Design, Synthesis and Evaluation of a Series of Novel Benzocyclobutene Derivatives as General Anesthetics

Transcription

1 Design, Synthesis and Evaluation of a Series of Novel Benzocyclobutene Derivatives as General Anesthetics Chen Zhang*, Fangqiong Li, Yan Yu, Anbang Huang, Ping He, Ming Lei, Jianmin Wang, Longbin Huang, Zhenhong Liu, Jianyu Liu, and Yonggang Wei Haisco Pharmaceutical Group Co. Ltd., 136 Baili Road, Wenjiang district, Chengdu , China Supporting information 1 / 40

2 Contents General In Vivo Biology Information Binding Assay Rat PK Study Information General Chemistry Information X-ray crystallography S3 S3 S3 S5 S28 2 / 40

3 General In Vivo Biology Information In Vivo Loss of Righting Reflex (LORR) Assays on Mice. The on-set and duration time of anesthesia effect of benzocyclobutene derivatives was evaluated through the experiment of loss of righting reflex (LORR) using a validated rodent model of general anesthesia(hill-venning C. et al., Neurpharmacology 1996, 35, 1209). The tested compounds were formulated with 5% of dimethyl sulfoxide, 5 10% of Solutol HS-15, and 85 90% of saline. The fasted ICR mice were randomly divided into 7 9 dosage groups, each dosage group had 10 ICR mice, and the mice were administered a single intravenous bolus injection in clear or emulsion solution in the lateral tail vein, which took approximately 10 s. Anesthetic effects were assessed using (1) onset of LORR, as measured by the time from dosing to LORR, and (2) LORR duration as measured by the time from dosing to recovery of fighting reflex. Nonlinear fitting using GraphPad Prism5 was applied to calculated ED 50 and LD 50 values. Therapeutic index (TI) was calculated by LD 50 divided by ED 50. A high TI is preferable to have a favorable safety profile. The duration time of the tested compounds corresponds to the dosage that could produce 100% LORR in the mice. Binding Assay A radioligand binding assay method was utilized to evaluate the GABA A receptor binding ability of compounds 1a, 1b, 16a, and 16b. According to Maksay and Simonyi, crude synaptosomal membranes of cerebral cortex of male Wistar rats were prepared for this study, and then, membrane suspension in 20 mm Tris-HCl (ph 7.4) containing 200 mm NaCl was preincubated with 2.0 nm [ 35 S]TBPS at 25. After 3 h, the suspension was filtered under reduced pressure and washed with ice-cold buffer (3 3 ml). The radioactivity of the filters was measured in a scintillation counter. Nonspecific binding of the test compound was measured with 200 M picrotoxin. GABA A receptor binding assays of the tested compounds were obtained and expressed as the percent inhibition of control specific TBPS binding. Rat PK Study Information Drug naive adult male Sprague-Dawley rats were administered a single dose administration of the test article by intravenous (IV) dose routes. Testing Facility and Test Site: 3D BioOptima, Co. Ltd., 1338 Wuzhong Blvd., Suzhou, , P.R. China TEST ARTICLE AND VEHICLE INFORMATION: IV dosing vehicles: DMA+30% Solutol HS-15(w/v)+saline=10%+20%+70% Typical Dose formulation: 1) Precisely weigh 2.08 mg H2474 into a glass vial. 2) Add 1.04 ml DMA, vortex to solution. 3) Add 2.08 ml Solutol HS-15 (30%,w/v) while vortexing. 4) Add 7.28 ml saline while vortexing. 5) Filtrate the resulting solution with 0.22 µm PTFE membrane. 6) Pipette 50 μl of dose formulation into 1.5 ml EP tube for dose determination. 3 / 40

4 TEST SYSTEM: Species and strain: Rat; male Sprague Dawley Supplier: Vital River Laboratories Animal Co. LTD Weight range: g Number: 6 animals EXPERIMENTAL DESIGN: Group Assignment: Three animals were assigned to each dose group (Group 1 and Group 2) for each PK experiment for compounds 1a & 1b as indicated in Table 3. Administration: 1 mg kg ¹ (0.2 mg ml ¹) was administered via tail vein injection (n = 3). Sample Collection: The animal was restrained manually at the designated time points, approximately 150 µl of blood sample was collected via jugular vein into dried heparinized (coated with 0.25 % heparin in saline) tubes. Sample Processing: Blood samples were centrifuged at 5500 rpm for 10 min to obtain plasma samples. 4 / 40

5 General Chemistry Information General Information: All purchased starting materials were used without further purification. Proton nuclear magnetic resonance spectra ( 1 H-NMR) were acquired on a Bruker Avance-400 spectrometer (400 MHz) or a Bruker Avance-300 spectrometer (300 MHz), with tetramethylsilane (TMS) as an internal standard; chemical shifts are expressed in parts per million (ppm, δ units). Data are reported as app = apparent, s = singlet, d = doublet, t = triplet, q = quartet, hept = heptet, m = multiplet, br = broad, coupling constant(s) are in Hz. Proton-decoupled carbon nuclear magnetic resonance spectra ( 13 C NMR) spectra were recorded on a Bruker Avance-400 spectrometer (400 MHz) or a Bruker Avance-300 spectrometer (300 MHz), with tetramethylsilane (TMS) as an internal standard; chemical shifts are expressed in parts per million (ppm, δ units). Melting points were recorded on an OptiMelt automated melting point system and are uncorrected. Mass spectra were obtained on a FinniganLCQAd instrument (ESI). Most masses were reported as those of the protonated parent ions. Preparative column chromatography was performed using YantaiHuanghai mesh silica. CLogP values of the title compounds were calculated by Chemdraw/CLogP(Biobyte). Purities of title compounds were 95% by HPLC. Synthesis of compound 26a: 2-Bromo-6-isopropylphenol (23a). To a stirred solution of 2-isopropyl phenol (10.0 g, mmol) and diisopropylamine (0.74 g, 7.3 mmol) in 200 ml of dichloromethane was added N-bromosuccinimide (13.07 g,220 mmol) at 0. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with HCl (3.0 M, 100 ml), extracted with dichloromethane (150 ml 3) and dried with sodium sulfate. The solvent was removed under reduced pressure. The title compound was obtained as a yellow oil (15.0 g) in 95% yield. 1 H NMR (300 MHz, CDCl 3 ): δ 7.31 (d, J = 8.0 Hz, 1H), 7.16 (d, J = 7.7 Hz, 1H), 6.79 (t, J = 7.8 Hz, 1H), 5.57 (br s, 1H), 3.34 (hept, J = 6.9 Hz, 1H), 1.25 (d, J = 6.9 Hz, 6H). 2-(Benzyloxy)-1-bromo-3-isopropylbenzene (24a). To a stirred solution of 2-bromo-6- isopropylphenol(23a, 5.0g, mmol) and potassium carbonate(6.44 g, 46.6 mmol) in 1000 ml of acetonitrile was added benzyl bromide (3.97 g,23.21 mmol). Subsequent to the addition, the reaction mixture was refluxed for 2 h. The resulting solution was quenched with Et 2 O (100 ml) 5 / 40

