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Estabilización de 310-hélices en macrociclos utilizando la metodología del rotor dominante
Martynas J Širvinskas1, George J Saunders1, Monica Mitrache1
1Davenport Research Laboratories, University of Toronto, 80 St. George St., Toronto, Ontario M5S 3H6, Canada.
Journal of the American Chemical Society
|August 19, 2024
Resumen
Los rotores atropisoméricos estabilizan raras 3 subhélices en macrociclos, un estado normalmente metastable. Estas estructuras helicoidales permanecen estables incluso después de un calentamiento prolongado y pueden enriquecerse selectivamente.
Área de la Ciencia:
- Síntesis química y biología estructural
- Química supramolecular y ciencia de los péptidos
Sus antecedentes:
- La estabilización de motivos estructurales biológicamente relevantes es un desafío importante en la química.
- Las 310-hélices raras son típicamente metastables y difíciles de mantener en estructuras macrocíclicas.
Objetivo del estudio:
- Investigar la estabilización de 3 subhélices en macrociclos utilizando rotores atropisómricos dominantes.
- Explorar el potencial de estas hélices estabilizadas para aplicaciones que requieren motivos estructurales robustos.
Principales métodos:
- Síntesis de péptidos en fase sólida para la preparación del macrociclo.
- Análisis estructural extenso y simulaciones de dinámica molecular (DM) para la determinación de la estructura de la solución.
- Ensayos de estabilidad térmica para evaluar la retención de helicidad.
Principales resultados:
- Los rotores dominantes atropisoméricos estabilizaron con éxito 3 subhélices en macrociclos.
- Las simulaciones de MD proporcionaron evidencia de la formación de hélices estables 3, superando la metestabilidad habitual.
- Las 3 subhélices demostraron una notable estabilidad térmica, conservando la helicidad después de calentarse a 100 °C durante 72 horas.
- El enriquecimiento térmico de mezclas atropisoméricas brutas produjo 310-macrociclos helicoidales con alta selectividad (>20:1).
Conclusiones:
- Los rotores atropisoméricos son herramientas efectivas para estabilizar estructuras helicoidales 310 de otro modo en macrociclos.
- La estabilidad térmica demostrada y el enriquecimiento selectivo ofrecen vías prometedoras para el diseño de compuestos macrocíclicos robustos.
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