Experimental section

Procedure #1: Imine deprotonation: A solution of N-benzylidenehex-5-en-1-amine (1) (357 mg, 1.90 mmol) in THF (4 ml) was added in a dropwise fashion to a cold (-78 ^oC) solution of lithium diisopropylamine (LDA, 3.42 mmol, from butyllithium and diisopropylamine) in THF (34 ml). After warming to room temp. for 18 h, the black solution was diluted with water and extracted twice with diethyl ether. The organic phases were combined, washed with saturated aqueous sodium chloride, dried (MgSO₄), and concentrated to give an orange residue. Flash chromatography (2-10% MeOH CHCl₃ gradient elution) gave 282 mg (79%) of a 4.1:1 mixture of 4a and 4b.
On mixture of 4a and 4b: IR (neat) 3336 (w), 2948 (s), 2859 (m), 1948 (w), 1881 (w), 1808 (w), 1493 (w), 1448 (m), 699 (s) cm-1; Anal. Calc. for C₁₃H₁₇N: C, 83.36; H, 9.15; N, 7.48. Found: C, 83.32; H, 9.26; N, 7.28.
Major isomer 4a: ¹H NMR (360 MHz, CDCl₃) delta 7.4-7.2 (m, 5H), 4.24 (t, 1H, J 7.5 Hz), 3.9 (m, 1H), 2.67 (m, 1H), 2.4 (bs, 1H), 1.9-1.4 (m, 8H); Carbon 13 NMR (75 MHz, CDCl₃) delta 144.1, 129.3, 126.9, 126.7, 126.5, 63.5, 61.3, 42.8, 42.5, 36.2, 33.7, 15.9. MS (EI, m/z) 187 (50), 186 (54), 158 (90), 144 (89), 132 (48), 110 (100), 104 (78), 91 (50), 77 (39).

Minor isomer 4b: ¹H NMR (360 MHz, CDCl₃) delta 3.99 (dd, 1H, J 5.3, 10.9 Hz), 3.74 (t, 1H, J 7.7 Hz), 2.6 (m, 1H), 2.3 (ddd, 1H, J 5.5, 9, 12 Hz), 1.27 (m, 1H); Carbon 13 NMR (75 MHz, CDCl₃) delta 128.7, 127.0, 126.7, 63.8, 63.4, 43.1, 43.9, 34.6, 33.1, 23.8. MS (EI, m/z) 187 (80), 186 (83), 158 (100), 144 (66), 132 (39), 110 (53), 105 (31), 104 (51), 91 (34), 77 (31), 67 (29), 41 (49), 39 (36); HRMS: calc, 187.1361; found, 187.1356.

Procedure #2: Cycloreversion of Imidazolidine 16: A solution of 0.185 g ( 0.494 mmol) of 16 (see below) in 5.0 ml of dry THF was cooled to -70 °C and treated with 0.65 ml (1.0 mmol) of a 1.6 M solution of LDA in cyclohexane. The solution became orange-coloured and was allowed to warm slowly to room temp.. After 72 h, water was added, and the mixture was extracted with ether. The organic layer was washed with brine, dried (MgSO₄), and concentrated to give 0.142 g (77% crude yield) of a deep-red liquid. ¹H NMR showed this to be a mixture of 4 contaminated with imidazolidines 10 and 11 and vinylic-hydrogen-containing side-products. There was no starting material. The bicyclic pyrrolidines could be separated by gradient chromatography (5-100% ethyl acetate/ hexane) on silica gel, producing 18.8 mg (21% yield) of a 1:1.87 mixture of 4a and 4b.

Procedure #3: Imidazolidine Cycloreversion: n-Butyllithium (0.280 ml of a 1.56 M solution in hexane, 0.437 mmol) was added in a dropwise fashion to a cold (-78 C) solution of the imidazolidine 20 (116 mg, 0.347 mmol, see below for preparation) in THF (35 ml). After 10 min, the solution was warmed to room temp. for 5 h. The dark solution was diluted with water and extracted with diethyl ether. The organic layer was washed with brine, dried (MgSO₄), and concentrated. Chromatography as above gave 31.7 mg (49%) of a 1:10 mixture of 4a and 4b.

2,3a-Diphenyloctahydro-(2R*,3aS*,6aR*)-cyclopenta[b]pyrrole (22a) and 2,3a-Diphenyloctahydro-(2S*,3aS*,6aR*)-cyclopenta[b]pyrrole (22b).

