Organic Letters
Letter
M.; Eder, M.; Eisenhut, M.; Hadaschik, B. A.; Kopp-Schneider, A.;
homologues. With the implementation of this new approach
(that does not set any limits on the size of the macroring,8a
type, and position of the side chains, if compatible with BH3
and harsh acidic conditions), we believe that previously
inaccessible ligands will be easily synthesized and it will surely
increase the utilization of these macrocyclic ligands not only as
useful MRI contrast agents but also in general catalysis and
coordination chemistry, where advances have been heavily
hindered by the nature of currently accessible derivatives.
Studies on the synthesis of chiral and N-bridged macro-/
polycyclic derivatives are in progress. The results will appear in
due course.
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ASSOCIATED CONTENT
* Supporting Information
■
S
The Supporting Information is available free of charge on the
Experimental procedures, characterization data, and
HPLC chromatograms of the new compounds (PDF)
Accession Codes
tallographic data for this paper. These data can be obtained
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
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Thermodynamic and kinetic studies of lanthanide complexes of
1,4,7,10,13-pentaazacyclopentadecane-N,N′,N′′,N′′′,N′′′′-pentaacetic
a c i d a n d 1 , 4 , 7 , 1 0 , 1 3 , 1 6 - h e x a a z a c y c l o o c t a d e c a n e -
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AUTHOR INFORMATION
Corresponding Authors
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ORCID
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Bacsa, J.; Scarborough, C. C. Synthesis of Previously Inaccessible
Derivatives of 1,4,7-Tri-R-1,4,7-Triazacyclononane, Including Chiral
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Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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Financial support from the University of Salerno (FARB), and
from POR CAMPANIA FESR 2014-2020 O.S.1.1.
CUPB83D18000150007 “Un approccio Integrato al Telecare
in Ambito Oncologico”. We thank Ms Oliwia Ida Rebacz,
University of Salerno, for experimental work; Dr. Patrizia
Iannece, University of Salerno, for HR-MS and elemental
analysis; and Dr. Patrizia Oliva, University of Salerno, for
NMR spectra.
(6) This approach was mentioned in the review: Culf, A. S. Peptoids
as tools and sensors. Biopolymers 2019, 110, No. e23285.
(7) Zuckermann, R. N.; Kerr, J. M.; Kent, S. B. H.; Moos, W. H.
Efficient Method for the Preparation of Peptoids [Oligo(N-
Substituted Glycines)] by Submonomer Solid-Phase Synthesis. J.
Am. Chem. Soc. 1992, 114, 10646−10647.
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Napolitano, A.; Pizza, C.; Tedesco, C.; Flot, D.; De Riccardis, F.
Synthesis, Structures, and Properties of Nine-, Twelve-, and Eighteen-
Membered N-Benzyloxyethyl Cyclic α-Peptoids. Chem. Commun.
2008, 3927−3929. (c) D’Amato, A.; Schettini, R.; Della Sala, G.;
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