6 and filtered. The filtrate was removed under reduced pressure and the title compound was obtained as a colorless oil (6.46 g) in 91.1% yield. 1 H NMR (300 MHz, CDCl 3 ): δ (m, 6H), 7.22 (d, J = 7.8 Hz, 1H), 6.99 (t, J = 7.8 Hz, 1H), 4.96 (s, 2H), (hept, J = 7.1 Hz, 1H), 1.19 (d, J = 7.1 Hz, 6H) 1,1-Diethoxyethene (25). To a stirred solution of potassium tert-butoxide(34.2 ml, mmol) and 18-crown-6 (1.59 g, 6 mmol) in 200 ml of THF was added 2-bromo-1,1-diethoxyethane(58.8 g, mmol) at 0. The reaction mixture was maintained at 0 and stirred for 2 h. The title compound was distilled under reduced pressure as colorless oil (15 g) in 43.3% yield. 1 H NMR (400 MHz, CDCl 3 ): δ 3.83 (m, J = 7.0 Hz, 4H), 3.04 (s, 2H), 1.33 (t, J = 7.0 Hz, 6H). 5-Benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26a). To a stirred solution of 2-(benzyloxy)-1-bromo-3-isopropylbenzene(24a, 19.76g, mmol) and sodium amide (5.04 g, mmol) in 250 ml of THF was added 1,1-diethoxyethene (25, 15.0 g, mmol) under nitrogen. Subsequent to the addition, the reaction mixture was refluxed for 15 h. The reaction mixture was cooled down to room temperature, poured into ice-water (100 ml), acidified with HCl (conc, 30 ml), extracted with ethyl acetate (200 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:50 ethyl acetate/hexanes). The title compound was obtained as a yellow oil (8.5 g) in 49% yield. R f =0.15 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (300 MHz, CDCl 3 ): δ (m, 6H), 7.02 (d, J = 7.3 Hz, 1H), 5.50 (s, 2H), 3.88 (s, 2H), 3.37 (hept, J = 7.0 Hz, 1H), 1.21 (d, J = 7.0 Hz, 6H). Synthesis of compound 1: 6-(Benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a). To a stirred solution of 5-benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one(26a, 3.00 g, mmol) in 30 ml of dry THF was added dropwise methyl magnesium bromide(1.0 M, 13.5 ml, mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (30 ml), extracted with ethyl acetate (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate). The title compound was obtained as a yellow solid (910 mg) in 28% yield. R f =0.21 (1:20 ethyl acetate/hexanes, TLC). 6 / 40

7 1 H NMR (400 MHz, CDCl 3 ) δ (m, 5H), 7.20 (d, J = 7.4 Hz, 1H), 6.76 (d, J = 7.4 Hz, 1H), 5.41 (d, J = 11.8 Hz, 1H), 5.28 (d, J = 11.8 Hz, 1H), (m, 1H), 3.32 (d, J = 14.0 Hz, 1H), 3.16 (d, J = 14.0 Hz, 1H), 1.78 (s, 3H), (m, 6H). 6-(Benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzene (28a). To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a, 3.50 g, mmol) and triethylsilane (1.72 g,14.80 mmol) in 40 ml of dichloromethane was added dropwise boron trifluoride etherate (2.11 g, mmol) at 0. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 1 hr. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (30 ml), extracted with dichloromethane (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as a yellow solid (1.97 g) in 59.7% yield. R f =0.55 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (300 MHz, CDCl 3 ): δ (m, 5H), 7.11 (d, J = 7.0 Hz, 1H), 6.70 (d, J = 6.8 Hz, 1H), 5.23 (d, J = 11.3 Hz, 1H), 5.12 (d, J = 11.3 Hz, 1H), (m, 1H), (m, 2H), (m, 1H), 1.53 (d, J = 6.5 Hz, 3H), (m, 6H). 4-Isopropyl-7-methyl-bicyclo[4.2.0]octa-1,3,5-trien-5-ol (1). To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzene (28a, 1.80 g,6.75 mmol) in 100 ml of methanol was added Pd/C (0.14 g, 10 wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:20 ethyl acetate/hexanes). The title compound was obtained as colorless oil (1.04 g) in 87.3% yield. clogp compd1 = R f =0.20 (1:20 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 12 H 17 O [M + H] Found: H NMR (400 MHz, CDCl 3 ): δ 7.05 (d, J = 7.4 Hz, 1H), 6.65 (d, J = 7.4 Hz, 1H), 4.42 (br s, 1H), (m, 1H), 3.28 (dd, J = 13.8, 5.3 Hz, 1H), 3.18(hept, J = 6.9 Hz, 1H), 2.58 (dd, J = 13.7, 2.4 Hz, 1H), 1.41 (d, J = 7.0 Hz, 3H), 1.25 (d, J = 6.9 Hz, 3H), 1.23 (d, J = 6.9 Hz, 3H) 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 35.33, 34.12, 25.29, 21.42, 21.26, Synthesis of compound 2: 5-Benzyloxy-7-ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27b). To a stirred solution of 5-benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26a, 10.0 g, mmol) in / 40

