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Síntesis total asimétrica de las bufogarrizinas gemelas A y B

Li-Ping Zhong¹, Rui Feng¹, Jing-Jing Wang¹

¹Shenzhen Grubbs Institute, Department of Chemistry, Guangdong Provincial Key Laboratory of Catalytic Chemistry, Southern University of Science and Technology, Shenzhen 518055, China.

Journal of the American Chemical Society

|January 19, 2023

Resumen

Los investigadores lograron la primera síntesis total asimétrica de las bufogarrizinas A y B, esteroides gemelos complejos. Se emplearon nuevas estrategias sintéticas, incluida una cicloadición catalizada por Ru [5 + 2], para construir sus marcos tetraciclicos únicos.

Área de la Ciencia:

Química orgánica
Síntesis de productos naturales
Química medicinal

Sus antecedentes:

Las bufogarrizinas A y B son esteroides gemelos inusuales y altamente oxigenados.
Estos esteroides poseen sistemas de anillos tetraciclicos complejos y reordenados ([7-5-6-5] y [5-7-6-5]).
Sus intrincadas estructuras presentan importantes desafíos sintéticos.

Objetivo del estudio:

Para lograr la primera síntesis total asimétrica de las bufogarrizinas A y B.
Desarrollar nuevas metodologías sintéticas para la construcción de productos naturales policíclicos complejos.
Para explorar el espacio químico alrededor de estas estructuras esteroides únicas.

Principales métodos:

Reacción de cicloadición catalisada por rutenio [5+2] intramolecular.
El éter vinílico ciclopropano-iño como sustrato clave.
Las reacciones de cascada de aldol retro-aldol/transanular.
Estrategias de síntesis asimétricas.

Principales resultados:

Construcción eficiente del núcleo tetraciclico [7-5-6-5] de la bufogargarizina A.
Construcción diastereoselectiva del esqueleto tetraciclico [5-7-6-5] de la bufogarrizina B.
Demostración de nuevas vías sintéticas para la síntesis de esteroides complejos.

Conclusiones:

Se ha logrado con éxito la primera síntesis total asimétrica de bufogarrizinas A y B.
Las nuevas estrategias sintéticas, incluida la cicloadición catalizada por Ru y las cascadas de aldol, permiten el acceso a arquitecturas esteroideas complejas.
Este trabajo proporciona una base para investigaciones adicionales sobre las actividades biológicas y los análogos estructurales de estos productos naturales.

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