Synthesis, biological evaluations and molecular modelling of new. analogs of the anti-cancer agent

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1 Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 215 Synthesis, biological evaluations and molecular modelling of new analogs of the anti-cancer agent 2-methoxyestradiol: Potent inhibitors of angiogenesis Eirik Johansson Solum, a Jing-Jy Cheng, b,c,* Ingebrigt Sylte, d Anders Vik, a Trond Vidar ansen a,* a Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 168 Blindern, -316 Oslo, orway. b ational Research Institute of Chinese Medicine, Li-ung Street, Section 2, Shih-Pai, Taipei, Taiwan. c Institute of Biophotonics, ational Yang-Ming University, Taipei 112, Taiwan. d Department of Medical Biology, Faculty of ealth Sciences, UiT The Arctic University of orway, 937 Tromsø, orway. 2-Formylestradiol (1) 1 O O MgCl 2, Et 3, (C 2 O) n TF, O O O 9 1 To a solution of estradiol (9) (2.72 g, 1 mmol) in dry TF (1 ml), anhydrous MgCl 2 (2.85 g, 3 mmol), Et 3 (4.2 ml, 3 mmol), and paraformaldehyde (1.2 g, 4 mmol) were added under an argon atmosphere. After refluxing the mixture for 4 hours, TLC (hexane/etoac, 8:2) revealed complete consumption of 9, and the reaction mixture was cooled and quenched (1 M Cl, 5 ml). The aqueous phase was extracted with EtOAc (3x5 ml) and the combined organic phases were washed with brine and then dried (MgSO 4 ). The crude product was purified by flash chromatography (silica gel, 2% ethyl acetate in hexane, R f =,43) to give the pure product in 81% yield 2.44 g, mp C. 1 MR (3 Mz, CDCl 3 ) δ 1.77 (s, 1), 9.81 (s, 1), 7.42 (s, 1), 6.7 (s, 1), 3.74 (t, J = 8.4 z, 1), (m, 2), (m, 1), (m, 2), 1.95 (m, 1), (m, 1), (m, 1), (m, 8),.79 (s, 3). 13 C MR (11 Mz, CDCl 3 ) δ 196.2, 159.4, 148.2, 132.9, 13.7, 119.1, 117.1, 81.9, 5.2, 43.6, 43.4, 38.6, 36.6, 3.7, 3.3, 26.9, 26.4, 23.3, 11.2.

2 2-Allylestradiol (11) O O O MePPh 3 Br t-buoa TF O O 1 11 To a suspension of methyltriphenylphosphonium bromide (1 mmol, 5.9 g) in anhydrous TF (1 ml) at C under argon t-buoa (1 mmol, 1.6 g) was added. The suspension was stirred for 15-2 min at C to give a yellow solution. 2-Formylestradiol 1 ( mmol, 1.65 g) was added and the turbid mixture was stirred for 4 h at room temperature. A saturated ammonium chloride solution was added and the aqueous phase was extracted with DCM (3x2 ml). The combined organic layers were dried over MgSO 4, filtered and concentrated. The compound was purified by flash chromatography (silica gel, 2% ethyl acetate in hexane, R f =,43) to give the pure product in 84% yield 1.38 g, mp C. 1 MR (3 Mz, CDCl 3 ) δ 7.31 (s, 1), 6.91 (dd, J = 17.7, 11.2 z, 1), 4 (s, 1), 5.71 (dd, J = 17.7, 1.4 z, 1), 5.32 (dd, J = 11.2, 1.4 z, 1), 3.76 (t, J = 8.4 z, 1), (m, 2), (m, 1), (m, 2), (m, 1), (m, 1), (m, 1), (m, 9),.81 (s, 3). 13 C MR (11 Mz, CDCl 3 ) δ 15.9, 138.1, 133., 132.1, 124.4, 122.4, 115.9, 114.9, 82.1, 5.2, 44., 43.4, 39., 36.9, 3.8, 2, 27.3, 2, 23.3, Ethylestradiol (12) O O O 2, Pd/C EtOAc, rt. O A solution of 2-allylestradiol 11 (7.3 mmol, 2.1 g) in EtOAc (7 ml) was added at room temperature to a stirred solution Pd-C (1% (w/w)) in EtOAc. The resulting mixture was stirred under 2 gas under complete conversion of 11. Upon completion, 2 ml dichloromethane was added, and the reaction mixture was filtered through celite and washed with dichloromethane (3 x 3 ml). The combined filtrates were concentrated in vacuo, and the residue purified by flash chromatography (silica gel, 2% ethyl acetate in hexane, R f =.43) to give the pure 12 in 89% yield 1.95 g, mp C. 1 MR (4 Mz, CDCl 3 ) δ 7.6 (s, 1), (s, 1), 4.82 (s, 1), 3.75 (t, J = z, 1), (m, 2), 2.6 (q, J = z, 2), (m, 1), (m, 2), (m, 1), (m, 1), (m, 1), (m, 7), 1.23 (t, J = 7.6 z, 3),.79 (s, 3). 13 C MR (11 Mz, CDCl 3 ) δ 151.4, 135.6, 132.7, 127.4, 12, 115.3, 82.1, 5.2, 44.2, 43.4, 39.1, 36.9, 3.7, 29.4, 27.4, 26.6, 23.3, 23.2, 14.6, RMS calcd. for C 2 28 O 2 [M] Found

