0.2 11 171.5 171.4 171.6 + 0.1 + 0.2 11* 169.2 169.0 169.2 + 0.0 + 0.2 12 178.9 178.8 179.0 + 0.1 + 0.2 12* 178.9 178.6 178.7 0.2 + 0.1 13 23.2 23.1 23.3 + 0.1 + 0.2 13* 23.1 23.0 23.2 + 0.1 + 0.2 14 76.0 75.9 76.1 + 0.1 + 0.2 14* 75.3 75.2 75.4 + 0.1 + 0.2 15 13.6 12.9 13.1 0.5 + 0.2 15* 14.5 14.4 14.5 + 0.0 + 0.1 CH 3 52.7 52.6 52.7 + 0.0 + 0.1 CH 3 * 52.0 51.9 52.0 + 0.0 + 0.1 7

Biological Assay Protocols: Rat PC-12M pheochromocytoma cells (obtained from the laboratories of Drs. Paul C. Sternweis, Elliott M. Ross and Joseph Goldstein; University of Texas Southwestern Medical Center) were cultured at a density of 2 x 10 4 cells/well in a 24-well plate in growth medium containing DMEM (Cellgro), 10% normal horse serum (Hyclone), 5% fetal calf serum (Gibco), 100 U/mL penicillin G, 100 µg/ml streptomycin sulfate (Cellgro) and incubated at 37ºC, 5% C 2. Four hours after plating, growth medium was replaced with differentiation medium (DMEM; 1% normal horse serum, 0.5% fetal calf serum) containing nerve growth factor (NGF, 50 ng/ml). After 24 hours of incubation, fresh differentiation medium was added containing NGF (50 ng/ml) with and without jiadifenin (0.3 or 0.5 µm, 1% DMS) and allowed to incubate an additional 48 hours. Triplicate wells were used for controls and experimental agents. Live cell images were obtained using a Leica EL6000 microscope (20X). Five regions with similar cell density from each well were selected for imaging. Cells from each well were photographed and analyzed, and from the data of the triplicate wells, the mean values were obtained. ne hundred cells or greater were examined from each well. The percentage of cells bearing neurites (more than two cell diameter in length) compared to total cells was calculated, and Student T test was used to check the P value against NGF with DMS control. Table 3. Effect of jiadifenin on the number of neurite-bearing cells Treatment Percentage (mean + SE, %) P value Controls (with NGF and 1% DMS) Controls (with NGF and without 1% DMS) jiadifenin (0.3 µm) with NGF and 1% DMS jiadifenin (0.5 µm) with NGF and 1% DMS 12.3 + 1.6 -- 15.6 + 1.4 0.025 21.1 + 3.5 < 0.001 28.0 + 1.5 < 0.001 8

Total neurite outgrowth length was measured by randomly selecting 15 neurons from the images of each treatment. The ratio was calculated by comparing the average neurite length found in the treatment to the NGF with 1% DMS control. Student T test was performed. Table 4. Effect of jiadifenin on the neurite outgrowth length Treatment Controls (with NGF and 1% DMS) Controls (with NGF and without 1% DMS) jiadifenin (0.3 µm) with NGF and 1% DMS jiadifenin (0.5 µm) with NGF and 1% DMS Average neurite length (mean + SE, arbitrary unit) Ratio P value 12.6 + 1.1 100% -- 13.3 + 1.2 106% < 0.01 18.7 + 2.2 148% < 0.001 21.6 + 3.1 172% < 0.001 [1] Xu, J.; Trzoss, L.; Chang, W. K.; Theodorakis, E. A. Angew. Chem. Int. Ed. 2011, 50, 3672 3676. [2] Yokoyama, R.; Huang, J.-M.; Yang, C.-S.; Fukuyama, Y. J. Nat. Prod. 2002, 65, 527 531. [3] (a) Cho, Y. S.; Carcache, D. A.; Tian, Y.; Li, Y.-M.; Danishefsky, S. J. J. Am. Chem. Soc. 2004, 126, 14358 14359; (b) Carcache, D. A.; Cho, Y. S.; Hua, Z.; Tian, Y.; Li, Y.-M.; Danishefsky, S. J. J. Am. Chem. Soc. 2006, 128, 1016 1022. 9

10 H 10

10 H 11

10 H 12

11 H 13

11 H 14

12 H 15

12 H 16

12 H 17

13 H 18

13 H 19

13 H 20

H 14 H 21

H 14 H 22

H 14 H 23

H C 2 Me H 1: ( )-jiadifenin 24

H C 2 Me H 1: ( )-jiadifenin 25