8 ml of dry THF was added dropwise ethylmagnesium bromide(1.0 M, 45.0 ml, 45.0 mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 1hr. The reaction mixture was quenched with a saturated solution of ammonium chloride (100 ml), extracted with ethyl acetate (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate). The title compound was obtained as a yellow oil (6.77 g) in 60.8% yield. R f =0.23 (1:20 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl 3 ) δ 7.45 (d, J = 7.2 Hz, 2H), (m, 2H), (m, 1H), 7.19 (d, J = 7.4 Hz, 1H), 6.75 (d, J = 7.4 Hz, 1H), 5.32 (d, J = 11.7 Hz, 1H), 5.24 (d, J = 11.7 Hz, 1H), (m, 2H), 3.00 (d, J = 14.1 Hz, 1H), 2.26 (br s, 1H), (m, 1H), (m, 1H), 1.21 (d, J = 6.9 Hz, 3H), 1.18 (d, J = 6.9 Hz, 3H), 0.99 (t, J = 7.4 Hz, 3H). 5-Benzyloxy-7-ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-triene (28b). To a stirred solution of 5-benzyloxy-7-ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27b, 4.50 g, mmol) and triethylsilane (2.12 g,18.23 mmol) in 100 ml of dichloromethane was added dropwise boron trifluoride etherate (2.59 g, mmol) at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 0.5 hr. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (50 ml), extracted with dichloromethane (100 ml 2) and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as a yellow solid (3.30 g) in 64.6% yield. R f =0.56 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (300 MHz, CDCl 3 ): δ (m, 5H), 7.15 (d, J = 7.4 Hz, 1H), 6.75 (d, J = 7.6 Hz, 1H), 5.27 (d, J = 11.6 Hz, 1H), 5.12 (d, J = 11.6 Hz, 1H), (m, 1H), 3.41(hept, J = 7.0 Hz, 1H), 3.29 (dd, J = 13.9, 5.3 Hz, 1H), 2.74 (d, J = 13.9 Hz, 1H), (m, 1H), (m, 1H), (m, 6H), 1.06 (t, J = 7.4 Hz,3H). 7-Ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-5-ol (Compound 2). To a stirred solution of 5-benzyloxy-7-ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-triene (28b, 3.30 g, mmol) in 100 ml of methanol was added Pd/C (0.25 g, 10wt%).The mixture was stirred under a hydrogen atmosphere at room temperature for 3 h. The resulting solution was filtered. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:30 ethyl acetate/hexanes). The title compound was obtained as yellow oil (1.50 g) in 67.0% yield. clogp compd2 = R f =0.21 (1:30 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 13 H 17 O [M H] Found: H NMR (400 MHz, CDCl 3 ): δ 7.07 (d, J = 7.4 Hz, 1H), 6.68 (d, J = 7.4 Hz, 1H), 4.58 (br s, 1H), (m, 1H), (m, 2H), (m, 1H), (m, 1H), (m, 1H), 1.25 (app, t, J = 6.9 Hz, 6H), 1.09 (t, J = 7.3 Hz, 3H). 8 / 40

9 Synthesis of compound 3: 5-(Benzyloxy)-7-cyclopropyl-4-isopropylbicyclo[4.2.0]octa-1,3,5-trien-7-ol (27c). To a stirred solution of 5-benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26a, 6.0 g, mmol) in 150 ml of dry THF was added dropwise cyclopropylmagnesium bromide (1.0 M, 35.0 ml, 35.0 mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 3 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (200 ml), extracted with ethyl acetate (100 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as yellow oil (2.7 g) in 39.0% yield. R f =0.23 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl 3 ) δ (m, 2H), (m, 2H), (m, 1H), 7.19 (d, J = 7.4 Hz, 1H), 6.75 (d, J = 7.4 Hz, 1H), 5.45 (d, J = 11.9 Hz, 1H), 5.32 (d, J = 11.9 Hz, 1H), 3.39 (hept, J = 7.0 Hz, 1H), 3.22 (d, J = 14.1 Hz, 1H), 3.00 (d, J = 14.1 Hz, 1H), 2.37 (s, 1H), (m, 1H), (m, 6H), (m, 2H), (m, 2H). 2-(Benzyloxy)-8-cyclopropyl-3-isopropylbicyclo[4.2.0]octa-1,3,5-triene (28c). To a stirred solution of 5-(benzyloxy)-7-cyclopropyl-4-isopropylbicyclo[4.2.0]octa-1,3,5-trien-7-ol (27c, 0.7 g, 2.27 mmol) and triethylsilane (12.28 g,105.6 mmol) in 30 ml of dichloromethane was added dropwise trifluoroacetic acid (2.5 ml, 32 mmol) at 0. Subsequent to the addition, the reaction mixture was maintained at 0 and stirred for 2 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (60 ml), extracted with dichloromethane (60 ml 2) and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (30:1 hexanes/ethyl acetate). The title compound was obtained as colorless oil (0.45 g) in 74% yield. R f =0.52 (1:30 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl 3 ) δ 7.45 (d, J = 7.2 Hz, 2H), (m, 2H), (m, 1H), 7.13 (d, J = 7.4 Hz, 1H), 6.71 (d, J = 7.4 Hz, 1H), 5.49(d, J = 11.2 Hz, 1H), 5.19(d, J = 11.2 Hz, 1H),, 3.39 (hept, J = 6.9 Hz, 1H), 3.26 (dd, J = 13.8, 5.5 Hz, 1H), 3.16 (ddd, J = 8.3, 5.5, 2.4 Hz, 1H), 2.83 (dd, J = 13.8, 2.5 Hz, 1H), (m, 7H), (m, 1H), (m, 1H), (m, 1H), (m,1h). 8-Cyclopropyl-3-isopropylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 3). To a stirred solution of 2-(benzyloxy)-8-cyclopropyl-3-isopropylbicyclo[4.2.0]octa-1,3,5-triene (28c, 0.45 g, 9 / 40

10 1.54 mmol) and potassium carbonate (0.21 g, 1.54 mmol) in 45 ml of ethyl acetate was added Pd/C (45mg, 10wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 3 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with ethyl acetate (30 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:60 ethyl acetate/hexanes). The title compound was obtained as a yellow solid (265 mg) in 85% yield. clogp compd3 = Mp: R f =0.22 (1:60 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 14 H 17 O [M H] Found: H NMR (400 MHz, CDCl 3 ) δ 7.08 (d, J = 7.4 Hz, 1H), 6.67 (d, J = 7.4 Hz, 1H), 4.52 (s, 1H), (m, 2H), (m, 1H), 2.84 (dd, J = 13.8, 2.5 Hz, 1H), 1.25 (d, J = 6.9 Hz, 3H), 1.23 (d, J = 6.9 Hz, 3H), (m, 1H), (m, 2H), (m, 1H), (m, 1H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 45.86, 35.32, 27.14, 23.09, 22.85, 14.20, 4.42, Synthesis of compound 4: 5-Isopropyl-1,2-dihydrocyclobutabenzene-1,6-diol (Compound 4). To a stirred solution of 5-hydroxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (Compound 5, 0.58 g, 3.29 mmol) in 15 ml of methanol was added sodium borohydride (0.25 g, 6.41 mmol). The mixture was stirred at room temperature for 0.5 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (4.0 ml), extracted with dichloromethane (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:15 ethyl acetate/hexanes). The title compound was obtained as a white solid (350 mg) in 59.7% yield. clogp compd4 = R f =0.18 (1:15 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 11 H 13 O 2 [M H] Found: H NMR (400 MHz, DMSO-d 6 ): δ 9.22(s, 1H), 7.02 (d, J = 7.3 Hz, 1H), 6.55 (d, J = 7.3 Hz, 1H), 5.31 (d, J = 6.5 Hz, 1H), 5.08 (ddd, J = 6.5, 4.5, 1.8 Hz, 1H), 3.28 (dd, J = 13.6, 4.5 Hz, 1H), 3.17 (hept, J = 7.0 Hz, 1H), 2.72 (dd, J = 13.6, 1.8 Hz, 1H), 1.12 (d, J = 7.0 Hz, 6H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 69.53, 41.22, 26.84, 22.95, / 40