3 2-Ethylestrone (13) O cyclohexanone, Al(O-iPr) 3 O O toluene, O Ethylestradiol 12 (2.41 g, 8. mmol) was placed in a flame dried 25 ml two-necked roundbottomed flask equipped with a 5 ml flame dried Dean-Stark trap and a reflux condenser. Toluene (8 ml) was added to dissolve the starting material. Aluminum-iso-propoxide (8.17 g, 4 mmol) and cyclohexanone (33.1 ml, 32 mmol) were added, and the reaction mixture was heated at reflux (145 C) for 2 h. The reaction mixture was allowed to cool to room temperature. Then water (1 ml) and 1 M Cl (45 ml) were added. The organic material was extracted with ethyl acetate (3 x 15 ml). The aqueous emulsion was acidified with 1 M Cl (5 ml) and left until the emulsion separated. The aqueous layer was extracted once more with ethyl acetate (1 ml). The combined organic extracts were dried (MgSO 4 ) and evaporated in vacuo. The residue was triturated with hexane to give 13, as white crystals in 75% yield 1.79 g, mp C. 1 MR (4 Mz, CDCl 3 ) δ 7.6 (s, 1), 2 (s, 1), 4.73 (s, 1), (m, 2), 2.6 (q, J = z, 2), (m, 1), (m, 1), (m, 1), (m, 1), (m, 3), (m, 6), 1.23 (t, J = z, 3),.92 (s, 3). 13 C MR (11 Mz, CDCl 3 ) δ 221.4, 15, 135.3, 132.1, 12, 12, 115.4, 5.6, 48.2, 44.2, 38.6, 36.1, 31.8, 29.2, 26.7, 26.2, 23.2, 21.7, 1, 14.. RMS calcd. for C 2 26 O 2 [M] Found tert-Butyldimethylsiloxy-2-ethylestrone (14) O O O TBS-Cl imidazole, DMF Ethylestrone 13 (1 g, 5. mmol) was placed in a 1 ml round bottomed flask and dissolved in dry DMF (25 ml). Imidazole (.85 g, 1 mmol) and TBSCl (1.13 g, mmol) were added. The reaction mixture was stirred at room temperature under argon atmosphere for 5 h. Saturated aqueous acl (2 ml) was added, and the mixture was extracted with ethyl acetate (3 x 2 ml). The combined organic extracts were washed with brine (1 ml), aqueous AcO (1%, 1 ml) and aqueous aco 3 (1 ml) before it was dried (MgSO 4 ) and evaporated in vacuo. The product was purified by flash chromatography (silica gel, 2% ethyl acetate in hexane, R f =,43)

