Accessing Improbable Foldamer Shapes with Strained Macrocycles.
Chemistry
; 27(43): 11205-11215, 2021 Aug 02.
Article
em En
| MEDLINE
| ID: mdl-33905165
ABSTRACT
The alkylation of some secondary amide functions with a dimethoxybenzyl (DMB) group in oligomers of 8-amino-2-quinolinecarboxylic acid destabilizes the otherwise favored helical conformations, and allows for cyclization to take place. A cyclic hexamer and a cyclic heptamer were produced in this manner. After DMB removal, X-ray crystallography and NMR show that the macrocycles adopt strained conformations that would be improbable in noncyclic species. The high helix folding propensity of the main chain is partly expressed in these conformations, but it remains frustrated by macrocyclization. Despite being homomeric, the macrocycles possess inequivalent monomer units. Experimental and computational studies highlight specific fluxional pathways within these structures. Extensive simulated annealing molecular dynamics allow for the prediction of the conformations for larger macrocycles with up to sixteen monomers.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Amidas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Chemistry
Assunto da revista:
QUIMICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Japão