11 Synthesis of compound 5: 5-Hydroxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (Compound 5). To a stirred solution of 5-benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26a, 3.50g, mmol) in 70 ml of methanol was added Pd/C (2.1 g, 10 wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 1.5 h. The resulting solution was filtered. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:15 ethyl acetate/hexanes). The title compound was obtained as a white solid (1.23 g) in 53.1% yield. clogp compd5 = Mp: R f =0.25 (1:15 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 11 H 11 O 2 [M H] Found: H NMR (300 MHz, CDCl 3 ) : δ 7.77 (s, 1H), 7.42 (d, J = 7.3 Hz, 1H), 7.00 (d, J = 7.3 Hz, 1H), 3.87 (s, 2H), 3.31 (hept, J = 6.9 Hz, 1H), 1.23 (d, J = 6.9 Hz, 6H). Synthesis of compound 6: 1-Benzyloxy-2-bromo-benzene (24c). To a stirred solution of 2-bromophenol (23c, 30.0g, mmol) and potassium carbonate (47.7 g, 346 mmol) in 300 ml of acetonitrile was added benzyl bromide (29.7 g, mmol). Subsequent to the addition, the reaction mixture was refluxed for 3 h. The resulting solution was quenched with H 2 O (800 ml), extracted with hexanes (800 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure and the title compound was obtained as a colorless oil (45.1g) in 100% yield. 5-Benzyloxybicyclo[4.2.0]octa-1,3,5-trien-7-one (26c). To a stirred solution of 1-benzyloxy-2- bromo-benzene (24c, 10.0g, mmol) and sodium amide (2.96 g, mmol) in 100 ml of THF was added 1,1-diethoxyethene (25, 8.82 g, mmol) under nitrogen. Subsequent to the addition, the reaction mixture was refluxed for 12 h. The reaction mixture was poured into ice-water, acidified with conc. HCl, extracted with ethyl acetate (100 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:50 ethyl acetate/hexanes). The title compound was obtained as a white solid (5.3g) in 73% yield. R f =0.54 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl 3 ) δ (m, 6H), (d, J = 7.0 Hz, 1H), (d, 11 / 40

12 J = 7.0 Hz,1H), 5.46 (s, 2H), 3.94 (s, 2H). 5-Benzyloxy-7-methyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27d). To a stirred solution of 5-benzyloxybicyclo[4.2.0]octa-1,3,5-trien-7-one (26c, 5.1 g, mmol) in 100 ml of dry THF was added dropwise methylmagnesium bromide(2.0 M, 13.5 ml, mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (100 ml), extracted with ethyl acetate (100 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate). The title compound was obtained as a white solid (4.02g) in 74% yield. R f =0.31 (1:20 ethyl acetate/hexanes, TLC). 5-Benzyloxy-7-methyl-bicyclo[4.2.0]octa-1,3,5-triene (28d). To a stirred solution of 5-benzyloxy-7- methyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27d, 3.71 g, mmol) and triethylsilane (2.15 g, mmol) in 70 ml of dichloromethane was added dropwise boron trifluoride etherate (2.63 g, mmol) at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (30 ml), extracted with dichloromethane (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as colorless oil (3.17g) in 92% yield. R f =0.56 (1:50 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl3) δ (m, 6H), 7.13 (m, 1H), 6.72 (m, 1H), 5.11 (s, 2H), (m, 1H), (m, 1H), (m, 1H), (d, 3H). 7-Methylbicyclo[4.2.0]octa-1,3,5-trien-5-ol (28d-1). To a stirred solution of 5-benzyloxy-7-methyl- bicyclo[4.2.0]octa-1,3,5-triene (27d, 3.0 g, mmol) in 20 ml of methanol was added Pd/C (0.28 g, 10wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:30 ethyl acetate/hexanes). The title compound was obtained as colorless oil (1.3g) in 95% yield. R f =0.31 (1:30 ethyl acetate/hexanes, TLC). 1 H NMR (400 MHz, CDCl 3 ): δ 7.00 (t, J = 7.8 Hz, 1H), (m, 2H), 4.98 (s, 1H), (m, 1H), (m, 1H),2.59 (d, J = 14.3 Hz, 1H), 1.36 (d, J = 6.6 Hz, 3H). 4-Bromo-7-methyl-bicyclo[4.2.0]octa-1,3,5-trien-5-ol (Compound 6). To a stirred solution of 7-methylbicyclo[4.2.0]octa-1,3,5-trien-5-ol (28d-1, 1.6 g, 11.94mmol) and diisopropylamine(0.12g, 1.19 mmol) in 20 ml of dichloromethane was added N-bromosuccinimide (2.12g, mmol) at 0. Subsequent to the addition, the reaction mixture was stirred for 0.5 hr. The reaction mixture was quenched with sulfuric acid(0.2 M, 20 ml), washed with H 2 O(50 ml 2), and brine (50 ml 2). The organic layer was dried with sodium sulfate. The solvent was removed under reduced pressure. The title compound was obtained as a 12 / 40

13 white solid (1.6 g) in 63% yield. clogp compd6 = Mp: ; R f =0.63 (40:1 hexanes/ethyl acetate, TLC) MS m/z (ESI): Calcd for C 9 H 10 BrO [M + H] Found: H NMR (400 MHz, CDCl3): δ (m, 1H), (m, 1H), 5.44 (s, 1H), (m, 1H), (m, 1H), 2.60 (d, J = 13.9 Hz, 1H), (m, 3H). Synthesis of compound 7: 4-Isopropyl-7-methyl-bicyclo[4.2.0]octa-1,3,5-triene-5,7-diol (Compound 7). To a stirred solution of 5-hydroxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (compound 5, 0.27 g, 1.40 mmol) in 10 ml of dry THF was added dropwise methylmagnesium bromide (3.0 M, 4.66 ml, mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 10 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (10 ml), extracted with ethyl acetate (10 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (15:1 hexanes/ethyl acetate). The title compound was obtained as a yellow solid (130 mg) in 48% yield. clogp compd7 = R f =0.19 (15:1 hexanes/ethyl acetate, TLC) MS m/z (ESI): Calcd for C 12 H 15 O 2 [M H] Found: H NMR (400 MHz, DMSO-d 6 ) δ 8.95 (s, 1H), 6.99 (d, J = 7.3 Hz, 1H), 6.56 (d, J = 7.3 Hz, 1H), 5.39 (s, 1H), 3.19 (hept, J = 6.9 Hz, 1H), (m, 2H), 1.57 (s, 3H), 1.13 (d, J = 6.9 Hz, 3H), 1.12(d, J = 6.9 Hz, 3H). 13 C NMR (100 MHz, DMSO-d 6 ) δ147.4, 139.2, 135.9, 133.5, 126.7, 115.1, 76.5, 46.6, 26.8,26.7, 23.5, Synthesis of compound 8: 2-(Benzyloxy)-3-isopropyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28e). To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a, 13 / 40

