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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Ciclo[n]pirroles: tamaño y sitio específico de unión a los cuadruplexos G
Erin Shammel Baker1, Jeong Tae Lee, Jonathan L Sessler
1Department of Chemistry and Biochemistry, University of California, Santa Barbara, 93106-9510, USA.
Journal of the American Chemical Society
|February 24, 2006
Resumen
Los ciclo[n]pirroles diprotonados se unen a las secuencias teloméricas humanas. Los ciclo[n]pirroles más pequeños se unen más fuertemente, con el apilamiento externo como el modo dominante, lo que sugiere potencial para el diseño de fármacos contra el cáncer.
Área de la Ciencia:
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
- Química biofísica y bioquímica.
- Diseño de drogas de diseño de drogas.
Sus antecedentes:
- La estabilización de las estructuras G-cuadruplex es una estrategia clave para el desarrollo de fármacos contra el cáncer.
- La telomestatina, un producto natural, estabiliza las G-cuadruplexas e inhibe la telomerasa.
- Los ciclo[n]pirroles son análogos expandidos de la porfirina estructuralmente similares a la telomestatina.
Objetivo del estudio:
- Para investigar el potencial de los ciclo[n]pirroles diprotonados como estabilizadores G-cuadruplex.
- Para determinar la afinidad y el modo de unión de los ciclo[n]pirroles con la secuencia de repetición del telómero humano.
Principales métodos:
- Se utilizó la espectrometría de masas de ionización nano-electrospray (Nano-ESI-MS) para evaluar la unión.
- Se utiliza la espectrometría de movilidad iónica para medir las secciones transversales de colisión de complejos.
- Realizó cálculos de dinámica molecular para racionalizar las observaciones experimentales.
Principales resultados:
- Los ciclo[n]pirroles más pequeños exhibieron una unión más fuerte a la secuencia d(T(2)AG(3))(4).
- El ciclo[6]pirrol mostró una mayor unión en comparación con la octaetilporfirina debido a su carga.
- Los datos de movilidad iónica indicaron el apilamiento externo como el modo de unión predominante.
Conclusiones:
- Los ciclo[n]pirroles diprotonados interactúan con los G-cuadruplexos principalmente a través del apilamiento externo.
- La fuerza de unión está influenciada por el tamaño y la carga de las moléculas de ciclo[n]pirrol.
- Estos hallazgos apoyan el potencial de los ciclo[n]pirroles en el diseño de fármacos anticancerígenos dirigidos a la telomerasa.
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