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Dominación de aldehídos altamente enolizables mediante catálisis enzimática para la construcción

Huangong Li¹, Zheng Zhu¹, Dongqi Wu¹

¹State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.

Journal of the American Chemical Society

|January 17, 2025

Resumen

Este estudio introduce un nuevo método enzimático para el acoplamiento catalítico asimétrico C-C de aldehídos de 2-fosfonato desafiantes. El proceso produce selectivamente β-hidroxifosfonatos biológicamente activos con alta eficiencia y enantioselectividad.

Área de la Ciencia:

Química orgánica
Biocatálisis
Ingeniería de enzimas

Sus antecedentes:

El acoplamiento catalítico asimétrico C-C de aldehídos altamente enolizables es difícil.
Los métodos existentes a menudo producen mezclas complejas, lo que limita su utilidad.

Objetivo del estudio:

Desarrollar un método enzimático selectivo para el acoplamiento C-C de aldehídos de 2-fosfonato.
Para sintetizar β-hidroxifosfonatos biológicamente activos con alto rendimiento y enantioselectividad.

Principales métodos:

Utilizó enzimas dependientes del difosfato de tiamina (ThDP) (PfBAL y PaBAL) para el acoplamiento C-C.
Se emplean nucleófilos dinámicamente reversibles generados in situ (aniones acilo).
Se han investigado las direcciones de entrada del sitio activo de la enzima a través de estudios mecanicistas.

Principales resultados:

Se obtiene una producción selectiva de β-hidroxifosfonatos con rendimientos de hasta el 95% y enantioselectividades de hasta el 99% ee.
Capacidad demostrada de síntesis a escala de gramos.
Pares de enzimas enantiocomplementarias identificadas (PfBAL y PaBAL) para acceder a las dos configuraciones del producto.

Conclusiones:

El acoplamiento enzimático C-C ofrece una alternativa superior a las reacciones mediadas por NHC para los aldehídos de 2-fosfonato.
El método desarrollado proporciona acceso a diversas moléculas biológicamente activas.
Las distintas geometrías del sitio activo de la enzima dictan el resultado estereoquímico de la reacción.

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