Journal of Natural Products
Article
DMF (3 min × 5). The washed Lantern was immediately used for the
next reaction. To a suspension of Lantern, Fmoc-D-Leu-OH (0.100
M), and HOBt (0.150 M) in DMF (1.00 mL/Lantern) was added
DIC (0.100 M), and the mixture was shaken at rt. After being shaken
for 12 h, the reaction mixture was filtered and the Lantern was washed
with DMF (3 min × 3), THF/H2O (3:1) (3 min × 3), MeOH (3 min
× 2), and CH2Cl2 (3 min × 2). The washed Lantern was dried in
vacuo to afford polymer-supported hexapeptide 11.
Deprotection of the Fmoc Group and Cleavage from the
Polymer Support. The N-Fmoc-protected hexapeptide-supported
Lantern 11 was treated with a solution of 20% piperidine in DMF at rt.
After being shaken for 1 h, the reaction mixture was filtered and the
Lantern was washed with DMF (3 min × 5) and CH2Cl2 (3 min × 2).
The washed Lantern was dried in vacuo. The dried Lantern was
immediately treated with 30% HFIP/CH2Cl2 at rt. After being shaken
for 1 h, the reaction mixture was filtered and the Lantern was washed
with CH2Cl2 (3 min × 3). The combined filtrate was concentrated in
vacuo, and the crude cyclization precursor 12 was used for the next
reaction after it was passed through a short pad of silica gel.
REFERENCES
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́
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D
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1
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ASSOCIATED CONTENT
* Supporting Information
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S
The Supporting Information is available free of charge on the
1
Copies of H and 13C NMR spectra for 5 (PDF)
AUTHOR INFORMATION
Corresponding Authors
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Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work was supported in part by Grants-in-Aid for Scientific
Research (B) (No. 26282208 for T.D.) and for Young
Scientists (B) (No. 26850068 for Y.M.), Excellent Graduate
Schools, and Platform for Drug Discovery, Informatics, and
Structural Life Science from MEXT, Japan.
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J. Nat. Prod. XXXX, XXX, XXX−XXX