Procedure #1: Imine Deprotonation: A solution of N-benzylidene-5-phenylhex-5-en-1-amine (23) (329 mg, 1.25 mmol) in THF (4 ml) was added in a dropwise fashion to a cold (-78 ^oC) solution of lithium diisopropylamine (LDA, 2.1 mmol, from n-butyllithium and diisopropylamine) in THF (25 ml). After warming to room temp. for 20h, the black solution was diluted with water and extracted twice with ether. The organic phases were combined, washed with saturated aqueous sodium chloride, dried (MgSO₄), and concentrated to give an orange residue. Flash chromatography (5-100% EtOAc-hexane gradient elution) gave 14.9 mg (4.6%) of 2,3a-diphenylhexahydrocyclopenta[b]pyrrole (not shown) and 176 mg (54%) of a 6:1 mixture of 22a and 22b.

Major isomer 22a: IR (neat) 3336 (w), 1949 (w), 1880 (w), 1806 (w), 1737 (w), 1603 (m), 1494 (m), 1446 (m), 751 (s) cm-1; ¹H NMR (300 MHz, CDCl₃) delta 7.3 (bm, 10H), 4.45 (dd, 1H, J 5.5, 11.0 Hz), 4.15 (dd, 1H, J 4, 8 Hz), 2.47 (dd, 1H, J 7, 12 Hz), 2.4-1.6 (bm, 7H); Carbon 13 NMR (75 MHz, CDCl₃) delta 150.3 (s), 143.6 (s), 128.4, 127.0, 126.7, 126.0, 125.5, 69.9 (d), 61.9 (d), 58.7 (s), 51.9 (t), 41.6 (t), 37.3 (t), 25.9 (t). MS (EI, m/z,%) 263 (65, M+), 262 (23), 220 (17), 186 (6), 158 (100), 130 (40), 115 (23), 106 (46), 91 (32).

Minor isomer 22b: IR (CHCl3) 1949 (w), 1884 (w), 1811 (w), 1600 (w), 1496 (m), 1455 (m) cm-1; ¹H NMR (360 MHz, CDCl₃) delta 7.3 (bm, 10H), 4.23 (dd, 1H, J-5.3, 11.2 Hz), 4.11 (d, 1H, J 5.7 Hz), 2.47 (dd, 1H, J-5.3, 12.6 Hz), 2.1-1.6 (bm, 7H); Carbon 13 NMR (75 MHz, CDCl₃) delta 128.3, 127.1, 126.7, 126.3, 125.7, 69.1, 61.8, 58.8, 50.5, 42.2, 35.3, 24.3; MS (EI, m/z, %) 264 (12), 263 (73, M+), 262 (23), 220 (11), 158 (100), 143 (32), 130 (28), 115 (12), 106 (30).

On the mixture of 22a and 22b: Anal. Calc. for C₁₉H₂₁N: C, 86.69; H, 8.04; N, 5.32. Found: C, 86.45; H, 8.04; N, 5.28.

Procedure #2: Cycloreversion of Imidazolidine 21: n-Butyllithium (0.55 ml of a 1.3 M solution in hexane, 0.71 mmol) was added in a dropwise fashion to a cold (-78 ^oC) solution of the imidazolidine 21 (203 mg, 0.477 mmol, see below for preparation) in THF (47 ml). After 10 min, the solution was warmed to room temp. overnight. The dark solution was diluted with water and extracted with ether. The organic layer was washed with brine, dried (MgSO₄), and concentrated. Chromatography as above gave 66.5 mg (53%) of an 1:11 mixture of 22a and 22b. A trace of 2,3a-diphenylhexahydrocyclopenta[b]pyrrole (not shown) was also isolated.

2,4-Diphenyl-3-hexyl-5-pentylimidazolidine (10) and 4,5-Diphenyl-3-hexyl-2-pentylimidazolidine (11).

A roundbottomed flask was charged with 4.54 g (0.024 mol) of the imine 9 and 125 ml of dry THF and cooled to 2-3 ^oC. This cold solution was treated with 9.0 ml of a 1.6 M solution of LDA in cyclohexane and allowed to stir on the ice-bath. The reaction mixture slowly became orange and then gradually became a dark black. After stirring for five h, the dark solution was quenched with water, this addition causing the reaction mixture to change to a light-yellow colour. The mixture was diluted with water and extracted with diethyl ether. The organic phase was washed with brine, dried (MgSO₄), and concentrated to give 3.77 g (83% crude yield) of a 4.8:1.0 mixture of 10 and 11 as a yellowish oil, as determined by ¹H NMR. When a similar reaction was run using benzene as solvent, a 1:4.3 mixture of 10 and 11 was obtained.

