Organic Letters
Letter
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(13) Ren, H.; Wulff, W. D. Org. Lett. 2013, 15, 242.
(14) For a recent solution to this problem, see: Lewis, R. S.; Garza,
C. J.; Dang, A. T.; Pedro, T. K. A.; Chain, W. J. Org. Lett. 2015, 17,
2278.
(15) The use of less hindered bases, such as LDA, gave significantly
lower yields in the o-quinone methide coupling reactions.
(16) (a) Ireland, R. E.; Wipf, P.; Armstrong, J. D. J. Org. Chem.
1991, 56, 650. (b) Xie, L.; Saunders, W. H. J. Am. Chem. Soc. 1991,
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(17) For the observation of a similar hydrogen-bond-directed
spiroketalization in the synthesis of virgatolide B, see: (a) Hume, P.
A.; Furkert, D. P.; Brimble, M. A. Org. Lett. 2013, 15, 4588.
(b) Hume, P. A.; Furkert, D. P.; Brimble, M. A. J. Org. Chem. 2014,
79, 5269. Also see ref 7.
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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S
Experimental procedures and full characterization data
for all new compounds (PDF)
AUTHOR INFORMATION
Corresponding Author
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Notes
(18) For the isolation of the virgatolides, see: Li, J.; Li, L.; Si, Y.;
Jiang, X.; Guo, L.; Che, Y. Org. Lett. 2011, 13, 2670. For the
synthesis of virgatolide A, see ref 16.
(19) For the isolation of the chaetoquadrins, see: (a) Fujimoto, H.;
Nozawa, M.; Okuyama, E.; Ishibashi, M. Chem. Pharm. Bull. 2002,
50, 330. (b) Fujimoto, H.; Nozawa, M.; Okuyama, E.; Ishibashi, M.
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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We thank the Australian Research Council for financial
support in the form of a Discovery Early Career Researcher
Award (DE130100689) to J.H.G.
Chem. Pharm. Bull. 2003, 51, 247.
For the synthesis of
chaetoquadrins A−C, see: (c) Kim, U. B.; Furkert, D. P.; Brimble,
M. A. Org. Lett. 2013, 15, 658.
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