Kadota et al.
J ) 11.2, 4.4, 4.4 Hz,1 H), 1.90-1.83 (m, 1 H), 1.76 (ddd, J )
14.8, 8.8, 2.0 Hz, 1 H), 1.70 (s, 3 H), 1.62-1.53 (m, 1 H), 1.49-
1.41 (m, 1 H), 1.21 (s, 3 H), 1.15 (ddd, J ) 14, 9.6, 4.4 Hz, 1 H),
0.93 (d, J ) 6.8 Hz, 3 H), 0.88 (s, 9 H), 0.84 (s, 9 H), 0.02 (s, 12
H); 13C NMR (100 MHz, CDCl3) δ 159.1, 143.1, 130.2, 129.3,
115.5, 113.8, 113.7, 82.3, 78.1, 76.8, 74.8, 72.4, 70.9, 70.7, 67.7,
55.3, 47.6, 36.1, 32.6, 30.9, 26.1, 25.8, 18.5, 18.4, 18.1, 17.9, 15.9,
-4.0, -4.6, -5.2, -5.2; HRMS (ESI TOF) calcd for C36H64O6-
Si2Na (M + Na+) 671.4139, found 671.4187.
1H), 3.41-3.38 (m, 2 H), 3.19 (dd, J ) 9.2, 2 Hz, 1 H), 3.14 (dd,
J ) 12.4, 4 Hz, 1 H), 3.11 (dd, J ) 11.2, 4.4 Hz, 1 H), 2.06-2.00
(m, 2 H), 1.92-1.86 (m, 1 H), 1.70 (ddd, J ) 14.8, 7.6, 2 Hz, 1
H), 1.63 (s, 3 H), 1.58-1.53 (m, 1 H), 1.48-1.41 (m, 2 H), 1.17
(s, 3 H), 0.86 (d, J ) 6.8 Hz, 3 H), 0.86 (s, 9 H), 0.80 (s, 9 H),
0.01 (s, 6 H); 13C NMR (100 MHz, CDCl3) δ 134.3, 121.2, 81.7,
79.5, 74.6, 73.3, 70.0, 69.5, 67.5, 66.9, 47.3, 35.6, 32.6, 31.1, 25.8,
18.0, 17.3, 17.2, 16.2, -3.8, -4.6; HRMS (ESI TOF) calcd for
C23H42O5SiNa (M + Na+) 449.2699, found 449.2667.
Tricycle 13. To a solution of 10 (278 mg, 0.43 mmol) in CH2-
Cl2 (4 mL) were added saturated NaHCO3 (1 mL) and DDQ (195
mg, 0.86 mmol), and the mixture was stirred for 1.5 h at 45 °C.
The reaction mixture was diluted with ether and then washed with
saturated NaHCO3, water, and brine. The organic layer was washed
with brine and dried over MgSO4. Concentration and chromatog-
raphy (hexane/EtOAc, 10:1) gave the corresponding alcohol (188
Sulfide 15. To a mixture of 14 (2.55 g, 6.0 mmol) in DMF (60
mL) at 0 °C were added (PhS)2 (2.87 g, 13 mmol) and Bu3P (3.3
mL, 13 mmol), and the mixture was stirred for 4 h at room
temperature. The mixture was diluted with ether and then washed
with H2O and brine. The organic layer was washed with brine and
dried over MgSO4. Concentration and chromatography (hexane/
EtOAc, 40:1 to 20:1) gave 15 (2.9 g, 95%): oil; Rf ) 0.29 (hexane/
mg, 84%): oil; Rf ) 0.36 (hexane/EtOAc, 4:1); [R]28 -28.0° (c