4 to give 14 as a colorless oil in 93% yield (1.93 g). [α] D = - 19 (c =.1, MeO). 1 MR (4 Mz, CDCl 3 ) δ 7.6 (s, 1), (s, 1), (m, 2), 7 (q, J = 7.6 z, 2), (m, 1), 2.43 (d, J = 11.9 z, 1), 2.24 (dd, J = 13.6, 7. z, 1), 2.11 (d, J = 8.6 z, 1), (m, 3), (m, 6), 1.17 (t, J = z, 3), 1.2 (s, 9),.92 (s, 3),.23 (s, 6). 13 C MR (11 Mz, CDCl 3 ) δ 221.1, 15, 134.7, 132.2, 132.1, 126.4, 118.4, 5.6, 48.2, 44.3, 38.6, 36., 31.8, 29.4, 26.8, 26.1, 25.9, 23.7, 21.8, 14.8, 14., -4., -4.. (8R,9S,13S,14S)-3-((tert-butyldimethylsilyl)oxy)-2-ethyl-13-methyl-7,8,9,11,12,13,14,15- octahydro-6-cyclopenta[a]phenanthren-17-yl trifluoromethanesulfonate (15) O KMDS, Ph(SO 2 CF 3 ) TF TBS protected 2-ethylestrone 14 (861 mg, mmol) and -Phenylbis(trifluoromethanesulfonimide) (1.34 g, 3.75 mmol) were dissolved in dry TF (5 ml) and cooled to -78 C. amds (1 ml.6 M in toluene, mmol), was added dropwise at 78 C and the resulting mixture was stirred at -78 C for 3 h. Then the reaction was brought to room temperature and quenched by addition of saturated aqueous 4 Cl (2 ml). The mixture was extracted with C 2 Cl 2 (2 x 15 ml); the combined organic extracts were washed with water and brine, dried (MgSO 4 ) and concentrated in vacuo. The residue was purified by flash chromatography (silica gel, 2% ethyl acetate in hexane, R f =,64) to give 1,39 g of 15 as a colorless oil (81% yield). 1 MR (3 Mz, CDCl 3 ) δ 7.3 (s, 1), (s, 1), 5.62 (dd, J = 3.2, 1.6 z, 1), (m, 2), 8 (q, J = z, 2), (m, 3), (m, 1), (m, 2), (m, 1), (m, 3), (m, 1), 1.18 (t, J = z, 3), 1.2 (s, 9), 1.2 (s, 3),.24 (s, 6). 13 C MR (11 Mz, CDCl 3 ) δ 159.6, 15, 134.6, 132.3, 132.2, 126., 11, 114.6, 53.8, 45.3, 4, 36.9, 33., 29.2, 2, 27., 26., 25.9, 23.8, 18.4, 1, 14.8, -4., -4.. OTf General procedure for the Suzuki cross-coupling reaction and synthesis of (16a-e) OTf ArB(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 Ar TF : 2 O 15 16a-e The TBS protected steroid triflate 15 (.5 mmol, 1 equiv.), cesium carbonate (2 equiv.) and the boronic acid ( equiv.) was placed in a flame dried 5 ml round-bottomed flask under argon

