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Síntesis total de los triterpenoides isomalabaricanos
Yaroslav D Boyko1, Christopher J Huck1, David Sarlah1
1Roger Adams Laboratory, Department of Chemistry , University of Illinois , Urbana , Illinois 61801 , United States.
Journal of the American Chemical Society
|August 27, 2019
Resumen
Los investigadores lograron las primeras síntesis totales de triterpenoides isomalabaricanos citotóxicos, ácido rabdastrélico A y esteletina E. Este avance proporciona una estrategia general para acceder a estos productos naturales marinos desafiantes.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- Los triterpenoides isomalabaricanos son una clase de productos naturales marinos conocidos por su alta citotoxicidad.
- El núcleo trans-syn-trans-perhidrobenz[e]indeno complejo y forzado presenta un desafío sintético significativo.
- Las síntesis anteriores de estos compuestos han sido limitadas o no han tenido éxito.
Objetivo del estudio:
- Para lograr la primera síntesis total de ácido (±) rhabdastrélico A y (±) esteletina E.
- Desarrollar una estrategia general y eficiente para la síntesis de triterpenoides isomalabaricanos.
- Explorar nuevas metodologías sintéticas para la construcción de estructuras policíclicas complejas.
Principales métodos:
- Una síntesis lineal de 14 pasos de la geranilacetona comercial.
- Utilizó una ciclización de polieno radical reductor para formar la estructura del núcleo.
- Se empleó una cicloisomerización oxidativa de Rautenstrauch sin precedentes.
- Incorporación de una α-sustitución de un p-toluenesulfonilhidrazona con transposición reductora in situ.
- Se aplicó un acoplamiento cruzado de última etapa para la construcción de cadenas laterales.
Principales resultados:
- Se ha sintetizado con éxito ácido (±) rhabdastrélico A y (±) esteletina E.
- Eficientemente construido el núcleo de trans-sin-trans-perhidrobenz[e]indeno característico.
- Demostró un enfoque modular para sintetizar diversas cadenas laterales poliinsaturadas.
- Se estableció una estrategia general aplicable a otros miembros de la familia de los isomalabaricanos.
Conclusiones:
- La ruta sintética desarrollada es eficiente y general para acceder a triterpenoides marinos difíciles.
- Las nuevas metodologías emplearon nuevas vías abiertas para la síntesis de moléculas complejas.
- Este trabajo hace que los productos naturales marinos citotóxicos anteriormente inaccesibles estén disponibles para futuras investigaciones biológicas.
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