H. Okamura et al. / Tetrahedron 59 (2003) 10159–10164
10163
at room temperature. The mixture was stirred for 15 h, and
filtered through a pad of silica gel. The filtrate was
evaporated and the residue was purified via silica gel
column chromatography (hexane/ethyl acetate, 1:1) to give
calcd for C7H6O4: C, 54.55; H, 3.92. Found: C, 54.69; H,
4.00.
1
12 (3.6 mg, 24% after three steps) as a colorless oil. H
Acknowledgements
NMR (CDCl3): d 6.73 (m, 1H), 4.95 (br d, J¼12.0 Hz, 1H),
4.80 (br d, J¼12.0 Hz, 1H), 3.80–3.85 (m, 2H), 2.10 (s,
3H).
We thank Professor Tsutomu Katsuki and Professor Junji
Inanaga of Kyushu University, Japan for elemental analysis.
3.1.6. (7R,8S,9S)-9-tert-Butyldimethylsilyloxy-2,6-dioxo-
7,8-epoxy-1,3-dioxa-spiro[4.5]decane (13). To a solution
of 11 (51.3 mg, 0.178 mmol) in CH2Cl2 were added DMAP
(2.1 mg, 0.0178 mmol) and N,N0-carbonyldiimidazole
(43.3 mg, 0.267 mmol). After stirring for 1 day, the
resulting mixture was directly purified by silica gel column
chromatography to give a 6:1 diastereomeric mixture of 13
(46.8 mg, 84%) as a colorless oil. Rf 0.60 (CH2Cl2/ethyl
acetate, 20:1); IR (KBr): 2951, 1822, 1736 cm21; Major
References
1. Thebtaranonth, C.; Thebtaranonth, Y. Acc. Chem. Res. 1986,
19, 84–90.
2. Nagasawa, H.; Suzuki, A.; Tamura, S. Agric. Biol. Chem.
1978, 42, 1303–1304.
1
diastereomer: H NMR (CDCl3): d 4.68 (br d, J¼3.2 Hz,
3. (a) Nakamori, K.; Matsuura, H.; Yoshihara, T.; Ichihara, A.;
Koda, Y. Phytochemistry 1994, 35, 835–839. (b) Yoshihara,
T.; Ohmori, F.; Nakamura, K.; Amanuma, M.; Tsutsumi, T.;
Ichihara, A.; Matsuura, H. J. Plant Growth Reg. 2000, 19,
457–461.
1H), 4.42 (dd, J¼9.5, 1.5 Hz, 1H), 4.19 (d, J¼9.5 Hz, 1H),
3.56 (m, 1H), 3.49 (d, J¼3.7 Hz, 1H), 2.64 (br dd, J¼13.9,
2.7 Hz, 1H), 2.11 (dd, J¼13.9, 3.4 Hz, 1H), 0.91 (s, 9H),
0.17, 0.16 (each s, 3H). Minor diastereomer: 1H NMR
(CDCl3): d 4.64 (m, 1H), 4.39 (d, J¼9.5 Hz, 1H), 4.32 (d,
J¼9.5 Hz, 1H), 3.60 (m, 1H), 3.56 (m, 1H), 2.73 (dd,
J¼18.3, 3.7 Hz, 1H), 2.56 (br d, J¼18.3 Hz, 1H), 0.89 (d,
J¼1.5 Hz, 9H), 0.14, 0.12 (each s, 3H). Anal. calcd for
C14H22O6Si: C, 53.48; H, 7.05. Found for diastereomeric
mixture: C, 53.52; H, 7.08.
4. (a) Sakamura, S.; Ito, J.; Sakai, R. Agric. Biol. Chem. 1970, 34,
153–155. (b) Sakamura, S.; Ito, J.; Sakai, R. Agric. Biol.
Chem. 1971, 35, 105–110.
5. (a) Ichihara, A.; Oda, K.; Sakamura, S. Agric. Biol. Chem.
1971, 35, 445–446. (b) Ichihara, A.; Oda, K.; Sakamura, S.
Tetrahedron Lett. 1972, 5105–5108. (c) Ichihara, A.; Oda, K.;
Sakamura, S. Agric. Biol. Chem. 1974, 38, 163–169.
(d) Ichihara, A.; Kimura, R.; Oda, K.; Sakamura, S.
Tetrahedron Lett. 1976, 51, 4741–4744. (e) Ichihara, A.;
Moriyasu, K.; Sakamura, S. Agric. Biol. Chem. 1978, 42,
2421–2422. (f) Ichihara, A.; Kimura, R.; Oda, K.; Moriyasu,
K.; Sakamura, S. Agric. Biol. Chem. 1982, 46, 1879–1883.
6. (a) Kamikubo, T.; Ogasawara, K. Tetrahedron Lett. 1995, 36,
1685–1688. (b) Kamikubo, T.; Hiroya, K.; Ogasawara, K.
