Video Experimental Relacionado

Updated: May 10, 2025

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Published on: November 27, 2015

Síntesis Total Estereoselectiva de Nimbolida

David B Ryffel^1,2, Peter C Ryffel², Matteo Martinelli³

¹Department of Chemistry, Rice University, Houston, Texas 77005, United States.

Journal of the American Chemical Society

|April 21, 2025

Resumen

Este estudio presenta una nueva síntesis total estereoselectiva de 11 pasos de nimbolida. Los pasos clave incluyen la ciclización de Heck borilativa catalizada por paladio y la eterificación estereoretativa para una síntesis eficiente.

Área de la Ciencia:

Química orgánica
Química sintética
Química medicinal

Sus antecedentes:

Nimbolide es un producto natural bioactivo con aplicaciones terapéuticas potenciales.
La síntesis eficiente y estereoselectiva de productos naturales complejos es crucial para la investigación biológica y el desarrollo de fármacos.

Objetivo del estudio:

Desarrollar una síntesis total de nimbolida concisa y estereoselectiva.
Para establecer una ruta sintética escalable para la producción de nimbolida.

Principales métodos:

Estrategia de síntesis convergente que utiliza el α-metil-R) -carvón como material de partida.
Las reacciones clave incluyen la ciclización de Heck borilativa catalizada por paladio para la construcción de anillos A y la oxidación de C28.
Eterificación estereorretente para el acoplamiento de fragmentos y la formación de enlaces C-O.
Ciclización radicalizada regioselectiva y lactonización en etapa tardía para la formación del producto final.

Principales resultados:

Se logró una síntesis total estereoselectiva de nimbolida en una secuencia de 11 pasos.
Construido con éxito el núcleo de nimbolido, incluida la fracción de decalina, con alto control estereoquímico.
Escalabilidad demostrada para los productos intermedios clave y el proceso sintético en general.

Conclusiones:

La vía sintética desarrollada proporciona un método eficiente y escalable para la nimbolida.
Esta síntesis abre caminos para explorar las propiedades farmacológicas de la nimbolida y sus posibles usos terapéuticos.

Más Videos Relacionados

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

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

Published on: June 13, 2022

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

Videos de Conceptos Relacionados

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.

Regioselectivity and Stereochemistry of Hydroboration

Regioselectivity and Stereochemistry of Hydroboration

A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...

SN2 Reaction: Stereochemistry

S_N2 Reaction: Stereochemistry

In an SN2 reaction, the nucleophilic attack on the substrate and departure of the leaving group occurs simultaneously through a transition state. As the nucleophile approaches the substrate from the back-side, the configuration of the substrate carbon changes from tetrahedral to trigonal bipyramidal and then back to tetrahedral, leading to an inversion in the configuration of the product.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not...

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

Diels–Alder Reaction Forming Cyclic Products: Stereochemistry

The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.

SN1 Reaction: Stereochemistry

S_N1 Reaction: Stereochemistry

This lesson provides an in-depth discussion of the stereochemical outcomes in an SN1 reaction.
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...

Prochirality

Prochirality

The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...