Video Experimental Relacionado
Updated: Jun 19, 2026
11:45
Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Síntesis total y determinación de la configuración absoluta de la frondosina B
M Inoue1, M W Carson, A J Frontier
1Laboratory for Bioorganic Chemistry, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, NY 10021, USA.
Journal of the American Chemical Society
|July 18, 2001
Resumen
Se desarrollaron dos nuevas síntesis de frondosina B, un antagonista del receptor de la interleucina-8. Estas rutas establecen la configuración absoluta de la frondosina B, confirmando la configuración R en el centro metilo secundario.
Área de la Ciencia:
- Síntesis orgánica La síntesis orgánica.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
Sus antecedentes:
- La frondosina B es un antagonista del receptor de la interleucina-8.
- Desarrollar rutas sintéticas eficientes es crucial para el descubrimiento y desarrollo de fármacos.
Objetivo del estudio:
- Para lograr una síntesis total concisa de (+/-) -frondosina B.
- Para determinar la configuración absoluta de la frondosina B.
Principales métodos:
- Reacción clásica de Friedel-Crafts para formar un anillo de siete miembros.
- Ciclización catiónica y reacciones de Diels-Alder para la construcción de anillos carbocíclicos.
- Síntesis enantioselectiva para establecer una configuración absoluta.
Principales resultados:
- Se establecieron con éxito dos rutas sintéticas distintas para la frondosina B a partir del 5-metoxisalicilaldehído.
- El enfoque de Diels-Alder controlaba efectivamente el posicionamiento de bonos dobles.
- Una tercera síntesis enantioselectiva confirmó la configuración R en el centro metilo secundario.
Conclusiones:
- La configuración absoluta del centro metilo secundario en la frondosina B es R.
- Estas síntesis proporcionan información valiosa sobre la construcción de la estructura del núcleo de la frondosina B.
Videos de Conceptos Relacionados
02:18Fischer Projections
Learning to draw Fischer projections of molecules and understanding their relevance plays a crucial role in the visual depiction of organic molecules. A Fischer projection is a two-dimensional projection on a planar surface to simplify the three-dimensional wedge–dash representation of molecules. This is especially helpful in the case of molecules with multiple chiral centers that can be difficult to draw. Here, all the bonds of interest are represented as horizontal or vertical lines. While...
01:07Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
01:18Frost Circles for Different Conjugated Systems
The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.
01:15Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations
Gentamicin, an aminoglycoside antibiotic, is commonly administered via intermittent intravenous infusion to treat severe infections. An intermittent one-hour infusion of gentamicin, administered at eight-hour intervals, allows for precise control of plasma drug concentrations, minimizing toxicity while ensuring therapeutic efficacy. Pharmacokinetic principles govern the dynamics of plasma concentrations and can be mathematically described using specific equations.The plasma drug concentration...
01:15Antifungal Agents
Amphotericin B is a broad-spectrum antifungal agent that exploits structural differences between fungal and mammalian cell membranes. Its amphipathic structure—featuring a hydrophobic polyene-lactone ring and a hydrophilic region containing mycosamine and carboxylic acid groups—enables selective binding to ergosterol, a sterol predominantly found in fungal plasma membranes. This selective interaction underlies the drug’s antifungal activity, although weak binding to cholesterol contributes to...