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El ion tionio inició la formación de anillos de tamaño mediano: la síntesis total de asteriscunolida D
Barry M Trost1, Aaron C Burns, Mark J Bartlett
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|January 13, 2012
Resumen
Los investigadores lograron la primera síntesis de asteriscunolida D, un producto natural. Este proceso de nueve pasos creó eficientemente el macrociclo tensado, produciendo la forma más biológicamente activa.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de Productos Naturales.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
Sus antecedentes:
- Los productos naturales de humuleno exhiben una actividad biológica significativa.
- El Asteriscunolide D es una molécula compleja con una compleja estructura de anillo de 11 miembros.
- Las rutas sintéticas anteriores no han tenido acceso a la forma más biológicamente activa de asteriscunolida D.
Objetivo del estudio:
- Para lograr la primera síntesis total de asteriscunolida D.
- Desarrollar una estrategia sintética libre de grupos protectores.
- Para acceder al isómero más biológicamente activo de asteriscunolida D.
Principales métodos:
- El ion tionio diastereoselectivo inició la ciclización para formar el anillo de 11 miembros.
- Activación-eliminación del tioéter estereospecífico para la formación selectiva de E-olefinas.
- La adición enantioselectiva catalizada por Zn-ProPhenol y el acoplamiento alqueno-alquino catalizado por Ru para el control estereoquímico y la formación de butenolidos.
Principales resultados:
- Síntesis exitosa en nueve pasos de asteriscunolida D sin grupos protectores.
- Formación del macrociclo estirado de 11 miembros a través de una nueva estrategia de ciclización.
- Síntesis estereoselectiva que proporciona acceso al isómero más biológicamente activo de asteriscunolida D.
Conclusiones:
- La ruta sintética desarrollada es eficiente y evita proteger a los grupos.
- La síntesis proporciona un método confiable para acceder al asteriscunolida D. biológicamente activo.
- Este trabajo avanza en la síntesis de productos naturales complejos y facilita una mayor investigación biológica.
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