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Cinética de la solución de la apertura del anillo A CC-1065: efectos sustitutivos y catálisis ácido/base general
Daniel V LaBarbera1, Edward B Skibo
1Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA.
Journal of the American Chemical Society
|March 16, 2006
Resumen
El anillo CC 1065 A es un anillo.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
- Biología Química Biología química.
Sus antecedentes:
- CC 1065 es un potente agente alquilador del ADN.
- El anillo A de CC 1065 es crucial para su actividad de unión al ADN y alquilación.
- Comprender la reactividad del anillo A es clave para diseñar nuevos análogos.
Objetivo del estudio:
- Para investigar la reactividad dependiente del pH de los derivados de anillo A CC 1065 2-sustituidos.
- Para determinar el mecanismo de la apertura del anillo de ciclopropilo y la captura de nucleófilos.
- Para evaluar la influencia de los 2-sustitutos en estas reacciones.
Principales métodos:
- Se realizaron estudios de la tasa de pH de los derivados de anillo A CC 1065 2-sustituidos en un rango de pH de 0 a 5.
- Analizó la cinética de la apertura del anillo de ciclopropilo y la captura de nucleófilos (cloruro).
- Utilizó métodos computacionales para comprender los efectos electrónicos de los sustituyentes.
Principales resultados:
- Se ha demostrado la captura reversible catalizada por ácido/base general de nucleófilos de cloruro por el grupo ciclopropilo por encima de pH 4.
- Se demostró que el 2-sustituto tiene un impacto mínimo en el pKa de carbonilo del anillo A y en las tasas de captura de nucleófilos.
- Los estudios computacionales indicaron que el anillo de pirrolo fundido es la fuente primaria de densidad de electrones para el oxígeno carbonilo.
Conclusiones:
- La alquilación general catalizada por ácido del ADN por el anillo A CC 1065 es factible cerca de un pH neutro.
- Los efectos electrónicos del 2-sustituto sobre la reactividad del grupo ciclopropilo del anillo A son limitados.
- El anillo pirroló fundido influye significativamente en las propiedades electrónicas del anillo A.
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