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This method allows the introduction of the sugar moieties as
the final step under mild conditions, paving the way for more
complex and less stable sugars. All of the glucosylated and non-
glucosylated copoly(L-glutamate)s adopted a random-coil
conformation in neutral and basic media and an α-helical
conformation in acidic media, with the helical content
depending on the number and configuration of allyl-/
propargylglycine units. The glucosylated copolypeptides
exceeded the helical stability of unfunctionalized poly(L-
glutamate)s and were soluble down to pH 3.5. A maximum
helicity of ∼76% was reached prior to precipitation. Turbidity
assays proved the selective binding of the glucocopolypeptides
to the plant lectin ConA.
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ASSOCIATED CONTENT
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S
* Supporting Information
1
Experimental procedures; H and 13C NMR data for all NCA
monomers (1 and 2a−c); and 1H NMR, CD, SEC, and
analytical ultracentrifugation data for copolypeptides 4a−c and
6a−c. This material is available free of charge via the Internet at
AUTHOR INFORMATION
Corresponding Author
■
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
The authors thank Joshua W. Robinson, Felix Wojcik, Nora
Fiedler, Jessica Brandt, Marlies Grawert, Antje Volkel, and Olaf
Niemeyer for their valuable contributions to this work. This
work was supported by the IUPAC Transnational Pilot Call in
Polymer Chemistry and the German Research Foundation
(DFG) (SCHL 566/5-1).
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