EtOAc, 10:1); [R]21D -24.6° (c 0.90, CHCl3); IR (neat) 2952 cm-1
;
D
1
0.90, CHCl3); IR (neat) 3448 cm-1; H NMR (400 MHz, CDCl3)
1H NMR (400 MHz, CDCl3) δ 7.31-7.11 (m, 5 H), 5.34 (dd, J )
3.6, 2 Hz, 1 H), 4.23 (bd, J ) 16.4 Hz, 1 H), 4.11 (dd, J ) 16.4,
2.8 Hz, 1 H), 3.93 (d, J ) 7.6 Hz, 1 H), 3.46 (ddd, J ) 10.8, 9.2,
5.2 Hz, 1 H), 3.21-3.16 (m, 2 H), 3.12 (dd, J ) 8.4, 4 Hz, 1 H),
3.09 (dd, J ) 9.6, 4.4 Hz, 1 H), 2.61 (dd, J ) 12.8, 8.4 Hz, 1 H),
2.08 (dd, J ) 12, 4.8 Hz, 1 H), 2.06-2.00 (m, 2 H), 1.83 (ddd,
J ) 14.4, 9.2, 2 Hz, 1 H), 1.69 (s, 3 H), 1.61 (q, J ) 11.2 Hz,
1 H), 1.49 (t, J ) 11.2 Hz, 1 H), 1.35 (ddd, J ) 14.4, 10, 4.8 Hz,
1 H), 1.21 (s, 3 H), 1.06 (d, J ) 6.8 Hz, 3 H) 0.87 (s, 9 H), 0.06
(s, 6 H); 13C NMR (100 MHz, CDCl3) δ 137.5, 134.4, 128.7, 128.7,
125.4, 121.1, 82.2, 79.4, 74.8, 73.4, 70.7, 69.6, 66.9, 47.4, 40.3,
38.9, 31.2, 29.9, 25.8, 20.6, 18.0, 17.3, 16.2, -3.8, -4.6; HRMS
(ESI TOF) calcd for C29H46O4SSiNa (M + Na+) 541.2784, found
541.2736.
δ 5.05 (s, 1 H), 5.04 (t, J ) 1.6 Hz, 1 H), 3.80 (d, J ) 9.2 Hz, 1
H), 3.53 (dd, J ) 9.6, 4.8 Hz, 1 H), 3.49-3.46 (m, 1 H), 3.41
(ddd, J ) 10.8, 9.2, 5.2 Hz, 1H), 3.33 (dd, J ) 9.6, 6.4 Hz, 1 H),
3.19 (ddd, J ) 9.6, 9.6, 2.0 Hz, 1 H), 2.17 (ddd, J ) 11.6, 4.4, 4.4
Hz 1 H), 2.09 (dd, J ) 11.6, 5.2 Hz, 1 H), 1.90-1.85 (m, 1 H),
1.80-1.73 (m, 1 H), 1.73 (s, 3 H), 1.64-1.55 (m, 2H), 1.50 (t,
J ) 11.2 Hz, 1 H), 1.23 (s, 3 H), 1.16 (ddd, J ) 14, 9.6, 4.4 Hz,
1 H), 0.92 (d, J ) 6.4 Hz, 3 H), 0.87 (s, 9 H), 0.84 (s, 9 H), 0.30
(s, 6 H), 0.17 (s, 6 H); 13C NMR (100 MHz, CDCl3) δ 142.7, 115.8,
82.4, 78.8, 78.2, 72.7, 70.9, 67.7, 67.4, 47.5, 36.1, 32.6, 32.5, 26.1,
25.8, 18.5, 18.3, 18.0, 17.1, 15.9, -4.0, -4.6, -5.2, -5.2; HRMS
(ESI TOF) calcd for C28H56O5Si2Na (M + Na+) 551.3564, found
551.3584.
To a suspension of KH (214 mg, 1.6 mmol, 30%, prewashed
with hexane) in THF (1.5 mL) at 0 °C were added allyl bromide
(0.14 mL, 1.6 mmol) and the alcohol obtained above (170 mg, 0.32
mmol) in THF (1.5 mL). After stirring for 1 h at the same
temperature, the reaction mixture was quenched with MeOH. The
mixture was diluted with ether and then washed with H2O and brine.
