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A Strategy for Sensitive, Large Scale Quantitative Metabolomics
Published on: May 27, 2014
Síntesis total enantioselectiva del semperósido a
Paolo Piccinini1, Giovanni Vidari, Giuseppe Zanoni
1Dipartimento di Chimica Organica, Università di Pavia, Italy.
Journal of the American Chemical Society
|April 22, 2004
Resumen
Una nueva síntesis de 10 pasos de semperoside A proporciona la primera síntesis total de este glucósido iridoide. Este método crea eficientemente la estructura compleja y confirma su estereoquímica.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Síntesis de Productos Naturales.
Sus antecedentes:
- El semperósido A posee una estructura única de iridano glucosilado.
- Los glucósidos iridoides son una clase significativa de productos naturales con diversas actividades biológicas.
- La síntesis de complejos glucósidos iridoides presenta desafíos, particularmente en el control de la estereoquímica y la glucosidación.
Objetivo del estudio:
- Desarrollar una estrategia sintética concisa y enantioselectiva para el semperoside A.
- Para establecer la primera síntesis total de semperósido A.
- Para probar inequívocamente la estereocímica absoluta del semperósido A.
Principales métodos:
- Desarrollo de una nueva ruta sintética que emplee una ciclización de heteroatomos electrófilos mediada por Hg (II).
- Instalación estereoselectiva de estereocentros C-2 y C-3.
- Utilizando una lactona enantioméricamente pura como material de partida.
Principales resultados:
- Logró la primera síntesis total de semperoside A en 10 pasos.
- Obtuvo un rendimiento general del 17%.
- Controlaron con éxito la estereoquímica durante la formación del esqueleto iridano.
Conclusiones:
- La estrategia desarrollada es versátil y eficiente para sintetizar semperoside A.
- La síntesis supera los desafíos asociados con la glucosidación hemiacetal en la síntesis de glucósidos iridoides.
- La estereoquímica absoluta del semperosídeo A ha sido inequívocamente confirmada.
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