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Síntesis total enantioselectiva concisa de la (+) - punctaporonina U

Paul Gri¹, Qian Wang¹, Jieping Zhu¹

¹Laboratory of Synthesis and Natural Products (LSPN), Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH5304, CH-1015 Lausanne, Switzerland.

Journal of the American Chemical Society

|October 22, 2025

Resumen

Este estudio detalla la primera síntesis total enantioselectiva de (+) -punctaporonina U, un sesquiterpeno complejo. La síntesis eficiente de seis pasos establece ocho estereocentros contiguos utilizando nuevas transformaciones químicas.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Síntesis estereoselectiva

Sus antecedentes:

La punctaporonina U es un sesquiterpeno pentacíclico complejo parecido a una jaula.
Su intrincada estructura presenta ocho estereocentros contiguos, lo que plantea un desafío sintético significativo.

Objetivo del estudio:

Para lograr la primera síntesis total enantioselectiva de (+) -punctaporonina U.
Desarrollar una vía sintética eficiente para este complejo producto natural.

Principales métodos:

Se empleó una adición Mukaiyama-Michael cis selectiva.
Una secuencia de adición oxa-Michael / reacción de aldol / brominación construyó sistemas de anillo de llave.
Un desplazamiento intramolecular de S_N2 formó el anillo tetrahidrofurano.

Principales resultados:

Se logró con éxito la síntesis total de (+) - punctaporonina U.
La síntesis se completó en seis pasos a partir de un derivado de ciclopentenona fácilmente disponible.
Se establecieron ocho estereocentros contiguos con alta enantioselectividad.

Conclusiones:

Este trabajo proporciona una ruta eficiente y enantioselectiva a la (+) -punctaporonina U.
La estrategia sintética destaca la utilidad de las transformaciones clave para la construcción de moléculas policíclicas complejas.
Esta síntesis abre caminos para una mayor exploración de la química de los sesquiterpenos.

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