The one-pot N-demethylation and acid-catalyzedrearrangement of morphinan-N-oxides offers a new, shorter and more efficient route to neuropharmacologically important N-substituted aporphines. An improved procedure is described for the preparation of the starting alkaloid N-oxides using Na2WO4 as catalyst. The transetherification during the rearrangement of codeinone into 2-O-alkyl-norapocodeines is
一锅N-去甲基化和吗啡喃-N-氧化物的酸催化重排提供了一条新的,更短且更有效的途径来获得神经药理学上重要的N-取代的紫杉醇。描述了使用Na 2 WO 4作为催化剂制备起始生物碱N-氧化物的改进方法。记录了可待因酮重排成2 - O-烷基-诺拉普可待因期间的酯交换作用。
Efficient N-Demethylation of Opiate Alkaloids Using a Modified Nonclassical Polonovski Reaction
作者:Kristy McCamley、Justin A. Ripper、Robert D. Singer、Peter J. Scammells
DOI:10.1021/jo035243z
日期:2003.12.1
A modified Polonovskireaction has been employed to N-demethylate several opiate alkaloids in moderate to high yield. This method provides an alternative to traditional N-demethylation procedures which utilize toxic reagents such as cyanogen bromide or expensive reagents such as vinyl chloroformate. The current synthesis involves N-oxide formation, isolation of the corresponding N-oxide hydrochloride
[EN] PROCESS FOR THE SYNTHESIS OF N-DEMETHYLATED MORPHINANE COMPOUNDS<br/>[FR] PROCÉDÉ DE SYNTHÈSE DE COMPOSÉS MORPHINANES N-DÉMÉTHYLÉS
申请人:TPI ENTPR PTY LTD
公开号:WO2009152577A1
公开(公告)日:2009-12-23
The present invention relates to a process for the preparation of an N-demethyl morphinane or a protected form thereof. In one form the preparation of the N-demethyl morphinane or a protected form thereof involves the N-demethylation of an N-methyl morphinane or protected form thereof. In particular the present process is useful in the preparation N-demethyl morphinane or a protected form thereof by N-demethylation of N-methyl morphinanes or protected forms thereof extracted from plants of the genus Papaver of the family Papaveraceae. An example of a suitable N-methyl morphinane that may be usefully subjected to the process of the present invention is thebaine.
New Methodology for the N-Demethylation of Opiate Alkaloids
作者:Zemin Dong、Peter J. Scammells
DOI:10.1021/jo071171q
日期:2007.12.1
N-Demethylation is a key step in the preparation of a number of semisynthetic opiate pharmaceuticals. Herein we report a high-yielding, catalytic procedure for the N-demethylation of opiates which has a number of advantages over existing methods. For example, tetrasodium 5,10,15,20-tetra(4-sulfophenyl)porphyrinatoiron(II) (0.3 molar equiv) effected the transformation of codeine methyl ether to the corresponding N-nor analogue in 91% yield. The catalyst was readily removed and recycled.