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El uso de fragmentos no convencionales permite una síntesis total concisa de (-) -Callyspongiolide
Francesco Manoni1, Corentin Rumo1, Liubo Li1
1Department of Chemistry and Biochemistry, University of California-Los Angeles , 607 Charles E. Young Drive East, Los Angeles, California 90095-1569, United States.
Journal of the American Chemical Society
|January 16, 2018
Resumen
Este estudio detalla una nueva síntesis asimétrica de (-) -callyspongiolide, construyendo el núcleo de macrolide de un disacárido y monoterpene. El enfoque innovador utiliza la catálisis de iridio quiral para el acoplamiento de fragmentos y una estrategia de fragmentación única para la macrolactonización.
Área de la Ciencia:
- Química orgánica
- Química sintética
- Síntesis de productos naturales
Sus antecedentes:
- (-) -Callyspongiolide es un producto natural marino complejo con actividades biológicas potenciales.
- Las rutas sintéticas anteriores para los macrólidos a menudo implican productos intermedios de secoácidos difíciles.
Objetivo del estudio:
- Desarrollar una nueva y eficiente síntesis asimétrica de (-) -callyspongiolide.
- Explorar una estrategia atípica para la construcción de núcleos de macrólidos, evitando los intermediarios de secoácidos.
Principales métodos:
- Síntesis asimétrica que utiliza la catálisis de iridio quiral para el acoplamiento de fragmentos.
- Construcción estereoselectiva y regioselectiva de productos intermedios clave mediante fragmentación perhemiketal.
- La macrolactonización carbonilativa para la formación de macrociclos.
Principales resultados:
- Se logró una síntesis directa y flexible de (-) -calispongiolida.
- El dominio macrolido fue construido atípicamente a partir de un disacárido y un monoterpeno.
- El control estereoquímico y regioquímico se mantuvo durante toda la síntesis.
Conclusiones:
- La ruta sintética descrita ofrece un nuevo paradigma para la síntesis de macrólidos.
- Este método proporciona un acceso flexible y eficiente al (-) -calispongiolido y, potencialmente, a otros macrolidos complejos.
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