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Síntesis total de dapolhamina B y dapolhamina B lactona
Lian-Dong Guo1, Jieping Hou1, Wentong Tu1
1Department of Chemistry and Shenzhen Grubbs Institute , Southern University of Science and Technology , Shenzhen , China.
Journal of the American Chemical Society
|July 13, 2019
Resumen
Los investigadores lograron la primera síntesis total enantioselectiva del complejo alcaloide dapholdamina B de Daphniphyllum. Este avance proporciona una nueva vía sintética para los productos naturales de aza-adamantano.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- Los alcaloides de Daphniphyllum son conocidos por su complejidad estructural y bioactividades significativas.
- El núcleo único de aza-adamantano y los múltiples estereocentros de la dapoldamina B presentan desafíos sintéticos considerables.
Objetivo del estudio:
- Informar sobre la primera síntesis total enantioselectiva del producto natural dapoldamina B.
- Desarrollar una estrategia sintética concisa y eficaz para los productos naturales de aza-adamantano.
Principales métodos:
- Utilizó una reacción de Mannich viníloga como un paso clave.
- Se empleó una síntesis optimizada de cetonas α-bromo-α,β-insaturadas.
- Adición de aza-Michael intramolecular dependiente del sustrato incorporado y activación de amida para la anulación.
Principales resultados:
- Se ha sintetizado con éxito dapoldamina B y su derivado lactona enantioselectivamente.
- Se estableció una ruta sintética concisa con ocho estereocentros contiguos, incluidos tres completamente sustituidos.
- Se han demostrado transformaciones clave, incluida la lactonización de tipo SN2' y la olefinación de Horner-Wadsworth-Emmons.
Conclusiones:
- El enfoque sintético desarrollado representa la primera síntesis total de un producto natural de aza-adamantano.
- Este trabajo proporciona una valiosa metodología para acceder a estructuras complejas de alcaloides.
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