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Estructura y configuración absoluta de pigmentos espiroborados derivados de policetidos jurásicos obtenidos a partir

Klaus Wolkenstein¹, Han Sun², Heinz Falk³

¹Department of Geobiology, Geoscience Centre, University of Göttingen , Goldschmidtstraße 3, 37077 Göttingen, Germany.

Journal of the American Chemical Society

|October 8, 2015

Resumen

Los investigadores aclararon la estructura de los antiguos pigmentos que contienen boro, los borolitocromos, de las algas del Jurásico. Estos hallazgos vinculan las policetidas antiguas y modernas, revelando ideas evolutivas sobre la química de los productos naturales.

Área de la Ciencia:

Química de los productos naturales
Palacoquímica
Química orgánica

Sus antecedentes:

La aclaración estructural de los productos naturales, especialmente los metabolitos antiguos, es un desafío debido a la disponibilidad y la complejidad limitadas.
Los metabolitos secundarios antiguos ofrecen información sobre la historia evolutiva de los productos naturales.
Los productos naturales que contienen boro son raros y sus orígenes evolutivos son poco conocidos.

Objetivo del estudio:

Para determinar la estructura completa y la configuración absoluta de los borolitocromos, pigmentos enigmáticos de un organismo del Jurásico.
Investigar el origen y la importancia evolutiva de estos antiguos pigmentos que contienen boro.
Demostrar la utilidad de la RMN de la microcriosonda en el análisis de metabolitos antiguos.

Principales métodos:

Espectroscopia de RMN de la criosonda para la determinación estructural.
Espectroscopia de dicroísmo circular para la configuración absoluta.
Cálculos de la teoría funcional de la densidad para apoyar los hallazgos estructurales.

Principales resultados:

Se aclaró la estructura completa y la configuración absoluta de los borolitocromos, revelándolos como espiroboratos con ligandos pentacíclicos específicos.
La configuración del grupo sec-butilo se determinó como (S).
Se estableció un vínculo estructural entre los borolitocromos del Jurásico y la moderna poliquetida clostrubina, lo que sugiere un origen evolutivo común y una posible producción bacteriana.

Conclusiones:

Los borolitocromos representan los primeros policetidos aromáticos boronados descubiertos, fundamentalmente diferentes de los policetidos boronados conocidos.
Los hallazgos proporcionan evidencia de la preservación casi original de estos antiguos metabolitos secundarios.
El estudio pone de relieve la importancia evolutiva de los policetidos de tipo clostrubina y el potencial de la RMN de la microcriosonda para analizar biomoléculas antiguas.

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