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T. Ogamino, S. Nishiyama / Tetrahedron Letters 46 (2005) 1083–1086
10. Okamoto, K. T.; Clardy, J. Tetrahedron Lett. 1987, 28,
6. (a) Ogamino, T.; Ishikawa, Y.; Nishiyama, S. Heterocycles
2003, 61, 73–78; (b) Ogamino, T.; Nishiyama, S. Tetrahe-
dron 2003, 59, 9419–9423.
4969–4972.
11. Goldenstein, K.; Fendert, T.; Proksch, P.; Winterfeldt, E.
Tetrahedron 2000, 56, 4173–4185.
7. Related synthetic studies: (a) Murakata, M.; Yamada, K.;
Hoshino, O. J. Chem. Soc., Chem. Commun. 1994, 443–
444; (b) Murakata, M.; Yamada, K.; Hoshino, O.
Tetrahedron 1996, 52, 14713–14722; (c) Murakata, M.;
Tamura, M.; Hoshino, O. J. Org. Chem. 1997, 62, 4428–
4433; (d) Murakata, M.; Yamada, K.; Hoshino, O.
Heterocycles 1998, 47, 921–931; (e) Wasserman, H. H.;
Wahng, J. J. Org. Chem. 1998, 63, 5581–5586; (f)
Boehlow, T. R.; Jonathan Harburn, J.; Spilling, C. D. J.
Org. Chem. 2001, 66, 3111–3118.
12. Compound 13: IR (film) 3410, 1701, 1670 cmÀ1
;
1H NMR (400 MHz, DMSO-d6) d 1.48 (4H, br s),
3.20 (4H, br s), 3.60 (2H, d, J = 18.0 Hz), 3.67 (2H,
d, J = 18.0 Hz), 3.92 (2H, d, J = 3.6 Hz), 4.12 (2H,
dd, J = 2.4, 4.0 Hz), 7.48 (2H, d, J = 2.4 Hz), 8.64
(2H, t, J = 6.0 Hz); 13C NMR (100 MHz, DMSO-d6)
d 26.3, 38.5, 43.3, 52.9, 56.8, 83.9, 122.7, 143.7, 154.8,
158.2, 185.9.
13. The reason of the low yield of this condensation reaction
may be the instability of carbonic acid 12 or 16. In the case
of 16, the nitrile 17 was easily produced by decarboxyl-
ation and the following heterolysis of the N–O bond, as a
by-product. Improvement of the condition is in
progress.
14. Synthetic product 13 might be a diastereomer mixture.
Unfortunately, up to now we have not been able to
accomplish their separation. This problem was also
encountered in the synthesis of aerothionin 2.5
8. Forrester, A. R.; Thomson, R. H.; Woo, S. O. J. Chem.
Soc., Perkin Trans. 1 1975, 4, 2340–2348.
9. Synthetic sample of 1: IR (film) 3375, 1703, 1666 cmÀ1; 1H
NMR (400 MHz, DMSO-d6) d 1.52 (4H, br s), 3.19 (4H,
br s), 3.41 (2H, d, J = 18.4 Hz), 3.56 (2H, d, J = 18.4 Hz),
3.81 (2H, d, J = 4.0 Hz), 4.12 (2H, d, J = 2.8, 4.0 Hz), 7.29
(2H, d, J = 2.8 Hz), 8.61 (2H, t, J = 6.0 Hz); 13C NMR
(100 MHz, DMSO-d6) d 26.3, 38.5, 43.3, 51.8, 55.0, 85.4,
119.7, 144.2, 154.6, 159.7, 185.8.