Synthesis of bridged piperazines with σ receptor affinity
作者:Manuela Weigl、Bernhard Wünsch
DOI:10.1016/j.ejmech.2007.02.005
日期:2007.10
from (S)-glutamate, which was transformed in five reaction steps into the piperazinediones 5 bearing a propionic acid ester side chain. A two-step Dieckmann analogous cyclization provided the bicyclic ketones 7 as key intermediates. The alcohols 8 were prepared by LiAlH4 reduction of the ketones 7. NaBH4 reduction, Williamson ether synthesis and LiAlH4 reduction led to the methyl and benzyl ethers 12
Conformationally constrained ethylenediamines: synthesis and receptor binding of 6,8-Diazabicyclo[3.2.2]nonanes
作者:Manuela Weigl、Stephan Bedürftig、Christoph A Maier、Bernhard Wünsch
DOI:10.1016/s0968-0896(02)00043-3
日期:2002.7
The synthesis and receptor affinity of 6,8-diazabicyclo[3.2.2]nonanes representing conformationallyconstrained ethylenediamines are described. The Dieckmann analogous cyclization of the (piperazin-2-yl)propionate 9 provided the bicyclononane 10 only, when the first cyclization product was trapped with chlorotrimethylsilane. 10 was stereoselectively transformed into the bicyclic amines 19a,b and amides