On the conformational search of a ßCD dendritic derivative: NMR and theoretical calculations working together reveal a donut-like amphiphilic structure
Por:
López-Méndez L.J., Rojas-Aguirre, Yareli, Vazquez-Lima, Hugo, Cassani, Julia, Enriquez, Raul G., Rojo-Dominguez, Arturo, Guadarrama, Patricia
Publicada:
1 ene 2020
Resumen:
The conformational behavior of host molecular systems is intimately related to their performance, both as molecular containers and as interfaces in biological environments. Thus, it is of great importance to carry out rational analyses to understand this behavior. In the present study we established a systematic feedback methodology by correlating 1D and 2D NMR data (1H and NOESY) and theoretical calculations (semiempirical PM6, two-layer method QM/QM and Molecular Dynamics) comprehensively, to elucidate the conformation of a large, flexible poly(ester) dendritic ß-cyclodextrin derivative (ßCD[G2]-OH). Three models (A: donut-like, B: ball and C: vase) were constructed as suitable candidates to preserve the C7 symmetry observed in the 1H NMR spectrum. The electronic relative energies, complemented with the experimental chemical shifts provided the initial criterion to select Model A as the most likely conformation. The selection was validated through NOESY NMR experiments and calculated chemical shifts by QM/QM. Additionally, the dynamic behavior was explored computationally to confirm that the most stable and persistent conformation for ßCD[G2]-OH was model A. Our methodology revealed that ßCD[G2]-OH adopts a donut-like arrangement in which hydrophobic pockets are formed and distributed throughout the structure, rendering information about its amphiphilic character, making this molecule a very attractive host. © 2019 Elsevier B.V.
Filiaciones:
López-Méndez L.J.:
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico
Rojas-Aguirre, Yareli:
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
Vazquez-Lima, Hugo:
Centro de Química, Instituto de Ciencias, Universidad Autónoma de Puebla, Edif. IC9, CU, San Manuel, Puebla, Pue 72570, Mexico
Univ Autonoma Puebla, Ctr Quim, Inst Ciencias, CU, Edif IC9, Puebla 72570, Pue, Mexico
Cassani, Julia:
Universidad Autónoma Metropolitana-Xochimilco. Mexico City04960, Mexico
Univ Autonoma Metropolitana Xochimilco, Mexico City 04960, DF, Mexico
Enriquez, Raul G.:
Instituto de Química, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Inst Quim, Mexico City 04510, DF, Mexico
Rojo-Dominguez, Arturo:
Departamento de Química, Universidad Autónoma Metropolitana. Unidad Cuajimalpa, Mexico City, 05370, Mexico
Univ Autonoma Metropolitana, Dept Quim, Unidad Cuajimalpa, Mexico City 05370, DF, Mexico
Guadarrama, Patricia:
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico
Univ Nacl Autonoma Mexico, Inst Invest Mat, Mexico City 04510, DF, Mexico
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