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La síntesis total de la calcitrina
Ming Yang1, Fangjie Yin1, Haruka Fujino1
1Department of Chemistry , University of Chicago , 5735 South Ellis Avenue , Chicago , Illinois 60637 , United States.
Journal of the American Chemical Society
|March 1, 2019
Resumen
Los investigadores lograron la primera síntesis total del pigmento amarillo calcitrina, un dímero de ácido pulvino. Esto implicó nuevas estrategias sintéticas y aclaró su forma natural, avanzando en la química de productos naturales.
Área de la Ciencia:
- Química orgánica
- Síntesis de productos naturales
- Química medicinal
Sus antecedentes:
- La calcitrina es un pigmento amarillo que se encuentra en el hongo Chalciporous piperatus.
- Su estructura única de dímeros de ácido pulvino presenta un desafío sintético.
- La caracterización anterior lo identificó como un ácido libre, pero este estudio sugiere lo contrario.
Objetivo del estudio:
- Para lograr la primera síntesis total de la calcitrina.
- Para explorar rutas sintéticas eficientes para su complejo núcleo policíclico.
- Para aclarar la forma natural exacta de la calcitrina.
Principales métodos:
- Una síntesis lineal de 17 pasos a partir de materiales de partida disponibles en el mercado.
- Se utilizó la reacción de Coniano catalizada por oro para la construcción del núcleo.
- Adición de acilona mediada por carbenos N-heterocíclicos empleados para la formación de núcleos policíclicos.
- Se introdujeron cadenas laterales a través de un acoplamiento doble Stille de última etapa.
Principales resultados:
- El éxito de la síntesis total de la calcitrina.
- Demostró la eficacia de la catálisis de oro (I) y de carbenos heterocíclicos en la construcción del núcleo.
- Desafíos identificados con diseños sintéticos alternativos debido al obstáculo estérico.
- Reveló que el material caracterizado originalmente era la sal carboxilada, no el ácido libre.
Conclusiones:
- Se logró la primera síntesis total de calcitrina.
- El estudio destaca la utilidad de las reacciones catalíticas específicas para la síntesis de moléculas complejas.
- Corregido el entendimiento de la forma natural de la calcitrina, impactando en la investigación y caracterización futuras.
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