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Síntesis total de (-) -Psatirina A habilitada por la ciclización radical
Weizhao Zhao1, Reem Al-Ahmad1, Mingji Dai1,2
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Journal of the American Chemical Society
|August 25, 2025
Resumen
Este estudio presenta la primera síntesis total enantioselectiva del diterpeno (-) -psatirina A antibacteriano. La síntesis de 19 pasos presenta nuevos métodos para construir su complejo marco tetraciclico y tres centros cuaternarios contiguos de carbono.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- La (-) -psatirina A es un diterpeno antibacteriano producto natural.
- Posee un complejo esqueleto de carbono tetraciclico 6/4/5 con siete estereocentros contiguos.
- Tres de estos estereocentros son centros cuaternarios adyacentes de carbono, lo que plantea un desafío sintético significativo.
Objetivo del estudio:
- Para lograr la primera síntesis total enantioselectiva de (-) -psatirina A.
- Desarrollar y aplicar nuevas metodologías sintéticas para la construcción de productos naturales complejos.
- Establecer rutas eficientes para acceder a moléculas con características estereocímicas difíciles.
Principales métodos:
- Adición de cobre enantioselectivo y conjugado catalizado por NHC.
- Reacción de coniaeno catalizada por oro para la construcción de anillos cíclicos.
- Acoplamiento de olefinas reductoras de Baran (ciclización de radicales olefinas-enonas iniciada por MHAT) para la formación de anillos de cuatro miembros y tercera instalación de centro cuaternario de carbono.
Principales resultados:
- Construcción exitosa del esqueleto de carbono tetraciclico único de la (-) -psatirina A.
- Establecimiento de siete estereocentros contiguos, incluidos tres centros cuaternarios de carbono adyacentes.
- Finalización de la síntesis total en 19 pasos, demostrando la eficacia de la estrategia desarrollada.
Conclusiones:
- Se logró la primera síntesis total enantioselectiva de (-) -psatirina A.
- La ruta sintética muestra el poder de los métodos catalíticos modernos, incluidos el cobre, el oro y las ciclizaciones radicales.
- Este trabajo proporciona una vía viable para la síntesis de (-) -psatirina A y diterpenoides complejos relacionados.
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