Data for 10, obtained on the 4.8:1 mixture from the THF reaction: IR (film): 3342 (vw), 3064 (w), 3030 (w), 2957 (vs), 2931 (vs), 2858 (s), 1948(vw), 1882 (vw), 1809 (vw), 1603 (w), 1490 (m), 1457 (m), 1164 (m), 753 (s), 700 (vs) cm-1. ¹H NMR (300 MHz, CDCl₃): delta 7.64 (m, 2H), 7.52 (m, 2H), 7.45-7.15 (m, 6H), 4.51 (s, 1H), 3.40 (d, 1H, J 7.2 Hz), 3.15 (m, 1H), 2.41 (dist. t, 2H), 2.15 (1H, N-H), 1.5-0.7 (bm, 22H). 1H decoupling: Irradiation at delta 3.40 caused the multiplet at 3.15 to collapse. 13C NMR (75 MHz, CDCl₃): delta 143.5, 143.1, 128.4, 128.2, 128.1, 127.7, 127.6, 127.1, 82.6, 75.8, 66.3, 52.4, 34.6, 32.0, 31.4, 27.7, 27.0, 26.8, 22.6, 22.4, 14.0, 13.9. MS, m/z (%): 378(0.3, M+), 377(1.1), 301(4), 279(3), 208(0.8), 202(2), 194(4), 190(100), 174(l.4), 118(5), 91(9).

Data for 11, obtained on the 1:4.3 mixture from the benzene reaction: ¹H NMR (300 MHz, CDCl₃): delta 7.3-7.15 (m, 10H), 4.12(d, 1H, J 7.6 Hz), 3.87 (dd, 1H, J 3.0, 7.1 Hz), 3.57 (d, 1H, J 7.6 Hz), 2.55 (m, 2H), 1.9-0.7 (bm, 22H). 1H decoupling: Irradiation of the doublet at delta 4.12 caused the doublet at delta 3.57 to collapse to a singlet. 13C NMR (75 MHz, CDCl₃): delta 142.4, 128.3, 128.2, 127.8,127.1, 80.6, 78.3, 69.4, 52.5, 36.5, 32.5, 31.6, 28.1, 27.8, 25.1, 22.8, 22.6, 14.1, 14.0. MS, m/z (%): 377(2, M-1), 376(7), 375(3), 320(20), 299(6), 277(6), 250(13), 243(27), 187(50), 186(100), 180(56), 158(21), 144(19), 91(36). Anal. Calc. for C₂₆H₃₈N₂ : C, 82.55; H, 10.04; N, 7.41. Found: C, 82.58; H, 10.01; N, 7.47.

5-Pentyl-2,3,4-triphenylpyrrolidine (12).

A round-bottomed flask was charged with 0.223 g (0.589 mmol) of a 4.8:1 mixture of 10 and 11 (obtained from the above dimerization carried out in THF), 0.217 g (1.2 mmol) of trans-stilbene and 12 ml of dry THF. This solution was cooled to -70 ^oC and then treated with 0.37 ml ( 0.59 mmol) of a 1.6 M solution of LDA in cyclohexane. The solution instantaneously became purple and was allowed to warm to room temp.. After 7 h the still purple solution was quenched with aqueous ammonium chloride and extracted with diethyl ether. The organic layer was washed with brine, dried (MgSO₄), and concentrated to give 0.282 g (62%) of the title compound. ¹H NMR showed this material to be pure, and to be comprised of a mixture of three diastereomers in a ratio of 3.3:2:1 (12a:12b:12c). A mixture of isomers 12a and 12c could be separated from isomer 12b by column chromatography (25% ethyl acetate/hexane, silica gel).

IR (film, mixture of all three diastereomers): 3329 (vw), 3084 (w), 3061 (w), 3028 (w), 2954 (m), 2870 (m), 2855 (m), 1948 (vw), 1875 (vw), 1809 (vw), 1602 (m), 1495 (m), 1465 (m), 1453 (m), 909 (m), 751 (m), 737 (s), 699 (vs) cm-1.

