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Metátesis de olefinas Z-Selectivas en péptidos: investigación de la influencia de la cadena lateral, preorganización
Shane L Mangold1, Daniel J O'Leary, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories for Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|August 8, 2014
Resumen
Nuevos catalizadores de rutenio permiten un control preciso de la geometría Z-selectiva de las olefinas en los péptidos. Esta investigación explora los factores que influyen en la actividad del catalizador y la selectividad para aplicaciones sintéticas más amplias.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- Química del péptido Química del péptido
Sus antecedentes:
- La metátesis de olefinas es valiosa para modificar moléculas biológicamente activas.
- El control de la geometría de las olefinas del producto, en particular la selectividad Z, sigue siendo un desafío importante.
- Los catalizadores de rutenio ciclometalizados ofrecen un mejor estereocontrol, pero su aplicación a los péptidos está poco explorada.
Objetivo del estudio:
- Para evaluar los factores que influyen en la metátesis Z-selectiva de olefinas en sustratos de péptidos.
- Explorar el alcance y las limitaciones de los catalizadores de rutenio ciclometalizado en la modificación de péptidos.
- Establecer criterios para la alta conversión y la selectividad Z en la metátesis de péptidos.
Principales métodos:
- Investigó la homodimerización, la metátesis cruzada y la metátesis de cierre de anillo en péptidos.
- Evaluó el impacto de los estéricos, la identidad de la cadena lateral de aminoácidos y la estructura secundaria de péptidos.
- Se utilizaron catalizadores de rutenio ciclometalizado para la metátesis de olefinas Z-selectivas.
Principales resultados:
- La identidad de la cadena lateral de aminoácidos y la estructura de las olefinas afectan significativamente la actividad del catalizador y la selectividad Z.
- La estructura secundaria del péptido y los factores estéricos juegan un papel crucial en los resultados de la reacción.
- Se ha demostrado el éxito de la metátesis Z-selectiva en diversos sustratos péptidos.
Conclusiones:
- Criterios desarrollados para lograr una alta conversión y Z-selectividad en la metátesis de péptidos.
- Amplió la utilidad de la metátesis de olefinas Z-selectivas a sistemas complejos de péptidos.
- Proporcionó ideas para aplicaciones generales de la metátesis estereoselectiva de olefinas en la síntesis.
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