P. Breton et al. / Tetrahedron 63 (2007) 5709–5729
5725
4.3, 2.7 Hz, 1H), 3.52 (dd, J¼10.3, 4.4 Hz, 1H), 3.51–3.48
(m, 1H), 3.47 (dd, J¼10.3, 6.8 Hz, 1H), 2.60 (d, J¼6.1 Hz,
1H), 1.98–1.89 (comp, 4H), 1.70–1.62 (comp, 3H), 1.57–
1.52 (m, 1H), 1.44 (s, 3H), 1.03 (d, J¼6.7 Hz, 3H), 0.96 (t,
J¼7.3 Hz, 3H), 0.95 (d, J¼5.8 Hz, 3H), 0.87 (s, 9H), 0.86
(d, J¼6.9 Hz, 3H), 0.76 (d, J¼7.0 Hz, 3H), 0.38 (s, 3H),
0.32 (s, 3H); 13C NMR (125 MHz) d 154.3, 137.4, 128.5,
127.8, 127.7, 94.8, 86.8, 85.1, 83.7, 76.6, 71.7, 70.1, 64.7,
44.2, 37.9, 36.4, 36.0, 31.2, 25.9, 23.6, 19.3, 18.2, 12.7,
11.8, 11.1, 9.9, ꢀ5.5, ꢀ5.5; IR (neat) n 3460, 3060,
1800, 1460, 1390, 1260, 850 cmꢀ1; mass spectrum (CI)
m/z 503.34062 [C26H51O7Si (MꢀPhCH2O) requires
503.34041]; [a]2D5 +26.6 (c 1.59, CHCl3).
(comp, 5H), 6.76 (s, 2H), 5.98 (s, 1H), 4.73 (d, J¼6.6 Hz,
1H), 4.69 (d, J¼6.6 Hz, 1H), 4.68 (d, J¼12.3 Hz, 1H),
4.62 (d, J¼12.3 Hz, 1H), 4.01 (dd, J¼10.2, 2.0 Hz, 1H),
3.84 (ddd, J¼7.2, 7.1, 1.2 Hz, 1H), 3.77 (dd, J¼9.7,
3.0 Hz, 1H), 3.62 (dd, J¼9.7, 4.1 Hz, 1H), 3.61 (s, 1H),
3.50 (d, J¼1.8 Hz, 1H), 3.30 (d, J¼11.3 Hz, 1H), 2.64–
2.54 (m, 1H), 2.45 (s, 6H), 2.40 (s, 1H), 2.21 (s, 3H), 1.91
(qd, J¼7.1, 2.0 Hz, 1H), 1.84–1.78 (m, 1H), 1.74–1.62
(comp, 2H), 1.56 (d, J¼14.4 Hz, 1H), 1.44–1.36 (m, 1H),
1.25 (d, J¼7.0 Hz, 3H), 1.19 (dd, J¼14.4, 6.5 Hz, 1H),
1.12 (s, 3H), 1.06 (d, J¼6.5 Hz, 3H), 1.04 (d, J¼7.0 Hz,
3H), 0.90 (s, 9H), 0.81 (d, J¼7.5 Hz, 3H), 0.80 (d, J¼
6.9 Hz, 3H), 0.07 (s, 6H); 13C NMR (125 MHz) d 138.4,
137.8, 136.9, 132.0, 129.8, 128.3, 127.6, 127.4, 95.5,
94.6, 85.6, 78.9, 78.8, 76.5, 74.2, 70.3, 69.5, 44.8, 37.4,
35.163, 28.1, 26.5, 26.2, 25.9, 22.3, 20.9, 20.6, 19.8, 18.2,
14.3, 10.8, 10.5, 7.4, ꢀ5.6, ꢀ5.6; IR (neat) n 3430, 1450,
1255, 1110 cmꢀ1; mass spectrum (CI) m/z 715.49678
[C42H71O7Si (M+1) requires 715.49691], 407, 393, 365
(base); [a]2D5 ꢀ25.7 (c 0.72, CHCl3).