Peaks assigned to isomer 12a: ¹H NMR (300 MHz, CDCl₃): delta 7.4-7.1 (m, 15H), 4.30 (d, 1H, J 9.3 Hz), 3.68 (m, 1H), 3.54 (t, 1H, J 7.8 Hz), 3.30 (dd, 1H, J 7.8, 9.2 Hz), 2.14 (bs, 1H), 1.4-1.0 (m, 8H), 0.80 (t, 3H, J 6.7 Hz). 1H decoupling: Irradiation at delta 4.3 caused the dd at delta 3.30 to collapse to a singlet. Irradiation at delta 3.68 caused the triplet at delta 3.54 to collapse to a doublet. Irradiation at delta 3.54 caused the dd at delta 3.30 to collapsed to a doublet and affected the multiplet at delta 3.68. Irradiation at delta 3.30 caused the doublet at delta 4.30 to collapse to a singlet and the triplet at 3.54 to collapse to a doublet. 13C NMR (75 MHz, CDCl₃): delta 142.6, 142.3, 142.2, 129.2, 128.2, 128.1, 128.0, 127.8, 127.5, 127.3, 127.0, 126.8, 126.2, 126.0, 70.6(d), 62.8(d), 61.8(d), 57.2(d), 33.0, 31.9, 26.8, 22.5, 13.9. Anal. Calc. for C₂₇H₃₁N: C, 87.81; H, 8.39; N, 3.79. Found: C, 87.62; H, 8.68; N, 3.68.

Isomer 12b: ¹H NMR (300 MHz, CDCl₃): delta 7.35-6.9 (m, 15H), 4.49 (d, 1H, J 9.2 Hz), 3.64 (dt, 1H, J 4.0, 8.6 Hz), 3.36 (dd, 1H, J 9.3, 11.2 Hz), 3.12 (dd, 1H, J 8.9, 11.2 Hz), 2.1 (bs, 1H), 1.6-1.1 (m, 8H), 0.84 (m, 1H). 13C (75 MHz, CDCl₃): delta 144.4, 141.1, 140.3, 128.5, 128.3, 128.0, 127.1, 126.7, 126.5, 126.4, 69.1, 66.0, 64.0, 61.5, 35.9, 32.0, 26.9, 22.6, 14.0.

Peaks assigned to isomer 12c: ¹H NMR (300 MHz, CDCl₃, partial): delta 4.83 (d, 1H, J 9.5 Hz).

2-(N-Hexyl)-2-phenyl-l-pentyl-1,2-ethanediamine (14) and 1,2-Diphenyl-2-(N-hexyl)-1,2-ethanediamine (15).

A solution comprised of 11.0 g (0.029 mol) of imidazolidines 10 and 11 (as a 1:2.7 mixture from the benzene dimerization reported above) in 50 ml of THF was cooled to 0 ^oC, treated with 100 ml of 1.5% aqueous hydrochloric acid and allowed to stir for 12 h. Acid-base work-up of this green solution and concentration of the dried organic extracts gave 4.06 g of the title compounds as a yellowish liquid. These two diamines could be conveniently separated by gradient column chromatography (5%-10%-25% ethyl acetate/hexane, grade IV alumina, 35:1 loading.) Compound 14 was obtained as a 4.4:1 mixture of diastereomers. Compound 15 was obtained as a single diastereomer, later determined to be the (R*R*)-diastereomer.

Data for 14 (mixture of diastereomers): IR (film): 3376 (vw), 3309 (vw), 3064 (w), 3024 (w), 2956 (vs), 2926 (vs), 2871 (s), 2856 (vs), 1948 (vw), 1888 (vw), 1815 (vw), 1602 (m), 1465 (m), 1453 (m), 757 (w), 702(s) cm-1. ¹H NMR for major diastereomer (300 MHz, CDCl₃): delta 7.4-7.2 (m, 5H), 3.54 (d, 1H, J 4.7 Hz), 2.91 (m, 1H), 2.43 (t, 2H, J 7.1 Hz), 1.6-1.1(m, 18H), 0.9-0.8 (m, 6H). Partial ¹H NMR data for minor diastereomer: delta 3.26 (d, 1H, J 7.6 Hz), 2.75 (m, 1H). 13C NMR (major diastereomer only, 75 MHz, CDCl₃) delta 141.4, 128.3, 128.0, 127.0, 68.4, 55.9, 47.9, 34.5, 32.0, 31.8, 30.4, 27.1, 26.3, 22.6, 13.9. MS, m/z (%): 291(0.2, M+1), 219(0.4), 191(22), 190(100), 118(11), 106(26), 100(23), 79(6), 43(12).

