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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
La activación del peróxido de hidrógeno y el dioxígeno por complejos dinucleares de cobre en solución acuosa:
Qing Zhu1, Yuxiang Lian, Sunita Thyagarajan
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|April 25, 2008
Resumen
Los complejos dinucleares de cobre (CuII2Nn) dividen selectivamente el ADN mediante la generación de radicales basados en hidroxilo o ligando. Esto ocurre a través de un mecanismo de transferencia de electrones intramolecular, no una reacción directa con un intermediario metal-peróxido.
Área de la Ciencia:
- Química bioorgánica Química bioorgánica.
- Mecanismos de escisión del ADN.
- Química Radical La Química Radical es una ciencia
Sus antecedentes:
- Los complejos dinucleares de cobre (CuII2Nn) muestran actividad de escisión selectiva del ADN.
- La reactividad depende de la estructura compleja (dinuclear vs. mononuclear) y las condiciones de reacción (tiol/O2 o H2O2).
Objetivo del estudio:
- Para dilucidar el mecanismo de la escisión del ADN mediada por complejos CuII2Nn.
- Para identificar las especies reactivas responsables del daño del ADN.
Principales métodos:
- Estudios espectroscópicos para caracterizar los intermediarios de reacción.
- Análisis cinético para determinar las vías de reacción.
- Investigación de la reactividad intermedia con donantes de electrones.
Principales resultados:
- Se genera un producto intermedio a partir de complejos CuII2Nn en condiciones de reacción.
- Este intermedio se descompone para producir radicales hidroxilo (OH) y productos de degradación de ligando.
- La desintegración del intermedio implica la transferencia intramolecular de electrones, generando radicales OH y radicales basados en ligandos.
- La escisión del ADN se atribuye a estos radicales, no a una interacción directa entre metal y peróxido.
Conclusiones:
- La escisión del ADN por complejos CuII2Nn está mediada por radicales OH o radicales basados en ligandos.
- El mecanismo implica la transferencia intramolecular de electrones desde el ligando al centro peroxo metálico.
- Los complejos mononucleares y CuII2N3 no exhiben esta reactividad selectiva.
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