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Una vía quimio-enzimática versátil para obtener ácidos alfa-aminoácidos ramificados beta-branqueados
Geoffrey J Roff1, Richard C Lloyd, Nicholas J Turner
1School of Chemistry, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JJ, U.K.
Journal of the American Chemical Society
|April 1, 2004
Resumen
Los investigadores sintetizaron análogos de beta-metil-beta-fenilalanina enantioméricamente puros mediante quimio y biocatálisis. Este nuevo enfoque proporciona acceso a los cuatro diastereoisómeros de estos valiosos compuestos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis por catálisis.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Los análogos de la beta-metil-beta-fenilalanina son bloques de construcción importantes en la química medicinal.
- El acceso a los diastereoisómeros enantioméricamente puros de estos compuestos puede ser un desafío.
- Los métodos sintéticos existentes pueden no proporcionar todos los estereoisómeros deseados de manera eficiente.
Objetivo del estudio:
- Desarrollar una estrategia sintética versátil para la preparación de análogos de beta-metil-beta-fenilalanina enantioméricamente puros.
- Para obtener los cuatro conjuntos posibles de diastereoisómeros para estos compuestos.
- Explorar el uso combinado de quimio y biocatálisis para la síntesis estereoselectiva.
Principales métodos:
- Síntesis de isómeros de ácidos didehidroamino (Z) beta, beta-disubstituidos a partir del éster metílico de la l-treonina.
- Hidrogenación asimétrica de los ácidos didehidroaminos mediante el uso de catalizadores quirales de rodio.
- Inversión enzimática estereoselectiva utilizando aminoácido oxidasa y un agente reductor.
Principales resultados:
- Se preparó con éxito una serie de análogos de beta-metil-beta-fenilalanina (1a-f) en forma enantioméricamente pura.
- Se obtuvieron dos conjuntos de diastereoisómeros a través de hidrogenación asimétrica e hidrólisis.
- Generó los dos conjuntos restantes de diastereoisómeros a través de la posterior estereoinversión.
Conclusiones:
- El enfoque combinado de quimioterapia y biocatálisis es efectivo para sintetizar diversos diastereoisómeros de análogos de beta-metil-beta-fenilalanina.
- Este método proporciona acceso a todas las formas estereoquímicamente distintas de estos valiosos compuestos.
- La estrategia ofrece una plataforma robusta para la generación de complejos derivados de aminoácidos.
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