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Water-Soluble Chiral Cyclic Peptoids and Their Sodium and Gadolinium Complexes: Study of Conformational and Relaxometric Properties.

ABSTRACT: Cyclic peptoids are macrocyclic oligomers of N-substituted glycines with specific folding abilities and excellent metal binding properties. In this work, we show how strategic positioning of chiral (S)- and (R)-(1-carboxyethyl)glycine units influences the conformational stability of water-soluble macrocyclic peptoids as sodium complexes. The reported results are based on nuclear magnetic resonance spectroscopy, extensive computational studies, and X-ray diffraction analysis using single crystals grown from aqueous solutions. The studies include ¹H relaxometric investigations of hexameric cyclic peptoids in the presence of the Gd³⁺ ion to assess their thermodynamic stabilities and relaxivities.

SUBMITTER: D'Amato A

PROVIDER: S-EPMC10242754 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Water-Soluble Chiral Cyclic Peptoids and Their Sodium and Gadolinium Complexes: Study of Conformational and Relaxometric Properties.

D'Amato Assunta A Jiang Linhai L Della Sala Giorgio G Kirshenbaum Kent K Costabile Chiara C Furlan Chiara C Gianolio Eliana E Izzo Irene I De Riccardis Francesco F

The Journal of organic chemistry 20230508 11

Cyclic peptoids are macrocyclic oligomers of N-substituted glycines with specific folding abilities and excellent metal binding properties. In this work, we show how strategic positioning of chiral (<i>S</i>)- and (<i>R</i>)-(1-carboxyethyl)glycine units influences the conformational stability of water-soluble macrocyclic peptoids as sodium complexes. The reported results are based on nuclear magnetic resonance spectroscopy, extensive computational studies, and X-ray diffraction analysis using s ...[more]

PMID: 37155983

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