The organic layer was washed with brine, dried over MgSO4, and
concentrated to give crude 11, which was used for the next reaction
directly.
O,S-Acetal 18. To a mixture of 15 (222 mg, 0.43 mmol) in CCl4
(2 mL) was added NCS (57 mg, 0.43 mmol) in CH2Cl2 (0.8 mL).
The mixture was stirred for 0.5 h at room temperature to give a
solution of R-chlorosulfide 16, which was used for the next reaction
directly.
To a mixture of 17 (100 mg, 0.21 mmol), DTBMP (0.37 mL,
1.7 mmol), and MS4A (1.1 g) in CH2Cl2 (8 mL) at -78 °C was
added AgOTf (220 mg, 0.86 mmol), and the mixture was stirred
for 10 min at the same temperature. To the resulting mixture was
added 16 obtained above, and the mixture was allowed to warm to
-45 °C over 2 h. The mixture was then filtered through a silica
gel pad (ether). Concentration and chromatography (hexane/EtOAc,
40:1 to 4:1 containing 1% Et3N) gave 18 (134 mg, 91% from
reacted 17) and unreacted 17 (30 mg, 30%). 18: amorphous; Rf )
0.44 (hexane/EtOAc, 4:1); [R]22D +8.23° (c 0.98, CHCl3); IR (neat)
To a mixture of the allylic ether 11 in CH2Cl2 (64 mL) was added
12 (53 mg, 64 µmol), and the mixture was stirred for 20 h at room
temperature. The mixture was filtered through a short silica gel
column (ether) and concentrated. The residue was purified by
chromatography (hexane/EtOAc, 40:1) to give 13 (176 mg,
100%): oil; Rf ) 0.38 (hexane/EtOAc, 10:1); [R]22D -14.1° (c 1.00,
CHCl3); IR (neat) 2953 cm-1; 1H NMR (400 MHz, CDCl3) δ 5.31
(dd, J ) 3.2, 2 Hz, 1 H), 4.20 (bd, J ) 16.4 Hz, 1 H), 4.10 (dd,
J ) 16.4, 2.8 Hz, 1 H), 3.92 (d, J ) 8.8 Hz, 1 H), 3.51 (dd, J )
10, 4.8 Hz, 1H), 3.43 (ddd, J ) 10.8, 9.2, 5.2 Hz, 1 H), 3.21-3.14
(m, 2 H), 3.12 (dd, J ) 12, 3.6 Hz, 1 H), 2.09-2.03 (m, 2 H),
1.90-1.83 (m, 1 H), 1.75 (ddd, J ) 14.4, 9.2, 2.4 Hz, 3 H), 1.68
(s, 3 H), 1.62 (q, J ) 12 Hz, 1 H), 1.47 (t, J ) 11.2 Hz, 3 H), 1.21
(s, 3 H), 1.15 (ddd, J ) 13.6, 10, 4.4 Hz, 1 H), 0.91 (d, J ) 6.4
Hz, 3 H), 0.86 (s, 9 H), 0.84 (s, 9 H), 0.04 (s, 6 H), 0.00 (s, 6 H);
13C NMR (100 MHz, CDCl3) δ 134.4, 121.1, 82.6, 79.4, 74.8, 73.5,
71.0, 69.6, 67.7, 66.9, 47.4, 36.2, 32.5, 31.3, 26.1, 25.8, 18.5, 18.3,
17.9, 17.3, 16.3, -3.9, -4.5, -5.2, -5.2; HRMS (ESI TOF) calcd
for C29H56O5Si2Na (M + Na+) 563.3564, found 563.3514.
