Synthesis of phototrappable shape-shifting molecules for adaptive guest binding.
J Am Chem Soc
; 132(44): 15790-9, 2010 Nov 10.
Article
em En
| MEDLINE
| ID: mdl-20945902
ABSTRACT
We have designed and synthesized oligosubstituted bullvalenes 1 and 2 as adaptive molecules that can change their shapes in order to bind tightly to a suitable guest. By incorporation of a photolabile o-nitroveratryloxycarbonate (NVOC) group into bullvalenes 1 and 2, tightly binding species can be selectively isolated from a population of hundreds of interconverting structural isomers. Spontaneous strain-assisted Cope rearrangements allow these shape-shifting molecules to exist in a dynamic equilibrium of configurationally distinct valence isomers, as revealed by dynamic NMR and HPLC studies. When NVOC bullvalenes 1 and 2 were exposed to UV light, the cleavage of the NVOC group resulted in a mixture of static isomers of the corresponding bullvalone. Binding studies of NVOC bisporphyrin bullvalene 1 demonstrated that the dynamic isomeric equilibrium shifted in the presence of C(60), favoring configurations with more favorable binding affinities. Irradiation of a mixture of 1 and C(60) with UV light and isolation of the major static isomer yielded an isomer of bisporphyrin bullvalone with a binding affinity for C(60) that was â¼2 times larger than that of the nonadapted isomer bisporphyrin bullvalone 41.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligonucleotídeos
/
Porfirinas
/
Luz
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article