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Glicosilación catalítica para donantes y aceptores con una protección mínima

Qiu-Di Dang¹, Yi-Hui Deng^2,3, Tian-Yu Sun^2,3

¹State Key Laboratory of Biotherapy and Cancer Center, West China Hospital and School of Chemical Engineering, Sichuan University, Chengdu, China.

|June 17, 2024

Resumen

Los químicos desarrollaron una nueva plataforma catalítica para sintetizar oligosacáridos complejos. Este método permite la glicosilación selectiva de azúcares no protegidos, simplificando el proceso y permitiendo la creación de intrincadas cadenas de azúcares.

Área de la Ciencia:

Química de los carbohidratos
Síntesis orgánica
Glicobiología

Sus antecedentes:

Los oligosacáridos juegan un papel crucial en los procesos biológicos, lo que hace necesaria su síntesis para estudios funcionales.
La síntesis tradicional de oligosacáridos depende en gran medida de las estrategias de protección del grupo, que son laboriosas y requieren mucho tiempo.
El logro de la selectividad de sitio, estereo y quimica en la O-glucosilación de azúcares estructuralmente complejos sigue siendo un desafío significativo.

Objetivo del estudio:

Desarrollar un método eficiente y selectivo para la síntesis de oligosacáridos.
Para permitir el acoplamiento de azúcares no protegidos o mínimamente protegidos.
Para lograr la formación de 1,2-cis-O-glucósidos controlada por el catalizador.

Principales métodos:

Activación a base de radicales de las glicosil sulfonas de alilo para generar bromuros de glicosilo reactivos.
Utilizando un catalizador de ácido aminoborónico diseñado para mediar la transferencia de glucosilo a través de interacciones covalentes no covalentes y reversibles.
El uso de diferentes catalizadores de ácido aminoborónico para controlar la selectividad del sitio de la glicosilación.

Principales resultados:

Se estableció una nueva plataforma de glicosilación que permite el acoplamiento selectivo de azúcares no protegidos.
El método produjo con éxito 1,2-cis-O-glucósidos de una manera controlada por el catalizador y selectiva del sitio.
La plataforma demostró un amplio alcance de sustrato, permitiendo la síntesis de oligosacáridos complejos, incluidos los pentasacáridos con múltiples hidroxilos libres.

Conclusiones:

La plataforma catalítica desarrollada simplifica significativamente la síntesis de oligosacáridos al minimizar la necesidad de proteger grupos.
La selectividad del sitio controlada por catalizador ofrece un control sin precedentes sobre el ensamblaje de oligosacáridos.
Este enfoque proporciona una herramienta poderosa para acceder a los carbohidratos complejos e investigar sus funciones biológicas.

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