14 0.56 g, 2.0 mmol) in 30 ml of methanol was added in p-toluenesulfonic acid (0.53 g, 3.0 mmol). The resulting solution was refluxed at 70 for 6 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (50 ml), extracted with ethyl acetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as colorless oil (370 mg) in 62% yield. R f =0.61 (50:1 hexanes/ethyl acetate, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ 7.46 (d, J = 7.2 Hz, 2H), (m, 2H), (m, 1H), 7.19 (d, J = 7.4 Hz, 1H), 6.74 (d, J = 7.4 Hz, 1H), 5.25 (d, J = 11.8 Hz, 1H), 5.18 (d, J = 11.8 Hz, 1H), 3.46 (d, J = 14.2 Hz, 1H), 3.38 (hept, J = 6.9 Hz, 1H), 3.31(s, 3H), 2.95 (d, J = 14.2 Hz, 1H), 1.75 (s, 3H), 1.22 (d, J = 6.9 Hz, 3H), 1.20 (d, J = 6.9 Hz, 3H). 4-Isopropyl-7-methoxy-7-methyl-bicyclo[4.2.0]octa-1,3,5-trien-5-ol (Compound 8). To a stirred solution of 2-(benzyloxy)-3-isopropyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28e, 2.0 g, 7.03 mmol) in 100 ml of methanol was added Pd/C (0.37 g, 10wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with dichloromethane (80 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:20 ethyl acetate/hexanes). The title compound was obtained as a white solid (0.6 g) in 41.1% yield. clogp compd8 =3.024 Mp: R f =0.20 (20:1 hexanes/ethyl acetate, TLC) MS m/z (ESI): Calcd for C 13 H 17 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ): δ 7.14 (d, J = 7.4 Hz, 1H), 6.71 (d, J = 7.4 Hz, 1H), 5.14 (s, 1H), 3.36 (d, J = 14.0 Hz, 1H), 3.33 (s, 3H), 3.23 (hept, J = 6.9 Hz, 1H), 2.95 (d, J = 14.0 Hz, 1H), 1.70 (s, 3H), 1.25 (d, J = 6.9 Hz, 3H), 1.23 (d, J = 6.9 Hz, 3H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 82.68, 52.17, 40.68, 26.82, 24.24, 23.03, Synthesis of compound 9: 2-(Benzyloxy)-8-ethoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28f). To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a, 1.13 g, 4.0 mmol) in 30 ml of ethanol was added in p-toluenesulfonic acid (0.53 g, 3.0 mmol). The resulting solution was refluxed for 4 h. The reaction mixture was quenched with a saturated 14 / 40

15 solution of sodium bicarbonate (50 ml), extracted with dichloromethane (80 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (50:1 hexanes/ethyl acetate). The title compound was obtained as yellow oil (1.45 g) in 93.5% yield. R f =0.55 (50:1 hexanes/ethyl acetate, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ (m, 2H), (m, 2H), (m, 1H), 7.18 (d, J = 7.4 Hz, 1H), 6.73 (d, J = 7.2 Hz, 1H), 5.27 (d, J = 11.8 Hz, 1H), 5.19 (d, J = 11.8 Hz, 1H), (m, 1H), (m 2H), 3.37 (hept, J = 7.0 Hz,1H), 2.97 (d, J = 14.1 Hz, 1H), 1.75 (s, 3H), (m, 9H). 8-Ethoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 9). To a stirred solution of 2-(benzyloxy)-8-ethoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28f, 1.14 g, 3.67 mmol) and potassium carbonate (0.51 g, 3.67 mmol) in 60 ml of methanol was added Pd/C (0.11 g, 10wt%). The reaction mixture was stirred under a hydrogen atmosphere at room temperature for 1.5 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with dichloromethane (80 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:15 ethyl acetate/hexanes). The title compound was obtained as yellow solid (0.44 g) in 54% yield. clogp compd9 = Mp: R f =0.25 (15:1 hexanes/ethyl acetate, TLC) MS m/z (ESI): Calcd for C 14 H 19 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ) δ 7.15 (d, J = 7.4 Hz, 1H), 6.71 (d, J = 7.4 Hz, 1H), 5.70 (s, 1H), (dq, J = 9.1, 7.0 Hz,1H), (dq, J = 9.1, 7.0 Hz, 1H), 3.34 (d, J = 14.0 Hz, 1H), 3.23 (hept, J = 6.9 Hz, 1H), 2.98 (d, J = 14.0 Hz, 1H), 1.71 (s, 3H), (m, 9H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 81.81, 60.09, 41.65, 26.82, 24.55, 22.96, 22.94, Synthesis of compound 10: 2-(Benzyloxy)-8-isopropoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28g) To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a, 0.55 g, 2.0 mmol) in 30 ml of isopropanol was added in p-toluenesulfonic acid (0.53 g, 3.0 mmol). The resulting solution was refluxed overnight for 3 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (50 ml), extracted with dichloromethane (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was 15 / 40

