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La sinergia de síntesis, cálculo y RMN revela estructuras correctas de baulamicina

Jingjing Wu¹, Paula Lorenzo¹, Siying Zhong¹

¹School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.

|July 28, 2017

Resumen

Los investigadores desarrollaron un nuevo método para determinar las estructuras de productos naturales complejos, como las baulamicinas, utilizando resonancia magnética nuclear (RMN) y teoría funcional de la densidad. Este enfoque aclara rápidamente las estructuras moleculares, ayudando al descubrimiento de fármacos.

Área de la Ciencia:

Química de los productos naturales
Química medicinal
Síntesis orgánica

Sus antecedentes:

Los productos naturales biológicamente activos son fuentes cruciales de nuevos medicamentos.
Determinar la estructura de moléculas complejas, especialmente aquellas con cadenas flexibles, es un desafío.
Se encontró que las asignaciones estructurales anteriores para las baulamicinas eran incorrectas.

Objetivo del estudio:

Desarrollar un método potente para el esclarecimiento estructural rápido de productos naturales conformacionalmente flexibles.
Para determinar las estructuras correctas de las baulamicinas (A y B).

Principales métodos:

Predicción de los parámetros de la resonancia magnética nuclear (RMN) utilizando la teoría funcional de la densidad (TFD).
Secuencia eficiente de transformaciones sintéticas basadas en el boro.
Preparación de una mezcla codificada (etiquetada) de diastereómeros de productos naturales.

Principales resultados:

Se estableció un método novedoso y poderoso para la aclaración estructural rápida.
Se identificaron y sintetizaron las estructuras correctas de las baulamicinas.
El estudio destaca la utilidad de los parámetros de RMN predichos por DFT en la determinación de la estructura de moléculas complejas.

Conclusiones:

El método desarrollado permite una determinación estructural rápida y precisa de productos naturales difíciles.
Este enfoque acelera el proceso de identificación y síntesis de posibles nuevos fármacos candidatos.
La asignación estructural precisa es fundamental para comprender y utilizar la actividad biológica de los productos naturales.

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