Alcohol 14. To a mixture of 13 (309 mg, 0.57 mmol) in CH2Cl2
(6 mL) and MeOH (6 mL) at 0 °C was added CSA (26 mg, 0.11
mmol). After stirring for 2.5 h at the same temperature, the reaction
mixture was quenched with Et3N and filtered through a short silica
gel column (ether). Concentration and chromatography (hexane/
EtOAc, 4:1) gave 14 (230 mg, 95%): oil; Rf ) 0.23 (100% hexane
1
2952 cm-1; H NMR (400 MHz, CDCl3) δ 7.44-7.15 (m, 15 H),
5.81 (dd, J ) 17.2, 10.4 Hz, 1 H), 5.25 (s, 1 H), 5.16 (dd, J )
17.2, 1.6 Hz, 1 H), 4.91 (dd, J ) 10.8, 1.6 Hz, 1 H), 4.85 (d, J )
4 Hz, 1 H), 4.44 (d, J ) 11.6 Hz, 1 H), 4.34 (s, 2 H), 4.28 (d, J )
11.6 Hz, 1 H), 4.13 (bd, J ) 14.8 Hz, 1 H), 4.01 (dd, J ) 16, 2.4
Hz, 1 H), 3.86 (d, J ) 8 Hz, 1 H), 3.76 (dd, J ) 10.2, 4.8 Hz, 1
H), 3.54-3.36 (m, 4 H), 3.20 (ddd, J ) 9.2, 9.2, 2.0 Hz, 1 H),
3.12 (ddd, J ) 12, 8.4, 4.0 Hz, 1 H), 3.06 (dd, J ) 12.4, 4.0 Hz,
1 H), 3.00 (dd, J ) 12.4, 3.6 Hz, 1 H), 2.22-2.16 (m, 1 H), 2.11
(dd, J ) 14.7, 7.6, 2.4 Hz, 1 H), 2.06-1.98 (m, 3 H), 1.87-1.78
(m, 2 H), 1.62 (s, 3 H), 1.58-1.46 (m, 2 H), 1.43-1.35 (m, 2 H),
1.31-1.23 (m, 1 H), 1.20 (s, 3 H), 1.15 (s, 3 H), 1.12 (dd, J ) 4.8,
1.6 Hz, 1 H), 1.10 (s, 3 H), 1.05 (s, 3 H), 0.98 (d, J ) 6.8 Hz, 3
H), 0.79 (s, 9 H), 0.00 (s, 6 H); 13C NMR (100 MHz, CDCl3) δ
144.9, 138.5, 138.5, 135.8, 134.3, 133.0, 128.8, 128.2, 128.2, 127.6,
127.5, 127.4, 127.4, 127.2, 121.2, 111.9, 93.1, 83.0, 79.6, 77.8,
77.4, 76.9, 76.4, 74.8, 73.4, 73.0, 73.0, 71.3, 71.1, 71.0, 69.6, 66.9,
66.1, 47.5, 40.2, 36.5, 35.4, 31.3, 26.1, 25.9, 23.1, 19.7, 18.1, 17.5,
17.4, 17.3, 16.3, -4.0, -4.4; HRMS (ESI TOF) calcd for C58H82-
O9SSiNa (M + Na+) 1005.5346, found 1005.5369.
to hexane/EtOAc, 4:1); [R]21 -2.1° (c 1.00, CHCl3); IR (neat)
D
3458 cm-1; H NMR (400 MHz, CDCl3) δ 5.28 (dd, J ) 3.6, 2
Mixed Acetal 21. To a mixture of 18 (174 mg, 177 mmol) in
THF (1.8 mL) was added TBAF (1.0 M in THF, 0.47 mL, 470
mmol). After stirring for 20 h at room temperature, the reaction
1
Hz, 1 H), 4.16 (bd, J ) 16.4 Hz, 1 H), 4.05 (dd, J ) 16.4, 2.8 Hz,
1 H), 3.88 (d, J ) 8.8 Hz, 1 H), 3.47 (ddd, J ) 10.8, 8.8, 4.8 Hz,
4186 J. Org. Chem., Vol. 71, No. 11, 2006