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2005, 16, 225.
3. Combretastatin D-1, 2: G. R. Pettit, S. B. Singh, and M. L. Niven, J. Am. Chem. Soc., 1988, 110,
8539; G. R. Pettit, S. B. Singh, and M. L. Niven, J. Org. Chem., 1990, 55, 2797. Combretastatin
D-3, 4: N. Vongvanich, P. Kittakoop, P. Charoenchai, S. Intamas, K. Danwisetkanjana, and Y.
Thebraranonth, Planta Med., 2005, 71, 191.
4. R. Frlan and D. Kikelj, Synthesis, 2006, 2271.
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6. S. Yamamura and S. Nishiyama, ‘Studies in Natural Products Chemistry: Biomimetic Synthesis of
Macrocyclic Oligopeptides Having Isodityrosine and Related Units,’ Vol. 10F, ed. by
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7. Unpublished result.
8. G. W. Perold, A. J. Hodgkinson, and A. S. Howard, J. Chem. Soc., Perkin Trans. 1, 1972, 2450.
This compound was prepared by essentially the same procedure as previously reported; see, F. Doi,
T. Ohara, T. Ogamino, K. Higashinakasu, K. Hasegawa, and S. Nishiyama, Bull. Chem. Soc. Jpn.,
2004, 77, 2257.
9. Usually halogen substituents at the ortho position of phenol groups modulate their oxidation
potential and reaction pathway to provide clean and efficient oxidation reactions, see ref. 6.
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Commun., 1996, 26, 1887.
1
12. IR (film) 1504, 1518, 1597, 1730, 2925, 3422 cm-1; H-NMR δ 2.10 (2H, m), 2.25 (2H, t, J = 5.2
Hz), 2.82 (4H, m), 4.06 (2H, t, J = 4.8 Hz), 5.29 (1H, d, J = 2 Hz), 5.53 (1H, s), 6.60 (1H, d, J = 6
13
Hz), 6.93 (1H, d, J = 8 Hz), 7.01 (2H, d, J = 8.4 Hz), 7.30 (2H, d, J = 8.8 Hz); C-NMR δ 27.1,
28.7, 32.8, 34.0, 63.9, 112.5, 114.9, 121.4, 123.5, 131.0, 132.6, 137.8, 142.4, 149.0, 154.1, 173.8.
HREIMS found m/z 298.1199, calcd for C18H18O4: M, 298.1205.
13. The inhibition of human HT29 colon carcinoma cells was measured by MTT assay. The cells were
seeded at 2 x 104 cells well in 96-well plates. After overnight incubation, cells were treated for 48
h with increasing concentrations of compound (up to 30 µg/mL). Then MTT (5 mg/mL in PBS)