P. Wei, R. J. Kerns / Tetrahedron Letters 46 (2005) 6901–6905
6905
1H), 4.85 (d, 1H), 7.30–7.50 (m, 11H), 7.71 (m, 4H). Mass
3.64 (t, 1H), 4.09–4.29 (m, 3H), 4.34 (d, 1H), 4.41 (d, 2H),
4.52 (d, 1H), 4.80 (d, 1H), 4.91 (t, 1H), 5.76 (s, 1H), 5.91 (m,
1H), 6.90–7.36 (m, 10H). Mass spec. (ESI) m/z 509.4
(M+Na+).
spec. (ESI) m/z 508.3 (M+H+).
1
Compound (12) Rf = 0.27 (EtOAc); H NMR (CDCl3) d
1.08 (s, 9H), 1.96 (s, 3H), 3.45–3.52 (m, 2H), 3.63 (m, 2H),
3.91–4.04 (dd, dd, 2H), 4.14 (dd, 1H), 4.40 (d, 1H), 4.55 (d,
1H), 4.81 (d, 1H), 5.75 (s, 1H), 7.32–7.46 (m, 11H), 7.71 (m,
4H). Mass spec. (ESI) m/z 572.5 (M+Na+).
10. Crich, D.; Vinod, A. U. J. Org. Chem. 2005, 70, 1291–
1296.
11. Evans, D. A.; Sjogren, E. B.; Bartroli, J.; Dow, R. L.
Tetrahedron Lett. 1986, 27, 4957–4960.
12. Evans, D. A.; Britton, T. C.; Ellman, J. A. Tetrahedron
Lett. 1987, 28, 6141–6144.
13. Sypniewski, M.; Penke, B.; Simon, L.; Rivier, J. J. Org.
Chem. 2000, 65, 6595–6600.
14. Yeung, B. K. S.; Adamski-Werner, S. L.; Bernard, J. B.;
Poulenat, G.; Petillo, P. A. Org. Lett. 2000, 2, 3135–3138.
15. Boysen, M.; Gemma, E.; Lahmann, M.; Oscarson, S.
Chem. Commun. 2005, 3044–3046.
16. Mikamo, M. Carbohydr. Res. 1989, 191, 150–153; Rowell,
R. M.; Feather, M. S. Carbohydr. Res. 1967, 4, 486–491.
17. Ichikawa, Y.; Matsukawa, Y.; Isobe, M. Synlett 2004, 6,
1019–1022; Pinter, I.; Kovacs, J.; Toth, G. Carbohydr.
Res. 1995, 273, 99–108.
18. Ellestad, G. A.; Cosulich, D. B.; Broschard, R. W.;
Martin, J. H.; Kunstmann, M. P.; Morton, G. O.;
Lancaster, J. E.; Fulmor, W.; Lovell, F. M. J. Am. Chem.
Soc. 1978, 100, 2515–2524; Fernandes, P. B.; Swanson, R.
N.; Hardy, D. J.; Hanson, C. W.; McDaniel, D.; Beyer, J.;
Chen, R. H. J. Antibiot. 1989, 42, 538–541; Chen, R. H.;
Whittern, D. N.; Buko, A. M.; McAlpine, J. B. J. Antibiot.
1989, 42, 533–537.
Compound (13a) Rf = 0.21 (1:1, EtOAc/Hexanes); 1H
NMR (CDCl3) d 1.09 (s, 9H), 1.94 (s, 3H), 3.62–3.69 (m,
2H), 3.77 (s, 3H), 3.84–3.96 (m, 2H), 4.57 (dd, 2H), 4.71 (d,
1H), 4.89 (d, 1H), 5.06–5.34 (m, 4H), 5.51 (d, 1H), 5.84 (m,
1H), 7.31–7.48 (m, 11H), 7.71 (m, 4H). Mass spec. (ESI)
m/z 714.5 (M+Na+).
Compound (13b) Rf = 0.44 (3:1, EtOAc/Hexanes); 1H
NMR (CDCl3) d 1.09 (s, 9H), 3.36–3.47 (m, 2H), 3.65–3.69
(m, 4H), 3.96–4.14 (m, 2H), 4.12 (dd, 1H), 4.46 (d, 1H),
4.56 (d, 1H), 4.86 (d, 1H), 7.30–7.47 (m, 11H), 7.69 (m,
4H). Mass spec. (ESI) m/z 588.6 (M+Na+).
Compound (17a) Rf = 0.42 (EtOAc); 1H NMR (CDCl3) d
2.09 (s, 3H), 2.12 (s, 3H), 2.82 (s, 2H), 3.48–3.55 (m, 1H),
3.59–3.65 (m, 1H), 3.76 (t, 3H), 4.15–4.20 (dd, 1H), 4.26–
4.32 (dd, 1H), 4.35–4.47 (m, 1H), 4.48 (d, 1H), 4.52 (d, 1H),
4.88 (d, 1H), 4.95 (dd, 1H), 5.78 (s, 1H), 7.34–7.40 (m, 5H).
Mass spec. (ESI) m/z 419.4 (M+Na+).
Compound (17b) Rf = 0.46 (EtOAc); 1H NMR (CDCl3) d
1.50–1.59 (m, 5H), 2.09 (s, 3H), 2.15 (s, 3H), 3.01 (d, 1H),
3.19–3.28 (m, 4H), 3.44–3.65 (m, 2H), 3.89 (dd, 1H), 4.25–
4.38 (dd, 1H), 4.48–4.64 (m, 3H), 4.88 (d, 1H), 4.96 (dd,
1H), 7.28–7.34 (m, 5H). Mass spec. (ESI) m/z 487.4
(M+Na+).
19. Smith, T. K.; Gerold, P.; Crossman, A.; Paterson, M. J.;
Borissow, C. N.; Brimacombe, J. S.; Ferguson, M. A. J.;
Schwarz, R. T. Biochemistry 2002, 41, 12395–12406.
1
Compound (17c) Rf = 0.54 (EtOAc); H NMR (CDCl3) d
2.01 (s, 3H), 2.08 (s, 3H), 3.35 (m, 1H), 3.51–3.55 (m, 1H),