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Síntesis totales de las tetrapetalonas A y C (+) y (-)

Heemal H Dhanjee¹, Yutaka Kobayashi¹, Jonas F Buergler¹

¹Department of Chemistry and Biochemistry, Baylor University , One Bear Place 97348, Waco, Texas 76798, United States.

Journal of the American Chemical Society

|October 10, 2017

Resumen

Las síntesis de tetrapetalonas A y C se lograron utilizando una nueva estrategia de 12 pasos. Este método permite la creación de productos naturales y sus enantiómeros, ampliando el alcance de la síntesis de poliqueturo.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química medicinal

Sus antecedentes:

Las policetidas son una clase diversa de productos naturales con actividades biológicas significativas.
Las tetrapetalonas A y C son policetidas de origen natural con potenciales aplicaciones terapéuticas.
Las rutas sintéticas eficientes para estos compuestos son cruciales para una mayor investigación biológica y el desarrollo de fármacos.

Objetivo del estudio:

Desarrollar una síntesis concisa y eficiente de las (-) -tetrapetalonas A y C y sus enantiómeros.
Explorar la utilidad de la activación de C-H y la ciclización de Heck en la construcción del marco aglicónico central.
Establecer un método para resolver la aglicona y acceder a ambas series enantioméricas.

Principales métodos:

Se sintetizó un ácido tetrámico N-arilo enmascarado como material de partida clave.
Se empleó una secuencia de adición conjugada/acilación intramolecular de Friedel-Crafts para formar un intermediario de azepina.
Se utilizó la química de activación de C-H seguida de la ciclización de Heck para ensamblar el marco de agliconas.
Se utilizó la glucosilación estereospecífica y la separación diastereomérica para la resolución enantiomérica.

Principales resultados:

Se logró una síntesis total de (-) -tetrapetalonas A y C y sus enantiómeros en 12 pasos.
La estrategia sintética incorporó con éxito la activación de C-H y la ciclización de Heck.
La resolución enantiomérica se realizó de manera eficiente a través de la separación diastereomérica después de la glucosilación.

Conclusiones:

La vía sintética desarrollada en 12 pasos proporciona acceso a las tetrapetalonas A y C y sus enantiómeros.
El estudio destaca el poder de las metodologías sintéticas modernas, incluida la activación de C-H, para la síntesis de productos naturales.
Este trabajo facilita una mayor exploración de las actividades biológicas y las aplicaciones potenciales de las tetrapetalonas.

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