5 atmosphere and dissolved in a 1:1 mixture of water and TF. Pd(PPh 3 ) 4 (5 mol%) was added and the reaction mixture was stirred at room temperature (18 22 h.). Upon completion the reaction mixture was poured into brine (15 ml) and extracted with ethyl acetate (4 x 5 ml). The combined organic extracts were dried (MgSO 4 ) and the solvent evaporated in vacuo. The residue was purified by flash chromatography (silica gel, 2-2% ethyl acetate in hexane) to give the pure products. tert-butyl(((8s,9s,13s,14s)-2-ethyl-13-methyl-17-phenyl-7,8,9,11,12,13,14,15-octahydro-6cyclopenta[a]phenanthren-3-yl)oxy)dimethylsilane (16a) OTf PhB(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 TF : 2 O 15 16a 1 MR (3 Mz, CDCl 3 ) δ 7.41 (dd, J = 8.3, 1.3 z, 2), (m, 2), (m, 1), 7.6 (s, 1), 1 (s, 1), 5.94 (dd, J = 3.2, 1.7 z, 1), 2.84 (s, 2), 8 (q, J = z, 2), (m, 3), 2.25 (m, 2), (m, 1), (m, 1), (m, 2), (m, 2), 1.18 (t, J = z, 3), 1.7 (s, 3), 1.2 (s, 9), (m, 6). 13 C MR (11 Mz, CDCl 3 ) δ 155.2, 151.3, 13, 135., 133., 132., 128.3, 127.2, 126.9, 126.1, 118.4, 57.1, 47.8, 44.4, 37.6, 35.7, 3, 2, 28., 26.8, 25.9, 23.8, 18.4, 17., 14.9, -3.9, -4.. Eluent 2% EtOAc in hexane R f =.59, yield 173 mg, 73%, product colorless oil. 3-((8S,9S,13S,14S)-3-((tert-butyldimethylsilyl)oxy)-2-ethyl-13-methyl-7,8,9,11,12,13,14,15- octahydro-6-cyclopenta[a]phenanthren-17-yl)pyridine (16b) OTf B(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 TF : 2 O 15 16b 1 MR (4 Mz, CDCl 3 ) δ 4 (s, 1), 8.35 (d, J = 4.7 z, 1), 7.6 (d, J = 7.9 z, 1), 7.14 (dd, J = 9., 6.3 z, 1), 6.94 (s, 1), 6.39 (s, 1), 5.92 (s, 1), (m, 2), 2.46 (q, J = z, 2), (m, 3), (m, 2), (m, 1), (m, 1), (m, 3), (m, 1), 1.6 (t, J = z, 3),.93 (s, 3),.9 (s, 9),.12 (s, 6). 13 C MR (11 Mz, CDCl 3 ) δ 151.7, 151.3, 147.3, 134.7, 134.2, 133.3, 132.6,

6 131.9, 12, 125.9, 123.3, 123.3, 118.3, 56.8, 47.8, 44.2, 37.4, 35.4, 31.6, 29.3, 27.9, 2, 25.8, 23.7, 18.3, 16.8, 14.8, -4.1, Eluent 2% EtOAc in hexane R f =.26, yield 192 mg, 81%, product colorless oil. 4-((8S,9S,13S,14S)-3-((tert-butyldimethylsilyl)oxy)-2-ethyl-13-methyl-7,8,9,11,12,13,14,15- octahydro-6-cyclopenta[a]phenanthren-17-yl)pyridine (16c) OTf B(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 TF : 2 O 15 16c 1 MR (4 Mz, CDCl 3 ) δ 3 (d, J = 6.2 z, 2), (m, 2), 7.6 (s, 1), 2 (s, 1), 6.22 (dd, J = 3.2, 1.8 z, 1), (m, 2), 9 (q, J = z, 2), (m, 5), (m, 1), (m, 1), 1.68 (t, J = 1.7 z, 3), (m, 1), 1.19 (t, J = z, 3), 1.9 (s, 3), 1.3 (s, 9),.25 (d, J = 1.4 z, 6). 13 C MR (11 Mz, CDCl 3 ) δ 152.7, 151.3, 149.4, 144.9, 134.7, 13, 132., 131.7, 125.9, 121.2, 118.3, 56.8, 47.6, 44.2, 37.3, 35.3, 31.6, 29.3, 27.8, 2, 25.8, 23.6, 18.2, 16.8, 14.7, -4.1, Eluent 2% EtOAc in hexane R f =.27, yield 185 mg, 78%, product colorless oil. 4-((8S,9S,13S,14S)-3-((tert-butyldimethylsilyl)oxy)-2-ethyl-13-methyl-7,8,9,11,12,13,14,15- octahydro-6-cyclopenta[a]phenanthren-17-yl)isoquinoline (16d) OTf B(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 TF : 2 O 15 16d 1 MR (4 Mz, CDCl 3 ) δ (s, 1), 8.22 (s, 1), 8. (d, J = z, 1), 7.9 (d, J = 8.1 z, 1), 7.63 (t, J = 7.6 z, 1), 3 (t, J = z, 1), 6.93 (s, 1), 6.42 (s, 1), 5.81 (s, 1), (m, 2), 2.47 (q, J = 7.4 z, 2), (m, 1), (m, 3), 1.84 (m, 2), (m, 2), (m, 3), 1.6 (t, J = z, 3),.91 (s, 12),.14 (s, 6). 13 C MR (11 Mz, CDCl 3 ) δ 151.7, 151.3, 147.3, 147.3, 135.7, 134.7, 134.2, 133.3, 132.6, 131.9, 12, 129.4, 126.4, 125.9, 123.3, 123.3, 118.3, 56.8, 47.8, 44.2, 37.4, 35.4,

