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Updated: Jul 15, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

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Síntesis totales enantioselectivas de (-) - caulamidina D y (-) - isocaulamidina D y su reasignación de la

Haiyong Yu¹, Junhao Zhang¹, Dongxu Ma¹

¹Molecular Synthesis Center and Key Laboratory of Marine Drugs, MOE, and School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.

Journal of the American Chemical Society

|October 4, 2023

Resumen

Las primeras síntesis totales enantioselectivas de (-) -caulamidina D y (-) -isocaulamidina D se lograron utilizando una estrategia unificada de 16 pasos. Las reacciones clave incluyeron reorganización asimétrica y ciclización en cascada, confirmando sus formas de sales de TFA.

Área de la Ciencia:

Química orgánica
Síntesis total
Química de los productos naturales

Sus antecedentes:

La (-) caulamidina D y la (-) isocaulamidina D son productos naturales complejos.
Su estereoquímica y forma natural (sales de TFA) no estaban claras anteriormente.

Objetivo del estudio:

Lograr las primeras síntesis totales enantioselectivas de (-) -caulamidina D y (-) -isocaulamidina D.
Para determinar sin ambigüedades sus configuraciones absolutas y formas naturales.

Principales métodos:

Se empleó una estrategia sintética unificada de 16 pasos.
Las etapas clave incluyeron un reordenamiento asimétrico Meerwein-Eschenmoser-Claisen para la construcción del estereocentro.
Se utilizó una ciclización en cascada de 6-exo-dig/6-exo-tetamina/nitrilo.

Principales resultados:

Se lograron síntesis totales enantioselectivas exitosas de (-) -caulamidina D (5) y (-) -isocaulamidina D (6).
La cristalografía de rayos X confirmó las configuraciones absolutas de ambos compuestos.
Las muestras naturales aisladas se identificaron como sales de trifluoroacetato (TFA), no como formas neutras.

Conclusiones:

El estudio proporciona las primeras síntesis totales de estos productos naturales desafiantes.
La ruta sintética destaca metodologías novedosas para la construcción y la ciclización de estereocentros.
La caracterización definitiva de las formas naturales como sales de TFA aclara su identidad química.

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