Data for 15: IR (film): 3382 (vw), 3316 (vw), 3062 (w), 3028 (w), 2954 (s), 2926 (vs), 2869 (m), 2855 (m), 1602 (m), 1492 (m), 1453 (s), 766 (m), 699 (vs), 607 (m) cm-1. ¹H NMR (300 MHz, CDCl₃): delta 7.3-7.1 (m, 10H), 3.98 (d, 1H, J 7.1 Hz), 2.39 (m, 2H), 1.8 (bs, 3H), 1.5-1.0 (m, 10H), 0.84 (t, 8H, J 6.8 Hz). 13C NMR (75 MHz, CDCl₃): delta 143.9, 141.9, 128.0, 127.9, 127.9, 127.1, 126.8, 70.0, 62.0, 47.9, 31.7, 30.2, 26.9, 22.6, 13.9. MS, m/z (%): 225(0.07, M-71), 208(0.13), 191(19), 190(100), 118(9), 106(33), 100(0.13), 91(8), 79(10), 43(12).

4,5-Diphenyl-3-hexyl-2-(4-pentenyl)imidazolidine (16).

A solution of 0.089 g (0.3 mmol) of 15 in 5 ml dry benzene was treated with 0.0386 g (0.39 mmol) of 4-hexenal and heated to reflux through a Dean-Stark trap. After 90 min, the solution was cooled and the solvent was removed in vacuo to give 0.11 g (100% yield) of the title compound: IR (film): 3329 (vw), 3063 (m), 3029 (m), 2953 (vs), 2929 (vs), 2857 (s), 1948 (vw), 1882 (vw), 1822 (vw), 1641 (m), 1602 (m), 1494 (m), 1454 (s), 1376 (m), 1170 (m), 1028 (m), 993 (m), 911 (m), 759 (s), 700 (vs) cm-1. ¹H NMR (300 MHz, CDCl₃): delta 7.3-7.1 (m, 10H), 5.86 (m, 1H, HC=C), 5.05 (m, 2H, H2C=C), 4.11 (d, 1H, J 7.6 Hz), 3.89 (dd, 1H, J 2.9, 6.7 Hz), 3.57 (d, 1H, J 7.7 Hz), 2.55 (m, 2H), 2.17 (m, 2H), 1.9-1.6 (m, 4H), 1.3-1.0 (m, 8H), 0.81(t, 3H, J 6.9 Hz). 13C NMR (75 MHz, CDCl₃): delta 142.2, 138.8, 128.2, 128.1, 127.7, 127.1, 127.0, 114.6, 80.2, 78.2, 69.4, 52.5, 35.8, 34.0, 31.6, 28.0, 27.2, 24.7, 22.6, 14.0. MS, m/z 375(1, M+), 374(7), 373(13), 320(8), 319(7), 298(19), 297(100), 277(8), 243(36), 187(15), 186(26), 185(41), 184(93), 180(89), 170(25), 157(17), 156(35), 131(26), 130(25), 117(23), 104(47), 91(62). Anal. Calc. for C₂₆H₃₆N₂: C, 83.00; H, 9.57; N, 7.14. Found: C, 82.86; H, 9.49; N, 7.14.

A 1L flask was charged with 12.04 g of stilbenediamine (17) [15] (0.0567 mol) and 560 ml of THF which had been dried over Drierite. Dry acetone (3.749 g, 0.0646 mol) was added with stirring, followed by 30 g of 4 Å molecular sieves. After 4h at room temp., the reaction was not complete by NMR, and 2 ml more acetone was added. After stirring overnight, the mixture was filtered through Celite and the filtrate was concentrated to give crude (d,l)-stilbenediamine acetonide (18), which was used immediately. No other products were observed by GC or by NMR. ¹H NMR (360 MHz, CDCl₃) delta 7.35-7.15 (m, 10H), 4.24 (s, 2H), 2.13 (br, 2H), 1.53 (s, 6H).