16 purified by flash column chromatography (40:1 hexanes/ethyl acetate). The title compound was obtained as a colorless oil (0.47 g) in 74% yield. R f =0.56 (40:1 hexanes/ethyl acetate, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ 7.46 (d, J = 7.1 Hz, 2H), (m, 2H), (m, 1H), 7.18 (d, J = 7.4 Hz, 1H), 6.73 (d, J = 7.4 Hz, 1H), 5.49 (d, J = 11.5 Hz, 1H), 5.11 (d, J = 11.5 Hz, 1H), 3.76 (hept, J = 6.2 Hz, 1H), (m, 2H), 3.06 (d, J = 14.0 Hz,1H), 1.74 (s, 3H), (m, 9H), 1.12 (d, J = 6.1 Hz, 3H). 8-Isopropoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 10). To a stirred solution of 2-(benzyloxy)-8-isopropoxy-3-isopropyl-8-methylbicyclo[4.2.0]octa-1,3,5- triene(28g, 0.39 g, 1.21 mmol) and potassium carbonate(0.17 g, 1.21 mmol) in 30 ml of ethyl acetate was added Pd/C (0.04 g, 10wt%). The reaction mixture was stirred under a hydrogen atmosphere at room temperature for 2 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with ethyl acetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:30 ethyl acetate/hexanes). The title compound was obtained as yellow oil (0.21 g) in 75% yield. clogp compd10 = R f =0.21 (30:1 hexanes/ethyl acetate, TLC) MS m/z (ESI): Calcd for C 15 H 21 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ) δ 7.14 (d, J = 7.4 Hz, 1H), 6.70 (d, J = 7.4 Hz, 1H), 5.28 (s, 1H), 3.77 (hept, J = 6.2 Hz,1H), 3.28 (d, J = 14.0 Hz, 1H), 3.21 (hept, J = 6.9 Hz, 1H), 3.01 (d, J = 14.0 Hz, 1H), 1.68 (s, 3H), (m, 6H), 1.19 (d, J = 6.2 Hz,3H), 1.13 (d, J = 6.2 Hz,3H). Synthesis of compound 11: 2-(Benzyloxy)-3-isopropyl-8-(2-methoxyethoxy)-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28h). To a stirred solution of 6-(benzyloxy)-5-isopropyl-1-methyl-1,2-dihydrocyclobutabenzen-1-ol (27a, 0.56 g, 2.0 mmol) in 30 ml of 2-Methoxyethanol was added in p-toluenesulfonic acid (0.53 g, 3.0 mmol). The resulting solution was refluxed for 3 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (50 ml), extracted with ethyl acetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (40:1 hexanes/ethyl acetate). The title compound was obtained as brown oil (0.53 g) in 78% yield. R f =0.46 (40:1 hexanes/ethyl acetate, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ (m, 2H), (m, 2H), (m, 1H), / 40

17 (d, J = 7.3 Hz, 1H), 6.73 (d, J = 7.3 Hz, 1H), 5.33 (d, J = 11.7 Hz, 1H), 5.17 (d, J = 11.7 Hz, 1H), (m, 1H), (m, 3H), 3.47 (d, J = 14.3 Hz, 1H), (m, 1H), 3.32 (s, 3H), 2.99 (d, J = 14.3 Hz, 1H), 1.79 (s, 3H), 1.20 (app t, J = 6.7 Hz, 6H). 3-Isopropyl-8-(2-methoxyethoxy)-8-methylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 11). To a stirred solution of 2-(benzyloxy)-3-isopropyl-8-(2-methoxyethoxy)-8-methylbicyclo[4.2.0] octa-1,3,5-triene (28h, 0.53 g, 1.56 mmol) and potassium carbonate(0.6 g, 4.34 mmol) in 30 ml of ethyl acetate was added Pd/C (0.57 g, 10wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with ethyl acetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:100 ethyl acetate/hexanes). The title compound was obtained as yellow oil (0.25 g) in 65% yield. clogp compd11 = R f =0.22 (1:100 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 15 H 21 O 3 [M H] Found: H NMR (400 MHz, CDCl 3 ) δ 7.28 (s, 1H), 7.15 (d, J = 7.4 Hz, 1H), 6.69 (d, J = 7.4 Hz, 1H), (m, 3H), (m, 1H), 3.45 (s, 3H), 3.30 (hept, J = 6.9 Hz,1H), 3.22 (d, J = 13.6 Hz, 1H), 2.99 (d, J = 13.6 Hz,1H), 1.68 (s, 3H), (d, J = 6.9 Hz, 3H), 1,225 (d, J = 6.9 Hz, 3H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 83.03, 73.27, 64.54, 58.96, 43.12, 26.75, 25.31, 23.01, Synthesis of compound 12: 2-(Benzyloxy)-8-ethyl-3-isopropyl-8-methoxybicyclo[4.2.0]octa-1,3,5-triene (28i). To a stirred solution of 5-benzyloxy-7-ethyl-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27b, 1.48 g, 5.0 mmol) in 45 ml of methanol was added in p-toluenesulfonic acid (1.33 g, 7.5 mmol). The resulting solution was refluxed for 3 h. The reaction mixture was allowed to cool to room temperature, quenched with a saturated solution of sodium bicarbonate (50 ml), extracted with ethylacetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (100:1 hexanes/ethyl acetate, R f =0.64 (TLC)). The title compound was obtained as a brown oil (1.55 g) in 100% yield. 8-Ethyl-3-isopropyl-8-methoxybicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 12). To a stirred solution of 2-(benzyloxy)-8-ethyl-3-isopropyl-8-methoxybicyclo[4.2.0]octa-1,3,5-triene (28i, 1.45 g, 4.67 mmol) and potassium carbonate (0.65 g, 4.67 mmol) in 50 ml of ethyl acetate was added 17 / 40

18 Pd/C (0.15 g, 10wt%). The mixture was stirred under a hydrogen atmosphere at room temperature for 3 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with ethyl acetate (60 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:60 ethyl acetate/hexanes). The title compound was obtained as a yellow solid (0.42 g) in 41% yield. clogp compd12 = Mp: R f =0.23 (1:60 ethyl acetate/hexanes, TLC). MS m/z (ESI): Calcd for C 14 H 19 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ) δ 7.14 (d, J = 7.4 Hz, 1H), 6.71 (d, J = 7.4 Hz, 1H), 5.34 (s, 1H), 3.32 (s, 3H), 3.27 (d, J = 14.1 Hz, 1H), (m, 1H), 2.95 (d, J = 14.1 Hz, 1H), 1.99 (q, J = 7.3 Hz, 2H), (d, J = 6.9 Hz, 3H), 1,233 (d, J = 6.9 Hz, 3H), (t, J = 7.4 Hz, 3H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 86.19, 52.10, 38.52, 30.66, 26.86, 22.97, 22.90, Synthesis of compound 13: 2-Bromo-6-sec-butylphenol (23d). To a stirred solution of 2-sec-butylphenol (22d, 30.0g, mmol) and diisopropylamine (2.02g, 19.9 mmol) in 300 ml of dichloromethane was added N-bromosuccinimide (35.4 g,198.9 mmol) at 0. Subsequent to the addition, the reaction mixture was stirred for 2 h. The reaction mixture was quenched with sulfuric acid (0.2 M, 20 ml), washed with H 2 O (50 ml 2), and brine (50 ml 2). The organic layer was dried with sodium sulfate. The solvent was removed under reduced pressure. The title compound was obtained as yellow oil (41 g) in 89.6% yield. 1 H NMR (400 MHz, CDCl 3 ): δ 7.29 (dd, J = 8.0, 1.5 Hz, 1H), 7.09 (dd, J = 7.7, 1.5 Hz, 1H), (t, J = 7.8 Hz, 1H), 5.55 (s, 1H), (m, 1H), (m, 2H), 1.22 (d J = 7.0 Hz, 3H), 0.86 (t, J = 7.4 Hz, 3H). 2-(Benzyloxy)-1-bromo-3-sec-butylbenzene (24d). To a stirred solution of 2-bromo-6-secbutylphenol (23d, 40.0g, mmol) and potassium carbonate(48 g, 347 mmol) in 250 ml of acetonitrile was added benzyl bromide (30.0 g,175.0 mmol). Subsequent to the addition, the reaction mixture was refluxed for 2 h. The resulting solution was quenched with Et 2 O (100 ml) 18 / 40

