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La ciclopropanación de olefinas a través de la transferencia de carbenos catalizada por enzimas modificadas del
Pedro S Coelho1, Eric M Brustad, Arvind Kannan
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|December 22, 2012
Resumen
Los investigadores diseñaron enzimas del citocromo P450 para realizar reacciones de transferencia de carbenos, lo que permite la síntesis de estirenos ciclopropanados. Este avance crea un método biológico para una reacción clave de síntesis orgánica previamente desconocida en la naturaleza.
Área de la Ciencia:
- La biocatálisis por biocatálisis.
- Síntesis orgánica La síntesis orgánica.
- Ingeniería de enzimas Ingeniería de enzimas Ingeniería de enzimas
Sus antecedentes:
- Los catalizadores de metales de transición son vitales para la funcionalización de los enlaces C=C y C-H a través de las transferencias de carbenos, nitreno y oxeno.
- Las enzimas del citocromo P450 son los catalizadores de la naturaleza para las transferencias de oxenos, pero no se observa la transferencia biológica de carbenos a las olefinas.
- La transferencia de carbenos a olefinas es una reacción crucial para la formación de enlaces C-C en la química orgánica sintética.
Objetivo del estudio:
- Para diseñar variantes del citocromo P450 (((BM3) capaces de catalizar las reacciones de transferencia de carbenos.
- Para lograr una ciclopropanación altamente diastereoselectiva y enantioselectiva de estirenos utilizando enzimas de ingeniería.
- Demostrar la adaptación de las enzimas naturales para reacciones sintéticamente relevantes que no existen en la naturaleza.
Principales métodos:
- Ingeniería de proteínas de las variantes del citocromo P450 (((BM3).
- Catálisis de las reacciones de ciclopropanación utilizando reactivos diazoéstricos.
- Análisis estereoquímico de los productos de ciclopropanación.
Principales resultados:
- Las variantes del citocromo P450 (((BM3) modificadas por ingeniería catalizaron con éxito la transferencia de carbenos a estirenos.
- La ciclopropanación enzimática procedió con una alta diastereoselectividad y enantioselectividad.
- Se propuso un mecanismo de transferencia de carbenos putativo para la enzima diseñada.
Conclusiones:
- La ingeniería enzimática puede adaptar enzimas naturales como las P450 para nuevas transformaciones sintéticas.
- Este trabajo establece una ruta biocatalítica para la ciclopropanación enantioselectiva, una reacción clave en la síntesis orgánica.
- Los P450 diseñados ofrecen una alternativa sostenible y selectiva a los catalizadores metálicos tradicionales para la transferencia de carbenos.
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