The crude acetonide (18) from above was dissolved in 60 ml of absolute ethanol and treated with sodium borohydride (3.267 g) in 50 ml of ethanol. After stirring overnight, water and dilute NaOH were added, and most of the ethanol was removed in vacuo. The concentrate was extracted diethyl ether (3 X 100 ml. The combined ethereal layers were washed with brine and dried (Na2SO4), then concentrated. The crude diamine was Kugelrohr distilled (0.8 mm Hg, 125 ^oC air bath) to give 12.86 g of the title compound as a colourless oil (89% from stilbenediamine): IR (neat) 3382 (br), 3309 (br), 2961 (s), 1601, 1492, 1469, 1452 (s), 1379, 767, 700 (s) cm^-1; ¹H NMR (360 MHz, CDCl₃) delta 7.20-7.05 (m, 10H), 3.95 (d, J 7.2 Hz, 1H), 3.78 (d, J 7.2 Hz, 2H), 2.60-2.45 (m, J 6.2 Hz, 1H), 1.8-1.6 (br, 1H), 0.93 (dd, J 6.2 Hz, 6H); 13C NMR (90 MHz, CDCl₃) delta 143.6, 142.2, 127.9, 127.7, 127.6, 127.1, 126.8, 126.7, 67.0, 61.9, 45.8, 24.4, 21.9; MS (CI, isobutane, m/z, %) 255 (100), 148 (59), 106 (50), 256 (20), 238 (16), 149 (10), 196 (6), 104 (6). HRMS calc 255.1861 (M+1), found 255.1862.

(4R*, 5R*)-4,5-Diphenyl-3-(1-methylethyl)-2-(pent-4-enyl)imidazolidine (20).

Hex-5-enal (98 mg, 1.00 mmol) and the diamine 19 (254 mg, 1.00 mmol) in diethyl ether (14 ml) were stirred overnight in the presence of 4Å molecular sieves. The mixture was filtered through Celite and concentrated to give 295 mg (88%) of a pale-yellow oil that was found to be pure by proton NMR; ¹H NMR (360 MHz, CDCl₃) delta 7.4-7.1 (m, 10H), 5.95-5.75 (m, 1H), 5.11-4.95 (m, 2H), 4.18-4.12 (dd, J 3.5, 7.4 Hz, 1H), 4.07 (d, J 7.6 Hz, 1H), 3.90 (d, J 7.6 Hz, 1H), 3.05-2.90 (m, 1H), 2.3-2.1 (m, 2H), 2.0 (br, 1H), 1.9-1.3 (m, 4H), 1.0-0.9 (dd, J 6.5 Hz, 6H); 13C NMR (90 MHz, CDCl₃) delta 143.7, 141.0, 138.9, 128.2, 128.0, 127.4, 127.2, 126.8, 114.5, 75.9, 73.0, 69.6, 49.9, 37.9, 33.9, 25.4, 20.4, 19.6; IR (neat) 3028, 2963, 2929, 1494, 1453, 1384, 1365, 1180, 911, 759, 700. MS (EI, m/z,%) 335(4), 266 (20), 265 (95), 149 (11), 148 (100), 106 (26), 91 (12), 81 (13); HRMS: calc 335.2487; found 335.2502.

(4R*, 5R*)-4,5-Diphenyl-3-(1-methylethyl)-2-(4-phenylpent-4-enyl)imidazolidine (21).

5-Phenyl-hex-5-enal (190 mg, 1.09 mmol) and the diamine 20 (277 mg, 1.09 mmol) in diethyl ether (14 ml) were stirred overnight in the presence of 4Å molecular sieves. The mixture was filtered through Celite and concentrated to give 378 mg (86%) of a pale-yellow oil that was found to be pure by proton NMR; IR (neat) 3030, 2964, 2931, 2864, 1656, 1629, 1603, 1497, 1450, 1178, 1025, 899, 779, 759, 700 cm^-1; ¹H NMR (360 MHz, CDCl₃) delta 7.5-6.9 (m, 15H), 5.3 (s, 1H), 5.13 (s, 1H), 4.15-4.10 (m, 1H), 4.05 (d, J 7.6 Hz, 1H), 3.9 (d, J 7.6 Hz, 1H), 3.05-2.85 (m, 1H), 2.70-2.55 (m, 2H), 2.0 (br, 1H), 1.9-1.6 (m, 4H), 1.1-0.8 (m, 6H); MS (EI, m/z,%) 411 (M+1, 1), 410 (M+, 2), 266 (28), 265 (100), 148 (54), 106 (15), 91 (17); HRMS: calc 410.2722, found 410.2706.