Tetrahedron Lett. 1996, 37, 499–502.
3.1.7. (2)-Phyllostine (3). To a solution of 13 (90 mg,
0.28 mmol) in methanol (4.0 mL) was added DL-10-
camphorsulfonic acid (7.0 mg, 0.028 mmol), and the
mixture was stirred for 15 h at room temperature. The
resulting mixture was evaporated, and directly purified via
silica gel column chromatography to give a diastereomeric
mixture of alcohol (46 mg, 82%) as colorless oil. Rf 0.33
(AcOEt); IR (film): 3418, 1800, 1732, 1637 cm21; 1H NMR
(CDCl3): d 4.62 (m, 1H), 4.50 (d, J¼9.9 Hz, 1H), 4.41 (d,
J¼9.9 Hz, 1H), 3.70 (t, J¼4.0 Hz, 1H), 3.62 (t, J¼4.0 Hz,
1H), 2.69 (dd, J¼18.7, 3.7 Hz, 1H), 2.62 (dd, J¼18.7,
2.6 Hz, 1H). Anal. calcd for C8H8O6: C, 48.01; H, 4.03.
Found: C, 48.05; H, 4.11.
7. (a) Barros, M. T.; Maycock, C. D.; Ventura, M. R.
Tetrahedron 1999, 55, 3233–3244. (b) Barros, M. T.;
Maycock, C. D.; Ventura, M. R. Chem. Eur. J. 2000, 6,
3991–3996.
8. Liu, Z.; Li, H.; Chen, S. Huaxue Xuebao 1997, 55, 611–616.
9. Tachihara, T.; Kitahara, T. Tetrahedron 2003, 59, 1773–1780.
10. (a) Okamura, H.; Iwagawa, T.; Nakatani, M. Tetrahedron Lett.
1995, 36, 5939–5942. (b) Okamura, H.; Morishige, K.;
Iwagawa, T.; Nakatani, M. Tetrahedron Lett. 1998, 39,
1211–1214. (c) Shimizu, H.; Okamura, H.; Iwagawa, T.;
Nakatani, M. Tetrahedron 2001, 57, 1903–1908. (d) Shimizu,
H.; Okamura, H.; Yamashita, N.; Iwagawa, T.; Nakatani, M.
Tetrahedron Lett. 2001, 42, 8649–8651.
To a solution of the resulting alcohol (10 mg, 0.052 mmol)
in acetone (520 mL) containing in a round-bottomed flask in
an ice bath was added Jones reagent (2.0 M CrO3 in aq.
H2SO4, 31 mL, 0.062 mmol), and the mixture was stirred for
2.5 h in the ice bath. The mixture was poured onto aq.
saturated solution of NaHCO3 (10 mL) and extracted three
times with ethyl acetate (10 mL). The combined organic
layer was washed with brine, and dried over MgSO4. Upon
filtration, the mixture was evaporated under reduced
pressure. Purification of the residue via column chromato-
graphy provided (2)-phyllostine (3) (6.0 mg, 76%) as a
yellowish oil:16 Rf 0.50 (hexane/ethyl acetate, 3:7);
[a]2D8¼2120 (c 0.28, EtOH); [lit.: [a]3D1¼2100.4 (c 0.6,
EtOH);6b [a]2D6¼2118.7 (c 0.05, EtOH);6a [a]2D0¼2105.6 (c
11. Afarinkia, K.; Vinader, V.; Nelson, T. D.; Posner, G. H.
Tetrahedron 1992, 48, 9111–9171.
12. A similar base-catalyzed DA reaction was reported for the
reaction of anthrone with electron deficient dienophiles
(a) Koerner, M.; Rickborn, B. J. Org. Chem. 1989, 54, 6–7.
(b) Koerner, M.; Rickborn, B. J. Org. Chem. 1990, 55,
2662–2672. (c) Riant, O.; Kagan, H. B.; Ricard, L.
Tetrahedron 1994, 50, 4543–4554.
1.0, EtOH)];4 IR (film): 3400, 1686 cm21 1H NMR
;
(CDCl3): d 6.69 (dt, J¼4.0, 2.0 Hz, 1H), 4.58 (ddd,
J¼17.4, 5.8, 2.0 Hz, 1H), 4.40 (ddd, J¼17.4, 5.8, 2.0 Hz,
1H), 3.82–3.85 (m, 2H), 1.98 (t, J¼5.8 Hz, 1H); 13C NMR
(CDCl3):17 d 191.5, 190.6, 147.6, 130.8, 59.2, 54.0. Anal.
13. Yang, C. N.; Finnegan, R. A. J. Am. Chem. Soc. 1958, 80,
5845–5848.
14. (a) Birch, A. J.; Subba Rao, G. S. R. Tetrahedron Lett. 1968,
3797–3798. (b) Andrieux, J.; Barton, D. H. R.; Patin, H.