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Síntesis catalítica enantioselectiva de las piridil sulfoximinas
1Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States.
Journal of the American Chemical Society
|June 14, 2021
Resumen
Las sulfoximinas quirales fueron sintetizadas utilizando un catalizador peptídico para la N-oxidación asimétrica. Este método proporciona una alta enantioselectividad y permite la fácil eliminación de grupos de dirección, dando valiosas sulfoximinas N-H.
Área de la Ciencia:
- Química orgánica
- Catálisis asimétrica
- Química medicinal
Sus antecedentes:
- Las sulfoximinas poseen propiedades químicas y biológicas únicas, lo que genera un interés significativo en la investigación.
- La síntesis asimétrica de sulfoximinas sigue siendo un desafío, con métodos catalíticos limitados disponibles.
- Las sulfoximinas quirales son bloques de construcción importantes en el descubrimiento de fármacos y la ciencia de los materiales.
Objetivo del estudio:
- Desarrollar un nuevo método catalítico asimétrico para la síntesis de sulfoximinas quirales.
- Investigar el uso de catalizadores peptídicos para la desimetrización de la N-oxidación de las piridil sulfoximinas.
- Explorar la influencia de la modificación del sustrato y la estructura del catalizador en la enantioselectividad.
Principales métodos:
- Desimetrización de la N-oxidación de las piridil sulfoximinas utilizando un catalizador de péptidos que contiene ácido aspártico.
- Empleando grupos de dirección en el sustrato para mejorar la enantioinducción.
- Utilizando péptidos con diferentes grupos protectores C-terminales (éster metílico frente a amida metílica) para controlar la formación de enantiómeros.
Principales resultados:
- Síntesis exitosa de óxidos quirales de sulfoximina con relaciones enantioméricas altas (hasta 99:1 er).
- Demostrar que los grupos de dirección mejoran significativamente la enantioinducción y pueden eliminarse fácilmente.
- Observación de la formación de enantiómeros opuestos basados en el grupo protector C-terminal del catalizador peptídico.
Conclusiones:
- Se ha establecido una nueva y eficiente síntesis asimétrica catalizada por péptidos de sulfoximinas quirales.
- El método desarrollado ofrece una vía versátil para obtener sulfoximinas N-H enriquecidas enantioméricamente.
- Un modelo de unión propuesto explica la enantioselectividad observada, destacando el papel del catalizador en el control de los resultados estereoquímicos.
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