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Síntesis total enantioselectiva de (+) y (-) -nigellamina A2

Jianwei Bian¹, Matthew Van Wingerden, Joseph M Ready

¹Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, Texas 75390-9038, USA.

Journal of the American Chemical Society

|June 8, 2006

Resumen

Los investigadores lograron la síntesis total de nigellamina A2, dolabellano, diterpenos conocidos por promover el metabolismo de los lípidos. Este avance confirma la estereoquímica absoluta y abre caminos a los alcaloides relacionados.

Área de la Ciencia:

Química orgánica es la química orgánica.
Síntesis de Productos Naturales.
Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.

Sus antecedentes:

Los alcaloides de la nigelamina son los diterpenos de la dolabellana.
Estos compuestos exhiben una potente actividad promotora del metabolismo lipídico.

Objetivo del estudio:

Para lograr la síntesis total de (+) y (-) -nigellamina A2.
Para establecer la estereoquímica absoluta de la nigellamina sintética A2.
Para explorar rutas sintéticas para otros alcaloides de nigellamina.

Principales métodos:

La alquilación alílica asimétrica intramolecular mediante el uso de un catalizador Pd ((fosfinoxazolina).
La alquinilación radical.
Ciclificación Nozaki-Hiyama-Kishi diastereoselectiva por catástrofe. ciclificación Nozaki-Hiyama-Kishi. también conocida como ciclificación Nozaki-Hiyama.
Epoxidación catalítica regionalizada y estereoselectiva.
Análisis cristalográfico de rayos X de un intermediario ópticamente activo.

Principales resultados:

Síntesis total exitosa de (+) y (-) -nigellamina A2.
Confirmación de la estereoquímica absoluta de la nigellamina A2.
Demostración de las transformaciones sintéticas clave que permiten el acceso a compuestos relacionados.

Conclusiones:

Se ha logrado la síntesis total de nigelamina A2.
La estereoquímica absoluta fue confirmada a través de la síntesis y la cristalografía de rayos X.
La estrategia sintética desarrollada puede ser adaptada para otros alcaloides de nigellamina.

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