References
- (a) A. Ichihara, K. Shiraishi, H. Sato, S. Sakamura, K. Nishiyama, R. Sakai, A. Furusaki, and T. Matsumoto, J. Am. Chem. Soc., 99, 636–637 (1977); (b) A. Ichihara, K. Shiraishi, S. Sakamura, K. Nishiyama, and R. Sakai, Tetrahedron Lett., 1977, 269–272; (c) A. Ichihara, K. Shiraishi, S. Sakamura, A. Furusaki, N. Hashimoto, and T. Matsumoto, Tetrahedron Lett., 1979, 365–368.
- (a) F. Greulich, T. Yoshihara, and A. Ichihara, J. Plant Physiol., 147, 359–366 (1995); (b) T. Krumm and W. Boland, Molecules, 1, 23–26 (1996); (c) Y. Koda, K. Takahashi, Y. Kikuta, F. Greulich, H. Toshima, and A. Ichihara, Phytochemistry, 41, 93–96 (1996) and references cited therein.
- (a) M. Nakayama and S. Ohira, Agric. Biol. Chem., 47, 1689–1690 (1983); (b) G. Mehta and M. Pravean, J. Chem. Soc., Chem. Commun., 1993, 1573–1575 and references cited therein; (c) S. Holder and S. Blechert, Synlett, 1996, 505–506.
- S. Nara, H. Toshima, and A. Ichihara, Tetrahedron Lett., 37, 6745–6748 (1996).
- (a) D. R. Deardorff, A. J. Matthews, D. S. McMeekin, and C. L. Craney, Tetrahedron Lett., 27, 1255–1256 (1986); (b) A. G. Myers, M. Hammond, and Y. Wu, Tetrahedron Lett., 37, 3083–3086 (1986) and references cited therein.
- Satisfactory spectroscopic data were obtained for all the new compounds.
- H. Grebe, A. Lange, H. Riechers, K. Kieslich, W. Viergutz, P. Washausen, and E. Winterfelt, J. Chem. Soc., Perkin Trans. 1, 1991, 2651–2655.
- Column, Chiralcel OC® (φ4.6 × 250 mm); eluent, hexane/2-propanol (96/4); flow rate, 0.3 ml/min; detection, UV 220 nm; retention times: 8, 36 min; enantiomer of 8, 40 min.
- The same column and conditions as those in ref. 8 were used; detection by UV at 240 nm retention times: 10a, 64 min; 10b, 59 min.
- Although the first reported mp of natural (+)-2 is described as 125–126°C in ref. 1a, the corrected mp value is described as 141–142°C in the thesis of Dr. K. Shiraishi (Hokkaido University, 1978). Furthermore, Prof. M. Nakayama has reported mp 142–143°C for his synthetic (+)-2 and our natural sample in ref. 3a.
- H. Toshima and A. Ichihara, Biosci. Biotech. Biochem., 59, 495–500 (1995).
- Although the mp of natural (+)-1 is described as 151–153°C in ref. la, 161–163°C is the corrected value in the thesis of Dr. K. Shiraishi. Since we have no natural sample at the present time, the specific rotations, which may be influenced by the temperature, cannot be compared directly.