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Síntesis total de la (-) -calicifilina N
Artem Shvartsbart1, Amos B Smith
1Department of Chemistry, Laboratory for Research on the Structure of Matter, and Monell Chemical Senses Center, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|December 11, 2013
Resumen
La síntesis total del complejo alcaloide de Daphniphyllum (-) -calyciphylline N está ahora completa. Este logro utilizó estrategias sintéticas avanzadas, incluida una reacción intramolecular estereoselectiva Diels-Alder y una hidrogenación desafiante.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de Productos Naturales.
- Química Medicinal Química medicinal es el campo de la química medicinal.
Sus antecedentes:
- Los alcaloides de Daphniphyllum son una clase de productos naturales complejos con actividades biológicas potenciales.
- (-) -Calyciphylline N es un miembro estructuralmente intrincado de esta familia de alcaloides.
- El establecimiento de rutas sintéticas eficientes a tales moléculas complejas es crucial para futuras investigaciones.
Objetivo del estudio:
- Para lograr la primera síntesis total del complejo arquitectónico Daphniphyllum alcaloide (-) -calyciphylline N. para lograr la primera síntesis total del complejo arquitectónico Daphniphyllum.
- Desarrollar y mostrar nuevas metodologías sintéticas aplicables a la síntesis compleja de productos naturales.
Principales métodos:
- La síntesis empleó una reacción intramolecular Diels-Alder controlada por sustrato promovida por cloruro de dietilaluminio (Et2AlCl).
- Los pasos clave incluyeron una alquilación enolada transanular y una carbonilación Stille seguida de una ciclización de Nazarov.
- Una hidrogenación diastereoselectiva de un diene éster conjugado totalmente sustituido fue un paso crítico y de alto riesgo.
Principales resultados:
- Se logró con éxito la síntesis total de (-) -calicifilina N.
- La ruta sintética demostró una alta estereoselectividad en las transformaciones clave.
- El estudio pone de relieve la viabilidad de construir el complejo núcleo policíclico del alcaloide.
Conclusiones:
- La síntesis total de (-) -calyciphylline N proporciona una valiosa ruta hacia este complejo producto natural.
- Las estrategias sintéticas desarrolladas pueden aplicarse a la síntesis de otros alcaloides de Daphniphyllum.
- Este trabajo contribuye al campo de la síntesis orgánica y la química de productos naturales.
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