5126
2.90 (s, (CH3)2-N), 3.75 (dd, J = l l , 4.3Hz, H-6), 3.79 (dd, J = l l , 5.5Hz, H - 6 ' ) , 3.80 (dd,
J=4. 0, 2. 1Hz, H-3), 3.98 (dd, J=4. 6, 4.0Hz, H-4), 4.41 (dd, J=8. 2, 2.1Hz, H-2), 4.96
(dd, J=8. 2, 3.2Hz, H - I ) , in 86% yield. Probably, the success of this ring contraction
reaction is due to the fact that the fused system of two five membered rings like 14 is more
stable than that of the six and five membered rings like 12.
Finally, the protective groups of 14 were removed by successive treatments with 1M
HC1 in aq. THF and H2-10% Pd on carbon in 0.1M HC1-H20 to give 1 as monohydrochloride
in 90% overall yield. Spectral and physical properties including the sign of the specific
rotation of the compound prepared were identical in all respects with those reported 1,3 for
the natural specimen. In conclusion, the first synthesis of chiral allosamizoline (1) was
achieved, which gave an unambiguous evidence for its absolute configuration proposed.
References and Notes
1.
S. Sakuda, A. Isogai, S. Matsumoto, and A. Suzuki, Tetrahedron Lett., 27, 2475 (1986); S. Sakuda,
A. Isogai, S. Matsumoto, and A. Suzuki, J. Antibiotic., 40, 296 (1987)i
2.
D. Koga, A. Isogai, S. Sakuda, S. Matsumoto, A. Suzuki, S. Kimura, and A. Doi, Agric. Biol. Chem.,
51, 471 (1987);/G. W. Goody, L. J. Brydon, and L. H. Chappell, Mol. Biochem. Parasitol., 29, 223
(1988);/K~.Dickinson, V. Keer, C. A. Hitchcock, and J. Adams, J. Gen. Microbiol., 135, 1417 (1989~;
A. Isogai, M. Sato, S. Sakuda, J. Nakayama, and A. Suzuki, Agric. Biol. Chem., 53, 2825 (1989)i
E. Cabib, A. Sburlati, B. Bowers, and J. Silverman, J. CellBiol., 108, 1665 (1989);'S. Sakuda,
Y. Nishimoto, M. Ohi, M. Watanabe, S. Takayama, A. Isogai, and Y. Yamada, Agric. Biol. Chem.,
54, 1333 (1990);/13. A. Griffith, and S. J. Danishefsky, J. Am. Chem. Soc., 112, 5811 (1990).
S. Sakuda, A. Isogai, T. Makita, S. Matsumoto, K. Koseki, H. Kodama, and A. Suzuki,
Agric. Biol. Chem., 51, 3251 (1987).
3.
4.
5.
B.M. Trost, and D. L. Van Vranken, J. Am. Chem. Soc., 112, 1261 (1990).
S. Sakuda, A. Isogai, S. Matsumoto, A. Suzuki, K. Koseki, H. Kodama, and Y. Yamada,
Agric. Biol. Chem., 52, 1615 (1988).
6.
This compound was synthesized from the known methyl 2-methoxycarbonylamino glycoside ( D. Ikeda,
T. Tsuchiya, and S. Umezawa, Bull. Chem. Soc. Jpn., 44, 2529 (1971).) in 3 steps ; 1) PhCH(OMe)2,
p-TsOH, DMF, 2) BnBr, BaO, Ba(OH)2, DMF, 3) KOH, MeOC2H4OH, aq. dioxane.
All new compounds gave satisfactory spectral data and elemental analyses.
7.
8.
9.
S. Hanessian, and P. Lavallee, Methods Carbohydr. Chem., 7, 49 (1976).
E.J. Corey, H. Cho, C. Rucker, and D. H. Hua, Tetrahedron Lett., 22, 3455 (1981).
10. D.H. Barton, S. Augy-Dorey, J. Camara, P. Dalko, J. M. Delaumeny, S. D. Gero, B. Quiclet-Sire, and
P. Stutz, Tetrahedron, 46, 215 (1990).
I 1. S. Kobayashi, K. Kamiyama, and M. Ohno, J. Org. Chem., 55, 1169 (1990).
12. Dreiding model examination reveals that the tosyloxy group at C-6 in 12 is in nearly antiperiplanar
relationship to the C4-C5 bond in the half-chair-like conformation.
13. H.H. Baer, D. J. Astles, H. -C. Chin, and L. Siemsen, Can. J. Chem., 63, 432 (1985).
(Received in Japan 13 June 1991)