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3.3.1. (4R,11R)-4,11-Di-(tert-butoxycarbonyl)-amino-3,12-diethyl-6,9-dithia-tetradecan-3,12-diol 4
Work-up: purification by column chromatography (silica gel 60, eluent: n-hexane:EtOAc=3:2, Rf-
value: 0.41); yield: 7.29 g (66%); m.p. 93°C; [α]D20=−53.6 (c=1.04, CH2Cl2); IR (KBr): ν=3500–3300
1
cm−1 (OH, NH); 1670 (CO); H-NMR (CDCl3, 300 MHz): δ=0.78–0.91 (m, 12H, 4×CH2CH3);
1.33–1.64 (m, 8H, 4×CH2CH3); 1.43 (s, 18H, 2×C(CH3)3); 2.44 (s, 2×OH); 2.53–2.97 (m, 8H,
2×CH2SCH2); 3.73 (m, 2H, 2×CHN); 5.03 (s, 2H, 2×NH); 13C-NMR (CDCl3, 75.47 MHz): δ=7.58,
7.79 (4×CH2CH3); 27.55, 27.83 (4×CH2CH3); 28.36 (2×C(CH3)3); 32.55, 33.04 (2×CH2SCH2); 76.99
(2×COH); 79.37 (2×C(CH3)3); 156.28 (2×CO); MS (CI, i-butane): m/z (%)=553 (96) [MH+], 453 (100)
[MH+−C(O)OtBu]; anal. calc. for C26H52N2O6S2 (552.8): C, 56.48; H, 9.48; N, 5.07; S, 11.60. Found:
C, 56.69; H, 9.62; N, 5.05; S, 11.32.
3.3.2. (1R,8R)-1,8-Di-(tert-butoxycarbonyl)-amino-1,8-di-(10 -hydroxycyclopentyl)-3,6-dithia-octan 5
Work-up: purification by column chromatography (silica gel 60, eluent: n-hexane:EtOAc:CHCl3=
35:50:15, Rf-value: 0.68); yield: 8.24 g (60%); m.p. 150°C; [α]D20=−75.1 (c=1.03, CH2Cl2); IR (KBr):
ν=3600–3200 cm−1 (OH, NH); 1650 (CO); 1H-NMR (CDCl3, 300 MHz): δ=1.19–1.88 (m, 16H, 2×c-
pentyl-CH2); 1.44 (s, 18H, 2×C(CH3)3); 2.41–3.23 (m, 4H, 2×CH2SCH2); 3.86 (m, 2H, 2×CHN); 4.95
(m, 2H, 2×NH); 13C-NMR (CDCl3, 75.47 MHz): δ=28.38 (2×C(CH3)3); 23.53, 23.99, 30.99, 32.87,
36.14, 38.08 (8×c-pentyl-CH2, 2×CH2SCH2); 56.15 (2×CHN); 79.63 (2×C(CH3)3); 84.41 (2×COH);
156.39 (2×CO); MS (CI, i-butane): m/z (%)=549 (100) [MH+]; anal. calc. for C26H48N2O6S2 (548.8):
C, 56.90; H, 8.82; N, 5.10; S, 11.68. Found: C 57.03; H, 8.81; N, 5.14; S, 11.61.
3.3.3. (2R,9R)-2,9-Di-(tert-butoxycarbonyl)-amino-1,1,10,10-tetraphenyl-4,7-dithia-decan-1,10-diol 6
Work-up: purification by recrystallization from dichloromethane:n-hexane; yield: 12.98 g (87%); m.p.
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193°C; [α]20D=−61.2 (c=0.97, CH2Cl2); IR (KBr): ν=3400 cm−1 (NH, OH); 1660 (CO); H-NMR
(CDCl3, 300 MHz): δ=1.25 (s, 18H, 2×C(CH3)3); 2.48–2.57 (m, 3H, 6×CH2S); 2.75 (dd, J=3.01 Hz,
J=13.99 Hz, 2H, 2×CH2S); 4.08 (s, breit, 2H, 2×OH); 4.69 (m, 2H, 2×CHN); 7.08–7.47 (m, 20H,
aromat.-H); 13C-NMR (CDCl3, 75.47 MHz): δ=28.25 (2×C(CH3)3); 32.17, 33.16 (2×CH2SCH2); 56.14
(2×CHN); 79.79 (2×COH); 81.18 (C(CH3)3); 125.29, 125.69, 126.91, 127.05, 127.88, 128.15, 128.52
(20×aromat.-C); 144.72, 144.99 (4×q.-aromat.-C); 156.05 (2×CO); MS (CI, i-butane): m/z (%)=745
(100) [MH+]; anal. calc. for C42H52N2O6S2 (744.6): C, 67.75; H, 7.04; N, 3.76; S, 8.61. Found: C,
67.51; H, 7.04; N, 3.78; S, 8.58.
3.4. Products 7–9; general procedure
A portion of the respective N-Boc-protected amino alcohol 4–6 (10 mmol) was dissolved in 10 mL
CH2Cl2, 15 mL CF3CO2H was added at 0°C, and the resulting mixture was stirred overnight at r.t.
All volatile materials were removed in vacuo, the residue was taken up in 40 mL of 2 N NaOH and
after stirring for 15 min the resulting suspension was extracted with CH2Cl2 (4×25 mL). The combined
organic layers were dried over anhydrous MgSO4. Evaporation in vacuo afforded the crude bis-amino
alcohol which was purified by column chromatography or recrystallization (see below for individual
work-ups).
3.4.1. (4R,11R)-4,11-Diamino-3,12-diethyl-6,9-dithia-tetradecan-3,12-diol 7
Starting material: 1.27 g (2.3 mmol) 4; work-up: purification by column chromatography (silica gel
60, eluent: methanol:n-hexane=13:0.5, Rf-value: 0.46); yield: 0.63 g (78%); [α]D20=−115.2 (c=1.08,
1
CH2Cl2); IR (NaCl): ν=3600–3000 cm−1 (OH, NH); H-NMR (CDCl3, 300 MHz): δ=0.87 (t, J=7.57