4.1.28. (2S,3R,4R,6R,7S,8S,9S,10S,11R)-11-(Benzyloxy-
methoxy)-1-[(tert-butyldimethylsilyl)oxy]-3,4-(carbonyl-
dioxy)-2,4,6,8,10-pentamethyl-7,9-{[(R)-2,4,6-trimethyl-
benzylidene]dioxy}tridecane (26). A solution of 1,3-anti-
diol 25 (335 mg, 0.549 mmol), mesitylaldehyde dimethyl
acetal (426 mg, 2.20 mmol), and CSA (64 mg, 0.274
mmol) in CH2Cl2 (20 mL) was stirred at room temperature
for 3 h. Saturated aqueous NaHCO3 (ca. 4 mL) was added,
and the layers were separated; the aqueous layer was ex-
tracted with CH2Cl2 (4ꢂ10 mL). The combined organic
layers were washed with brine (5 mL), dried (Na2SO4), fil-
tered, and concentrated. The residue was purified by flash
column chromatography, eluting with hexanes/EtOAc
(20:1) to provide 367 mg (90%) of acetal 26 as a white
4.1.30. (2S,3R,4R,6R,7S,8S,9S,10S,11R)-11-(Benzyloxy-
methoxy)-1-[(tert-butyldimethylsilyl)oxy]-3-[(20-O-meth-
oxycarbonyl-a-D-desosaminyl)oxy]-2,4,6,8,10-penta-
methyl-7,9-{[(R)-2,4,6-trimethylbenzylidene]dioxy}tri-
˚
decan-4-ol (48). To a suspension of freshly activated 4 A
molecular sieves (2.2 g) and AgOTf (1.03 g, 4.0) in
CH2Cl2 (3.3 mL) and toluene (3.3 mL), was added a solution
of diol 47 (145 mg, 0.203 mmol), desosamine thioglycoside
35 (398 mg, 1.22 mmol), and 2,6-di-tert-butylpyridine
(0.275 mL, 1.22 mmol) in CH2Cl2 (3.3 mL) by syringe
pump (0.052 mL/min). The reaction flask was wrapped
with aluminum foil to protect the mixture from light, and
the reaction was stirred at room temperature for 4 h after
the completion of addition. After adding Et3N (ca. 3 mL),
the resulting mixture was filtered through Celite, eluting
with EtOAc. The filtrate was washed with saturated aqueous
NaHCO3 (4ꢂ4 mL), dried (Na2SO4), filtered, and concen-
trated under reduced pressure. The residue was purified by
flash chromatography, eluting with hexanes/EtOAc (2:1),
to provide 36 mg (25%) of starting 47, 69 mg (42%) of 48,
and 57 mg (35%) of 49 as colorless oils; 1H NMR
(500 MHz) d 7.33–7.23 (comp, 5H), 6.75 (s, 2H), 5.98 (s,
1H), 4.70 (d, J¼6.6 Hz, 1H), 4.67 (dd, J¼10.6, 7.6 Hz,
1H), 4.66 (d, J¼6.6 Hz, 1H), 4.66 (d, J¼12.4 Hz, 1H),
4.63 (d, J¼12.4 Hz, 1H), 4.36 (d, J¼7.6 Hz, 1H), 4.09 (s,
1H), 4.08 (dd, J¼9.7, 1.8 Hz, 1H), 3.82 (ddd, J¼7.2, 7.1,
0.95 Hz, 1H), 3.75 (s, 3H), 3.69 (s, 1H), 3.59–3.47 (m,
1H), 3.41 (dd, J¼10.0, 9.9 Hz, 1H), 3.33 (dd, J¼9.9,
5.4 Hz, 1H), 3.24 (d, J¼11.4 Hz, 1H), 2.93–2.81 (m, 1H),
2.74 (ddd, J¼12.2, 10.6, 4.4 Hz, 1H), 2.42 (s, 6H), 2.29 (s,
6H), 2.20 (s, 3H), 2.07 (qd, J¼7.2, 1.8 Hz, 1H), 1.88–1.72
