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Síntesis estereoselectiva de ácidos oligo-alfa-(2,8)-siálico y sus derivados
Hiroshi Tanaka1, Yuji Nishiura, Takashi Takahashi
1Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology 2-12-1-S1-35, Oookayama, Meguro, Tokyo 152-8552, Japan. thiroshi@apc.titech.ac.jp
Journal of the American Chemical Society
|June 1, 2006
Resumen
Este estudio presenta una síntesis eficiente de alfa2,8-oligosialosídeos. Un nuevo donante de sialilo protegido permite la producción de alto rendimiento de oligosialosidos complejos, incluido el ácido tetra-alfa-2,8-sialico.
Área de la Ciencia:
- Química de los carbohidratos Química de los carbohidratos
- Síntesis orgánica La síntesis orgánica.
- Glucobiología Glucobiología.
Sus antecedentes:
- Los oligosialosídeos juegan un papel crucial en los procesos biológicos.
- La síntesis eficiente de las estructuras de ácido siálico ligadas a alfa-2,8 es un desafío.
- La comprensión de estas estructuras requiere métodos sintéticos fiables.
Objetivo del estudio:
- Desarrollar una síntesis eficiente y elegante de alfa-2,8-oligosialosídeos.
- Para investigar la utilidad de un nuevo donante de sialilo protegido.
- Para sintetizar el ácido tetra-alfa (2,8) -sialico.
Principales métodos:
- Síntesis utilizando un donante de sialilo protegido con 5-N,4-O-carbonilo.
- Reacciones de alfa-sialización en el diclorometano (CH2Cl2).
- Glicosidación y protocolos de desprotección.
Principales resultados:
- Se obtuvieron excelentes rendimientos de alfa-2,8- y alfa-2,9-disialosidos.
- El grupo protector 5-N,4-O-carbonilo aumentó la reactividad de los grupos hidroxilo C8.
- Se logró una síntesis exitosa de ácido tetra-alfa ((2,8) -sialico.
Conclusiones:
- El método desarrollado proporciona una ruta eficiente a las alfa-2,8-oligosialosídeos.
- El donante de sialilo protegido es eficaz para la alfa-sialización.
- Esta síntesis facilita más estudios sobre las funciones biológicas de los oligosialosidos.
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