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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Síntesis concisa de los iminociclitoles a través de la aminociclación de tipo Petasis
Zhangyong Hong1, Lei Liu, Masakazu Sugiyama
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|June 18, 2009
Resumen
Un nuevo método de síntesis en dos pasos produce eficientemente iminociclitoles biológicamente importantes a partir de derivados de azúcares utilizando la condensación tipo Petasis. Este enfoque general y simple produce valiosos compuestos de iminociclitol con inesperadas diastereoselectividades.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Química de los carbohidratos Química de los carbohidratos
Sus antecedentes:
- Los iminociclitoles son imitaciones cruciales de carbohidratos con diversas actividades biológicas.
- Las rutas sintéticas existentes pueden ser complejas y de alcance limitado.
Objetivo del estudio:
- Desarrollar un método general y operacionalmente simple para la síntesis de iminociclitoles biológicamente importantes.
- Explorar el alcance y la diastereoselectividad de la estrategia sintética desarrollada.
Principales métodos:
- Una síntesis en dos pasos que emplea la condensación de tipo Petasis.
- Utilizando derivados de azúcar fácilmente accesibles como materiales de partida.
- Caracterización de los productos de iminociclitol sintetizados.
Principales resultados:
- Síntesis exitosa de varios iminociclitoles en rendimientos moderados a buenos (44-60%).
- Demostración de la generalidad del método y la simplicidad operativa.
- Observación de diastereoselectividades inesperadas, que insinúan intermediarios de reacción específicos.
Conclusiones:
- El método de dos pasos desarrollado proporciona una ruta eficiente y versátil a los iminociclitoles biológicamente significativos.
- Las diastereoselectividades observadas ofrecen información sobre el mecanismo de reacción, que potencialmente involucra intermediarios cíclicos de iones de iminio.
- Este enfoque facilita el acceso a diversas estructuras de iminociclitol a partir de precursores fácilmente disponibles.
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