(comp, 2H), 1.69–1.60 (comp, 2H), 1.42–1.35 (comp, 2H),
1.24 (d, J¼6.1 Hz, 3H), 1.20 (d, J¼7.1 Hz, 3H), 1.17 (s,
3H), 1.10 (dd, J¼13.9, 4.6 Hz, 1H), 1.04 (d, J¼6.7 Hz,
3H), 0.90 (s, 9H), 0.80 (t, J¼7.5 Hz, 3H), 0.77 (d,
J¼7.0 Hz, 3H), 0.72 (d, J¼6.9 Hz, 3H), 0.62 (s, 3H), 0.43
(s, 3H); 13C NMR (125 MHz) d 155.3, 138.5, 137.6, 137.0,
132.2, 129.7, 128.2, 127.7, 127.3, 103.2, 95.2, 94.5, 87.5,
86.2, 78.5, 76.0, 75.3, 73.2, 69.7, 69.4, 65.1, 63.1, 54.6,
44.0, 40.6, 37.5, 36.5, 30.5, 27.5, 26.2, 25.8, 25.6, 22.8,
20.9, 20.7, 20.6, 20.3, 18.1, 14.3, 10.5, 9.9, 7.2, ꢀ5.3; IR
(neat) n 3420, 1750, 1440, 1270, 1100 cmꢀ1; mass spectrum
1
foam; H NMR (500 MHz) d 7.33–7.22 (comp, 5H), 6.79
(s, 2H), 5.95 (s, 1H), 4.72 (s, 2H), 4.72 (d, J¼12.5 Hz,
1H), 4.66 (d, J¼12.5 Hz, 1H), 4.32 (d, J¼6.0 Hz, 1H),
4.01 (dd, J¼10.2, 2.0 Hz, 1H), 3.82 (td, J¼7.1, 1.0 Hz,
1H), 3.53 (dd, J¼10.3, 4.2 Hz, 1H), 3.46 (dd, J¼10.3,
6.4 Hz, 1H), 3.29 (d, J¼11.1 Hz, 1H), 2.64–2.50 (m, 1H),
2.47 (s, 6H), 2.23 (s, 3H), 1.94 (qddd, J¼6.8, 6.4, 6.0,
4.2 Hz, 1H), 1.77 (qd, J¼7.0, 2.0 Hz, 1H), 1.73–1.64
(comp, 3H), 1.54 (dd, J¼14.9, 7.6 Hz, 1H), 1.43–1.34 (m,
1H), 1.32 (s, 3H), 1.26 (d, J¼7.0 Hz, 3H), 1.06 (d,
J¼6.6 Hz, 3H), 1.04 (d, J¼6.8 Hz, 3H), 0.87 (s, 9H), 0.85
(d, J¼7.0 Hz, 3H), 0.81 (t, J¼7.4 Hz, 3H), 0.36 (s, 3H),
0.24 (s, 3H); 13C NMR (125 MHz) d 153.6, 138.5, 138.0,
136.9, 131.6, 129.9, 128.2, 128.2, 127.4, 127.3, 95.9, 95.0,
86.5, 85.8, 84.6, 79.6, 76.2, 69.4, 64.7, 44.5, 37.6, 35.8,
38.5, 27.7, 26.3, 25.8, 20.9, 20.6, 19.2, 19.1, 18.3, 14.3,
13.1, 10.5, 7.4, ꢀ5.5, ꢀ5.6; IR (neat) n 1800, 1600, 1455,
1380, 1250, 840 cmꢀ1; mass spectrum (CI) m/z 740.4674
[C43H68O8Si (M+1) requires 740.4684]; [a]2D3 +25.5 (c
1.78, CHCl3).
4.1.29. (2S,3R,4R,6R,7S,8S,9S,10S,11R)-11-(Benzyloxy-
methoxy)-1-[(tert-butyldimethylsilyl)oxy]-2,4,6,8,10-
pentamethyl-7,9-{[(R)-2,4,6-trimethylbenzylidene]di-
oxy}tridecan-3,4-diol (47). LiBH4 (7 mg, 0.314 mmol) was
added to a solution of the cyclic carbonate 26 (193 mg,
0.26 mmol) in anhydrous ether (25 mL) at room temperature
under Ar. After stirring 5 h, the reaction was cooled to 0 ꢁC,
and saturated aqueous NH4Cl (ca. 6 mL) was added. The
layers were separated, and the aqueous layer was extracted
with CH2Cl2 (10ꢂ10 mL). The combined organic layers
were dried (Na2SO4) and concentrated under reduced pres-
sure. The residue was purified by flash chromatography
with hexanes/ethyl acetate (4:1) to give 170 mg (92%) of
47 as a white foam; 1H NMR (500 MHz) d 7.30–7.23