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Síntesis de Bufospirostenin A y Ophiopogonol A por una ciclización de Prins transanular controlada por la

Peicheng Yang^1,2, Yan-Yu Li³, Hailong Tian²

¹Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China.

Journal of the American Chemical Society

|September 20, 2022

Resumen

Los investigadores lograron un control preciso sobre las conformaciones de anillo de tamaño medio utilizando condiciones no de Curtin-Hammett. Esto permitió la primera ciclización transanular cis-selectiva de Prins para una síntesis eficiente de esteroides.

Área de la Ciencia:

Química orgánica
Química sintética
Estereoquímica

Sus antecedentes:

El control de las conformaciones de anillo de tamaño medio es difícil debido a la flexibilidad y la deformación del anillo.
El desarrollo de métodos sintéticos selectivos para moléculas complejas sigue siendo un desafío clave.

Objetivo del estudio:

Desarrollar condiciones no-Curtin-Hammett para el control conformacional preciso de las ciclodecenonas.
Para lograr la primera ciclización transanular cis-selectiva de Prins.
Para permitir una síntesis concisa de esteroides complejos.

Principales métodos:

Se utilizaron condiciones no de Curtin-Hammett para el control conformacional de la ciclodecenona.
Se empleó una estrategia de ciclización de Prins transanular cis-selectiva.
Realizó estudios computacionales para dilucidar los mecanismos de reacción.

Principales resultados:

Se ha logrado un control preciso de la conformación de las ciclodecenonas.
Se informó de la primera ciclización transanular cis-selectiva de Prins.
Con éxito sintetizado bufospirostenin A y Ophiopogonol A en siete pasos.
Se ha identificado el control cinético y la dependencia de la vía (Prins frente al carbonilo) mediante el cálculo.

Conclusiones:

La isomerización conformacional influye críticamente en la estereoquímica del producto.
El método desarrollado ofrece una ruta concisa a los esteroides complejos.
Este trabajo proporciona una nueva estrategia para el control de las conformaciones de anillo de tamaño medio.

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