Chiral Pyrroline-Based Ugi-Three-Component Reactions Are under Kinetic Control
作者:Erwin R. van Rijssel、Theodorus P. M. Goumans、Gerrit Lodder、Herman S. Overkleeft、Gijsbert A. van der Marel、Jeroen D. C. Codée
DOI:10.1021/ol4012053
日期:2013.6.21
is often assumed that the stereochemistry in Ugi multicomponent reactions is determined in the final Mumm rearrangement step, experimental and computational evidence that Ugi reactions on hydroxylated pyrrolines proceed under kinetic control is reported. The stereochemistry of the reaction is established with the addition of the isocyanide to the intermediate iminium ion, whose conformation is determined
A synthesis of (+)-7-Epiaustraline and (−)-7-Epialexine
作者:William H. Pearson、Jennifer V. Hines
DOI:10.1016/0040-4039(91)80071-d
日期:1991.9
Reductive cyclization of the azido epoxides 19-alpha and 19-beta followed by deprotection afforded the HIV inhibitor (+)-7-epiaustraline 7 and (-)-7-epialexine 9. The formation of 7 proceeded with an unusual inversion of configuration at C-7.