5384
Z. E. Wilson et al. / Tetrahedron 63 (2007) 5379–5385
4.1.3. Procedure for the synthesis of analogue 9.
(1.5 mL) and the mixture heated to reflux for 2 h. The reac-
tion mixture was poured into a separating funnel containing
water (5 mL) and shaken. The aqueous layer was extracted
with dichloromethane (6ꢂ5 mL) and the organic extracts
were combined and washed with saturated sodium bicarbon-
ate solution (10 mL) and brine (10 mL), then dried over
magnesium sulfate. The solvent was removed in vacuo and
the resulting bright yellow oil purified via flash chromato-
graphy using hexane–ethyl acetate (4:1, Rf 0.31) as eluent to
afford the title compound 24 (98 mg, 87%) as a colourless
oil; nmax (film) 3130, 2928, 2850, 1725, 1622, 1587, 1499,
4.1.3.1. 14-(40,60-Dimethoxy-10H-indol-10-yl)tetradec-
1-en-5-yl acetate 22. To a solution of alcohol 12 (45 mg,
0.12 mmol) in pyridine (5 mL) were added acetic anhydride
(0.1 mL, 10 mmol) and N,N-4-dimethylaminopyridine
(10 mg, 0.82 mmol). The reaction mixture was stirred at
room temperature for 5 h, then extracted with diethyl ether
(3ꢂ20 mL), washed with brine (20 mL) and dried over mag-
nesium sulfate. The combined organic extracts were concen-
trated in vacuo and the crude product was purified by flash
chromatography using hexane–ethyl acetate (7:3, Rf 0.64)
as eluent to afford the title compound 22 (45 mg, 90%) as
a yellow oil; nmax (film) 2928, 2854, 1731, 1587, 1500,
1
1465, 1384, 1326, 1283, 1250, 1147, 1096, 971 (C–O); H
NMR (400 MHz; CDCl3) d 1.25–1.34 (12H, m, 30-H, 40-H,
50-H, 60-H, 70-H, 80-H), 1.71–1.81 (4H, m, 90-H, 110-H),
1.83–1.93 (2H, m, 20-H), 2.13–2.17 (2H, m, 120-H), 3.86
(3H, s, OCH3), 3.91 (3H, s, OCH3), 4.00 (2H, t, J¼7.1 Hz,
10-H), 4.97–5.06 (2H, m, 140-H), 5.62–5.63 (1H, m,
100-H), 5.76–5.83 (1H, m, 130-H), 6.22 (1H, d, J¼1.5 Hz,
5-H), 6.40 (1H, d, J¼1.5 Hz, 7-H), 6.48 (1H, d, J¼3.2 Hz,
3-H), 6.87 (1H, d, J¼3.2 Hz, 2-H), 7.03 (1H, d, J¼1.6 Hz,
500-H), 7.63 (1H, d, J¼1.6 Hz, 400-H), 8.34 (1H, s, 200-
1455, 1250, 1210, 1069, 936, 737 cmꢁ1
;
1H NMR
(300 MHz, CDCl3) d 1.22–1.81 (20H, m, 13-H, 12-H, 11-
H, 10-H, 9-H, 8-H, 7-H, 6-H, 4-H, 3-H), 2.03 (3H, s,
OCOCH3), 3.85 (3H, s, OCH3), 3.90 (3H, s, OCH3), 3.99
(2H, t, J¼7.0 Hz, NCH2), 4.10–4.12 (1H, m, 5-H), 4.94–
5.04 (2H, m, CH]CH2), 5.70–5.80 (1H, m, CH]CH2),
6.21 (1H, s, 70-H), 6.39 (1H, s, 50-H), 6.47 (1H, d,
J¼2.7 Hz, 30-H), 6.86 (1H, d, J¼2.7 Hz, 20-H); 13C NMR
(75 MHz, CDCl3) d 21.1 (OCOCH3), 25.1, 26.8, 29.1,
29.3, 29.4, 29.45, 29.5, 30.0 (CH2, C-13, C-12, C-11, C-
10, C-9, C-8, C-7, C-3), 33.2 (CH2, C-6), 34.0 (CH2, C-4),
46.4 (NCH2), 55.2 (OCH3), 55.7 (OCH3), 73.7 (CHO),
85.5 (CH, C-70), 91.0 (CH, C-50), 98.0 (CH, C-30), 113.5
(quat., C-3a0), 114.7 (CH2, C-1), 124.9 (CH, C-20), 137.2
(CH, C-2), 137.9 (quat., C-7a0), 153.7 (quat., C-40), 157.2
(quat., C-60), 170.7 (quat., C]O); m/z (EI+, %) 430 (28),
429 (M+, 100), 370 (5), 369 (12), 332 (2), 191 (4), 190 (6),
176 (3), 43 (6), 41 (2); HRMS (EI+): found M+, 429.2870.
C26H39NO4 requires 429.2879.
13
H); C NMR (100 MHz; CDCl3) d 24.9 (CH2, C-80), 26.9
(CH2, C-30), 29.2 (CH2, C-120), 29.3 (CH2, C-40, C-
50, C-60, C-70), 30.0 (CH2, C-20), 32.5 (CH2, C-90), 33.2
(CH2, C-110), 46.4 (CH2, C-10), 55.3 (6-OMe), 55.7 (4-
OMe), 84.6 (CH, C-7), 85.5 (CH, C-5), 91.0 (CH, C-100),
98.0 (CH, C-3), 113.5 (quat., C-3a), 115.5 (CH2, C-140),
117.8 (CH, C-500), 125.0 (CH, C-2), 130.6 (CH, C-400),
136.7 (CH, C-200), 137.1 (CH, C-130), 137.2 (quat., C-7a),
153.7 (quat., C-4), 157.2 (quat., C-6), 183.9 (quat., C]S);
m/z (EI+, %) 497 (M+, 1), 370 (28), 369 (M+ꢁC4H4N2OS,
100), 367 (25), 307 (18), 257 (16), 190 (12), 179 (13), 111
(22), 68 (12), 41 (14); HRMS (EI+): found M+, 497.2708.