19 and filtered. The filtrate was removed under reduced pressure and the title compound was obtained as colorless oil (52.0g) in 93.3% yield. 1 H NMR (400 MHz, CDCl 3 ): δ (m, 2H), (m, 4H), 7.17 (dd, J = 7.8, 1.6 Hz, 1H), 7.00 (t, J = 7.8 Hz, 1H), 4.94 (d, J = 2.7 Hz, 2H), (m, 1H), (m, 2H), (m, 3H), (m, 3H). 5-Benzyloxy-4-sec-butyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26d). To a stirred solution of 2-(benzyloxy)-1-bromo-3-sec-butylbenzene (24d, 25.0g, mmol) and sodium amide (6.04 g, mmol) in 200 ml of THF was added 1,1-diethoxyethene(1e, g, mmol) under nitrogen. Subsequent to the addition, the reaction mixture was refluxed for 15 h. The reaction mixture was poured into ice-water, acidified with con.c HCl(30 ml), extracted with ethyl acetate (200 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:50 ethyl acetate/hexanes). The title compound was obtained as yellow oil (6.21 g) in 28.3% yield. R f =0.31 (1:50 ethyl acetate/hexanes, TLC) 1 H NMR (400 MHz, CDCl 3 ): δ 7.46 (d, J = 7.0 Hz, 2H), (m, 4H), 7.02 (d, J = 7.3 Hz, 1H), 5.51 (s, 2H),3.88 (s, 2H), (m, 1H), (m, 2H), 1.18 (d, J = 7.0 Hz, 3H), (t, J = 7.4 Hz, 3H). 5-Benzyloxy-7-methyl-4-sec-butyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27e). To a stirred solution of 5-benzyloxy-4-sec-butyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26d, 2.0 g, 7.13 mmol) in 50 ml of dry THF was added dropwise methylmagnesium bromide (1.0 M, 8.6 ml, 8.6 mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (30 ml), extracted with ethyl acetate(50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate, R f =0.25 (TLC)). The title compound was obtained as a yellow oil (1.60 g) in 75.7% yield. 2-(Benzyloxy)-3-(sec-butyl)-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28j). To a stirred solution of 5-benzyloxy-7-methyl-4-sec-butyl-bicyclo[4.2.0]octa-1,3,5-trien-7-ol (27e, 1.17 g, 4.0 mmol) in 36 ml of methanol was added in p-toluenesulfonic acid (1.06 g, 6.0 mmol). The resulting solution was refluxed for 3 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (10 ml), extracted with ethyl acetate (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate). The title compound was obtained as yellow oil (1.0 g) in 80.6% yield. R f =0.57 (1:20 ethyl acetate/hexanes, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ (m, 2H), (m, 2H), (m, 1H), 7.14 (app dd, J = 7.4, 2.6 Hz, 1H), 6.74 (app dd, J = 7.4, 2.6 Hz, 1H), 5.23 (app dd, J = 11.8, 2.2 Hz, 1H), 5.16 (app dd, J = 11.8, 2.2 Hz, 1H), 3.45 (d, J = 14.1 Hz, 1H), 3.31 (s, 3H), (m, 19 / 40

20 1H), 2.95 (d, J = 14.1 Hz, 1H), 1.75 (s, 3H), (m, 2H), 1.19 (app dd, J = 7.0, 4.2 Hz, 3H), (app dt, J = 10.7, 7.4 Hz, 3H). 3-(sec-Butyl)-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 13). To a stirred solution of 2-(benzyloxy)-3-(sec-butyl)-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5- triene (28j, 1.0 g, 3.23 mmol) and potassium carbonate(0.45 g, 3.23 mmol) in 100 ml of methanol was added Pd/C (0.1 g, 10wt%). The reaction mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with dichloromethane (80 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:40 ethyl acetate/petroleum ether). The title compound was obtained as yellow oil (0.28 g) in 39.4% yield. clogp compd13 = R f =0.18 (1:40 ethyl acetate/petroleum ether, TLC) MS m/z (ESI): Calcd for C 14 H 19 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ): δ 7.10 (app dd, J = 7.4, 2.1 Hz, 1H), 6.71 (app dd, J = 7.4, 2.3 Hz,1H), 5.38 (s, 1H), 3.36 (d, J = 14.0 Hz, 1H), 3.32 (s, 3H), (m, 2H), 1.70 (s, 3H), (m, 2H), 1.22 (app dd, J = 7.0, 1.6 Hz, 3H), 0.86 (app td, J = 7.4, 5.0 Hz, 3H). Synthesis of compound 14: 2-Bromo-6-ethyl-phenol (23b). To a stirred solution of 2-ethylphenol (22b, 26.8 g, 220 mmol) and diisopropylamine (2.23g, 22.0 mmol) in 130 ml of dichloromethane was added N-bromosuccinimide (40.0 g,220 mmol) at -40. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 2 h. The reaction mixture was quenched with H 2 O(100 ml), extracted with dichloromethane (150 ml 3) and dried with sodium sulfate. The solvent was removed under reduced pressure. The title compound was obtained as a yellow oil (32.5 g) in 73% yield. 2-Benzyloxy-1-bromo-3-ethyl-benzene (24b). To a stirred solution of 2-bromo-6-ethyl- phenol (23b, 32.5 g, mmol) and potassium carbonate (30.6 g, 220mmol) in 200 ml of acetonitrilewas added benzyl bromide (44.16 g,320.0 mmol). Subsequent to the addition, the reaction mixture was refluxed overnight. The resulting solution was filtered. The filtrate was 20 / 40

