학술논문
Conformational studies on a medium size cyclopseudopeptide containing the oxazolidin-2-one moiety Conformational studies on a medium size cyclopseudopeptide containing the oxazolidin-2-one moiety.
Document Type
Article
Source
Subject
*OXAZOLIDINES
*CHEMICAL synthesis
*CONFORMATIONAL analysis
*PEPTIDE synthesis
*RING formation (Chemistry)
*SOLUTION (Chemistry)
*NUCLEAR magnetic resonance spectroscopy
*DRUG delivery systems
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Language
ISSN
0894-3230
Abstract
An efficient synthesis of a 24 pseudopeptide membered ring in solution is reported in good yield. The cycle contains four units, all formed by an α-amino acid (Xaa) and a 4-carboxy-5-methyl-oxazolidin-2-one group (4-carboxy-5-methyl-oxazolidin-2-one = Oxd) in the same configuration ( l or d). In the final sequence, the four ll or dd units are alternated so that, after cyclization, cyclo-( l-Xaa- l-Oxd- d-Xaa- d-Oxd- l-Xaa- l-Oxd- d-Xaa- d-Oxd) is formed. The conformational analysis of this compound has been performed by means of infrared and 1 H NMR spectroscopy and shows that the CHα hydrogens of the α-amino acids retain the very deshielded chemical shifts recorded in the spectra of the free precursors. Furthermore, the NH hydrogen have a weak tendency to form cross peaks, thus suggesting that the cycle lies in a large circle able to host small molecules, thus this compound is a promising candidate for drug delivery studies. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]