C28H39N3O3S requires 497.2712.
4.1.3.2. 14-(40,60-Dimethoxy-10H-indol-10-yl)-2-oxo-
tetradecan-5-yl acetate 9. Using a similar method to that
described above for the preparation of analogue 8, Wacker
oxidation of alkene 22 (45 mg, 0.12 mmol) afforded the title
compound 9 (45 mg, 99%) as a dark wax; nmax (film) 2926,
2853, 1730, 1715, 1614, 1456, 1373, 1249, 1150, 1047, 937,
4.1.4.2. 4,6-Dimethoxy-1-(tetradec-130-enyl)-1H-in-
dole 23. Tributyltin hydride (0.053 mL, 0.2 mmol) and azo-
bisisobutyronitrile (catalytic) were added to a solution of
Barton–McCombie precursor 24 in toluene (2 mL) and the
mixture heated to reflux for 1 h. The reaction was then
filtered through a column of silica gel containing powdered
potassium fluoride (10% w/w) and washed with dichlorome-
thane (100 mL). The solvent was removed in vacuo and the
resultant oil dissolved in diethyl ether (10 mL) and washed
with saturated sodium bicarbonate (5 mL), water (5 mL)
and brine (5 mL). The combined aqueous layers were then
extracted with diethyl ether (4ꢂ5 mL) before the organic
layers were combined and dried over magnesium sulfate
and the solvent removed in vacuo. The resulting bright yel-
low oil was purified via flash chromatography using hexane–
ethyl acetate (4:1, Rf 0.90) eluent to afford the title com-
pound 23 (62 mg, 84%) as a colourless oil; nmax (film)
3074, 2926, 2853, 1740, 1623, 1589, 1500, 1463, 1372,
1
734 cmꢁ1; H NMR (400 MHz, CDCl3) d 1.19–2.04 (16H,
m, 13-H, 12-H, 11-H, 10-H, 9-H, 8-H, 7-H, 6-H), 2.14–
2.16 (2H, m, 4-H), 2.45 (2H, t, J¼7.4 Hz, 3-H), 2.88 (3H,
s, CH3CO), 2.96 (3H, s, OCOCH3), 3.86 (3H, s, OCH3),
3.91 (3H, s, OCH3), 4.01 (2H, t, J¼7 Hz, NCH2), 4.73–
4.84 (1H, m, CHOAc), 6.21 (1H, s, 50-H), 6.37 (1H, s, 70-
H), 6.48 (1H, s, 30-H), 6.88 (1H, s, 20-H); 13C NMR
(100 MHz, CDCl3) d 21.1 (OCOCH3), 25.2, 26.8, 27.9,
29.1, 29.3, 29.6, 29.9, 30.0 (CH2, C-13, C-12, C-11, C-10,
C-9, C-8, C-7, C-4), 34.2 (CH2, C-6), 36.5 (CH3, C-1),
39.4 (CH2, C-3), 46.4 (NCH2), 55.2 (OCH3), 55.7 (OCH3),
73.5 (CHOAc), 85.4 (CH, C-70), 90.9 (CH, C-50), 97.9
(CH, C-30), 113.4 (quat., C-3a0), 125.0 (CH, C-20), 137.2
(quat., C-7a0), 153.6 (quat., C-40), 157.1 (quat., C-60),
170.8 (quat., OC]O), 207.9 (C]O); m/z (EI+, %) 446
(5), 445 (M+, 9), 273 (3), 219 (40), 165 (7), 124 (9), 120
(13), 91 (14), 90 (16), 89 (24); HRMS (EI+): found M+,
445.2817. C26H39NO5 requires 445.2828.
1
1249, 1148, 1048; H NMR (400 MHz; CDCl3) d 1.29–
1.43 (4H, m, 60-H, 70-H), 1.56–1.59 (14H, m, 30-H, 40-H,
50-H, 80-H, 90-H, 100-H, 110-H), 1.78–1.79 (2H, m, 20-H),
2.03 (2H, q, J¼7.7 Hz, 120-H), 3.86 (3H, s, OCH3), 3.91
(3H, s, OCH3), 4.00 (2H, t, J¼7.1 Hz, 10-H), 4.90–5.01
(2H, m, 140-H), 5.76–5.84 (1H, m, 130-H), 6.22 (1H, d,
J¼1.5 Hz, 5-H), 6.40 (1H, d, J¼1.5 Hz, 7-H), 6.49 (1H, d,
J¼3.2 Hz, 3-H), 6.88 (1H, d, J¼3.2 Hz, 2-H); 13C NMR
(100 MHz; CDCl3) d 27.5 (CH2, C-30), 28.9 (CH2, C-40),
29.1 (CH2, C-50), 29.2 (CH2, C-60), 29.5 (CH2, C-70, C-80),
4.1.4. Procedure for the synthesis of analogues 10 and 11.
4.1.4.1.
4,6-Dimethoxy-1-(100-(N-imidazolylthio-
carbonyloxy)-tetradec-130-enyl)-1H-indole 24. 1,10-Thio-
carbonyldiimidazole 25 (0.10 g, 0.6 mmol) was added to a
solution of alcohol 12 (0.088 g, 0.2 mmol) in tetrahydrofuran