21 removed under reduced pressure and the title compound was obtained as a yellow oil (42.0g) in 90.5 % yield. 5-Benzyloxy-4-ethyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26b). To a stirred solution of 2-benzyloxy-1-bromo-3-ethyl-benzene (24b, 10.0g, mmol) and sodium amide (6.1 g, mmol) in 50 ml of THF was added 1,1-diethoxyethene(25, 12.1 g, mmol) under nitrogen. Subsequent to the addition, the reaction stirred at 60 overnight. The reaction mixture was poured into ice-water, acidified with conc. HCl (30 ml), extracted with ethyl acetate (50 ml 3), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (1:100 ethyl acetate/hexanes, R f =0.55 (TLC)). The title compound was obtained as brown oil (3.4 g) in 39.1% yield. 5-(Benzyloxy)-4-ethyl-7-methylbicyclo[4.2.0]octa-1,3,5-trien-7-ol (27f). To a stirred solution of 5-benzyloxy-4-ethyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26b, 2.32 g, 9.2 mmol) in 50 ml of dry THF was added dropwise methylmagnesium bromide (3.0 M, 4.3 ml, 12.9 mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 1 hr. The reaction mixture was quenched with a saturated solution of ammonium chloride (30 ml), extracted with ethyl acetate(50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate, R f =0.25 (TLC)). The title compound was obtained as a yellow oil (1.78 g) in 72.3% yield. 2-(Benzyloxy)-3-ethyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28k). To a stirred solution of 5-(benzyloxy)-4-ethyl-7-methylbicyclo[4.2.0]octa-1,3,5-trien-7-ol (27f, 1.78 g, 6.64 mmol) in 60 ml of methanol was added in p-toluenesulfonic acid (1.77 g, 9.96 mmol). The resulting solution was refluxed for 3 h. The reaction mixture was quenched with a saturated solution of sodium bicarbonate (10 ml), extracted with ethyl acetate (50 ml 2), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (20:1 hexanes/ethyl acetate). The title compound was obtained as yellow oil (1.86 g) in 99.5% yield. R f =0.55 (1:20 ethyl acetate/hexanes, TLC) 1 H NMR (400 MHz, CDCl 3 ) δ (m, 2H), (m, 2H), (m, 1H), 7.13 (d, J = 7.2 Hz, 1H), 6.71 (d, J = 7.2 Hz, 1H), 5.24 (d, J = 11.8 Hz, 1H), 5.17 (d, J = 11.8 Hz, 1H), 3.46 (d, J = 14.2 Hz, 1H), 3.30 (s, 3H), 2.95 (d, J = 14.2 Hz, 1H), 2.67 (q, J = 7.6 Hz, 2H), 1.75 (s, 3H), 1.19 (t, J = 7.6 Hz, 3H). 3-Ethyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-trien-2-ol (Compound 14). To a stirred solution of 2-(benzyloxy)-3-ethyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (28k, 1.86 g, 6.59 mmol) and potassium carbonate (0.126 g, 0.91 mmol) in 20 ml of methanol was added Pd/C (0.19 g, 10wt%). The reaction mixture was stirred under a hydrogen atmosphere at room temperature for 4 h. The resulting solution was filtered. The filtrate was acidified with HCl (3M), extracted with dichloromethane (80 ml 2), and dried with sodium sulfate. The solvent was 21 / 40

22 removed under reduced pressure. The residue was purified by flash column chromatography (1:20 ethyl acetate/hexanes). The title compound was obtained as a white solid (0.97 g) in 77% yield. clogp compd14 = Mp: R f =0.25 (1:20 ethyl acetate/hexanes, TLC) MS m/z (ESI): Calcd for C 12 H 15 O 2 [M H] Found: H NMR (400 MHz, CDCl 3 ): δ 7.09 (d, J = 7.2 Hz, 1H), 6.69 (d, J = 7.2 Hz, 1H), (br, 1H), 3.38 (d, J = 14.0 Hz, 1H), 3.34 (s, 3H), 2.95 (d, J = 14.0 Hz, 1H), 2.62 (q, J = 7.6 Hz, 2H), 1.70 (s, 3H), 1.22 (t, J = 7.6 Hz, 3H). 13 C NMR (101 MHz, CDCl 3 ) δ , , , , , , 82.42, 52.13, 40.75, 24.17, 23.17, Synthesis of compound 15: 5-(Benzyloxy)-2-bromo-4-isopropylbicyclo[4.2.0]octa-1,3,5-trien-7-one (29). To a stirred suspension of 5-benzyloxy-4-isopropyl-bicyclo[4.2.0]octa-1,3,5-trien-7-one (26a, 1.00 g, 3.76 mmol) and zinc chloride(12.8 g, 9.39 mmol) in 50 ml of acetic acid was added benzyl trimethyl ammonium tribromide (6.59 g, mmol) under nitrogen. Subsequent to the addition, the reaction mixture was stirred for 5 h. The reaction mixture was quenched with a solution of sodium thiosulfate (10%, 40 ml), extracted with dichloromethane (40 ml 3), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (10:1 hexanes/ethyl acetate). The title compound was obtained as a yellow solid (1.02 g) in 78% yield. R f =0.40 (1:10 ethyl acetate/hexanes, TLC) 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.57 (s, 1H), (m, 5H), 5.44 (s, 2H), 3.93 (s, 2H), 3.22 (hept, J = 6.9 Hz, 1H), 1.15 (d, J = 6.9 Hz, 6H). 5-(Benzyloxy)-2-bromo-4-isopropyl-7-methylbicyclo[4.2.0]octa-1,3,5-trien-7-ol (30). To a stirred solution of 5-(benzyloxy)-2-bromo-4-isopropylbicyclo[4.2.0]octa-1,3,5-trien-7-one (29, 1.01 g, 2.93 mmol) in 30 ml of toluene was added dropwise methylmagnesium bromide (3.0 M, 1.46 ml, 4.39 mmol) under nitrogen at 78. Subsequent to the addition, the reaction mixture was allowed to warm to room temperature and stirred for 3 h. The reaction mixture was quenched with a saturated solution of ammonium chloride (10 ml), extracted with dichloromethane (10 ml 3), and dried with sodium sulfate. The solvent was removed under reduced pressure. The residue was purified by flash column chromatography (10:1 hexanes/ethyl acetate, R f = 0.18 (TLC)). The title compound was obtained as a yellow solid (0.95 g) in 90% yield. 2-(Benzyloxy)-5-bromo-3-isopropyl-8-methoxy-8-methylbicyclo[4.2.0]octa-1,3,5-triene (31). 22 / 40