7 31.6, 29.3, 27.9, 2, 25.8, 23.7, 18.3, 16.8, 14.8, -4.1, Eluent 2% EtOAc in hexane R f =.34, yield 22 mg, 84%, product light yellow oil. 5-((8S,9S,13S,14S)-3-((tert-butyldimethylsilyl)oxy)-2-ethyl-13-methyl-7,8,9,11,12,13,14,15- octahydro-6-cyclopenta[a]phenanthren-17-yl)isoquinoline (16e) OTf B(O) 2, Cs 2 CO 3, Pd(PPh 3 ) 4 TF : 2 O 15 16e 1 MR (4 Mz, CDCl 3 ) δ 9.25 (s, 1), 1 (d, J = 6. z, 1), (m, 2), (m, 2), 7.2 (s, 1), 2 (s, 1), 5.84 (dd, J = 3., z, 1), 2.89 (dd, J = 16.4, 9.2 z, 2), (m, 2), (m, 1), (m, 3), 2.1 (tt, J = 11.4, 6.3 z, 2), 1.72 (t, J = 12.3 z, 2), (m, 3), 1.16 (t, J = z, 3), 1.2 (s, 12),.24 (s, 6). 13 C MR (11 Mz, CDCl 3 ) δ 152.7, 15, 151.4, 143., 135.6, 135.2, 134.9, 132.7, 132., 13.9, 129.7, 129.2, 126.7, 12, 126.1, 119.4, 118.4, 56.9, 5.1, 44.6, 37.9, 35.4, 32.2, 2, 28.2, 26.6, 25.9, 23.8, 18.4, 16.7, 14.9, -4., -4.. Eluent 2% EtOAc in hexane R f =.31, yield 196 mg (75%), product colorless oil.

8 O O O 1 O O O 1

9 O O 11 O O 11

10 O O 12 O O 12

11 O O 13 O O 13

12 O 14 O 14

13 OTf 15 OTf 15

14 a 16a

15 b 16b

16 c 16c

17 d 16d

18 e 16e

19 O 7a O 7a

20 O 7b O 7b

21 O 7c O 7c

22 O 7d O 7d

23 O 7e O 7e

24 O 2 SO 8a 2 O 2 SO 8a

25 O 2 SO 8b 2 O 2 SO 8b

26 O 2 SO 8c 2 O 2 SO 8c

27 O 2 SO 8d 2 O 2 SO 8d

28 O 2 SO 8e 2 O 2 SO 8e

29 Determination of inhibition of tubulin polymerization data The polymerization curve was made as OD of each sample (Y axis) vs time (X axis). The AUC (area under curve) between zero to 3 minutes was obtained to present the polymerization degree. The final concentration of each compound tested was.625,.25, 1, 4 and 1 μμ. The AUC (area under curve) between zero to 3 minutes was obtained to present the polymerization degree using Sigmaplot software. After AUC was obtained, the average AUC was calculated with the equation was shown as below to get the inhibition percentage. We set colchicine as 1% inhibition and paclitaxel as %. Inhibition rate = Sample (paclitaxel)/sample (colchicine - paclitaxel) x 1% The IC 5 value was calculated after obtaining the curve equation of inhibition % (Y axis) and concentration (x axis) using Excel. Compound 8a is shown as an example: Reference: (1) Akselsen, O. W.; ansen, T. V. Tetrahedron 211, 67, 7738.