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Acknowledgements
This research was financially supported by the Funding Program for a Grant-in-Aid for
Scientific Research (A) (JSPS Grant no. 26253003) to M.I., and a Grant-in-Aid for Scientific
Research (C) (JSPS Grant no. 16K08156) to M.N. A Fellowship from JSPS to K.M. is
gratefully acknowledged. We thank D. Kamimura (Kaken Pharmaceutical) for conducting
the preliminary experiments for dimerization reactions. This paper is dedicated to
Professor Samuel J. Danishefsky on the occasion of his 80th birthday.
Author contributions
K.M., M.N. and M.I. conceived and designed the study. K.M. and M.N. performed the
syntheses and M.N. and M.I. co-wrote the paper.
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Additional information
Supplementary information and chemical compound information are available in the
to M.I.
Competing financial interests
The authors declare no competing financial interests.
6
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