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Orquestación de ciclos de oxidación y reducción simultáneos para la estereoinversión y la desaracemización de los
Constance V Voss1, Christian C Gruber, Kurt Faber
1Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
Journal of the American Chemical Society
|September 30, 2008
Resumen
Este estudio demuestra la oxidación y reducción simultáneas en un solo recipiente, una tarea anteriormente imposible. Las enzimas permiten la desaracemización de los alcoholes en un solo recipiente utilizando el reciclaje simultáneo de cofactores oxidativos y reductivos.
Área de la Ciencia:
- La biocatálisis por biocatálisis.
- Química orgánica es la química orgánica.
- Química verde es la química verde.
Sus antecedentes:
- La oxidación y la reducción son procesos químicos opuestos.
- La oxidación y reducción simultáneas en un solo recipiente de reacción es un desafío.
- El reciclaje del cofactor es crucial para las transformaciones enzimáticas.
Objetivo del estudio:
- Para demostrar el reciclaje simultáneo del cofactor oxidativo y reductivo en un solo compartimento.
- Para lograr la desacimización de un solo bote de los alcoholes racémicos utilizando enzimas.
- Desarrollar una alternativa más ecológica a los métodos intensivos en químicos como la inversión Mitsunobu.
Principales métodos:
- Utilizando deshidrogenasas alcohólicas con preferencias estereofónicas y de cofactores opuestas.
- Implementando simultáneamente la oxidación enantioselectiva y la reducción asimétrica.
- Realización de reciclaje oxidativo de nicotinamida adenina dinucleótido fosfato (NADP +) y regeneración reductora de NADH simultáneamente.
Principales resultados:
- Se logró el reciclaje simultáneo del cofactor NADP+ y NADH sin interferencias significativas.
- Se realizó con éxito la desracemiación de un solo bote de los alcoholes secos racémicos a un solo enantiómero.
- Se ha demostrado la estereoinversión de los alcoholes, análoga a la reacción de Mitsunobu.
Conclusiones:
- El reciclaje enzimático simultáneo de cofactores es factible en un solo compartimento de reacción.
- Este enfoque ofrece un método "verde" y eficiente para las transformaciones de alcohol.
- La estrategia desarrollada proporciona un nuevo concepto para la síntesis asimétrica.
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