Organic Letters
Letter
(13) Kakinoki, S.; Hirano, Y.; Oka, M. Pept. Sci. 2004, 457.
eight short oligomers containing both L-Pro and the L-Oxd
moieties. We have shown that short oligomers of L-Pro fold in a
PPI helix only in diluted solution because, if the concentration
rises, PPII helices are stabilized by the presence of aggregates that
are stable even after several days and may be detected by dynamic
light scattering analysis. Moreover, we have demonstrated that
the L-Oxd moiety always inhibits the formation of PPI helices and
strongly favors the formation of stable PPII helices.
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ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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(17) (a) Bernardi, F.; Garavelli, M.; Scatizzi, M.; Tomasini, C.; Trigari,
V.; Crisma, M.; Formaggio, F.; Peggion, C.; Toniolo, C. Chem. - Eur. J.
2002, 8, 2516. (b) Lucarini, S.; Tomasini, C. J. Org. Chem. 2001, 66, 727.
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Cornia, A.; Calvaresi, M.; Zerbetto, F.; Tomasini, C. J. Org. Chem. 2014,
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Synthetic procedure and characterization of compounds
1−8. Copy of the 1H and 13C NMR spectra of compounds
1−8. ECD spectra of compounds 1−8 in n-propanol at 3,
0.3, and 0.03 mM concentration. Size distribution by
volume (DLS analysis) of the particles from a solution of
molecules 2 and 8 in n-propanol at 3 and 0.3 mM
AUTHOR INFORMATION
Corresponding Author
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*Phone: +39-0512099486. Fax: +39-0512099486. E-mail:
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
We thank Prof. Giovanna Longhi (Dipartimento di Medicina
Molecolare e Traslazionale - Universita
helpful discussions on the ECD spectra. C.T. thanks “Ministero
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degli Studi di Brescia) for
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dell’Istruzione dell’Universita e della Ricerca” (MIUR) (program
PRIN 2010NRREPL_009).
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