Organic Letters
Letter
making available the necessary quantities of 1 to hopefully
realize the full potential of (−)-rasfonin (1) as a novel cancer
therapeutic agent.
Scheme 3. Completion of Pyranone 2
ASSOCIATED CONTENT
* Supporting Information
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S
The Supporting Information is available free of charge on the
Experimental procedures (PDF)
AUTHOR INFORMATION
■
Corresponding Author
ORCID
acid 3 with alcohol 2 proceeded without remark, and a final
treatment with HF (48% in water) in acetonitrile8 afforded
(−)-rasfonin (1) i whose spectroscopic data were in complete
agreement with those of authentic (−)-rasfonin and our
previously prepared synthetic sample in nearly quantittive
yield (Scheme 4).1
Notes
The authors declare the following competing financial
interest(s): (−)-Rasfonin generated via the outlined synthesis
is currently undergoing biological profiling at the Max-Planck
Institute of Molecular Physiology in Dortmund Germany by
Dr. Herbert Waldmann and his group.
Scheme 4. Completion of (−)-Rasfonin (1)
ACKNOWLEDGMENTS
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The authors would like to thank Dr. Douglas Tusch, Dr.
Daniel Austin, and Ali Lambright of the Department of
Chemistry at the University of Rochester for their initial efforts
toward the synthesis of the northern hemisphere.
REFERENCES
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