Conjugate Additions to Phenylglycinol-Derived Unsaturated δ-Lactams. Enantioselective Synthesis of Uleine Alkaloids
作者:Mercedes Amat、Maria Pérez、Núria Llor、Carmen Escolano、F. Javier Luque、Elies Molins、Joan Bosch
DOI:10.1021/jo0487101
日期:2004.12.1
sulfur-stabilized anions) to the phenylglycinol-derived unsaturated lactams trans-2, cis-2, and its 8-ethyl-substituted analogue 10 is studied. The factors governing the exo or endo facial stereoselectivity are discussed. This methodology provides short synthetic routes to either cis- or trans-3,4-disubstituted enantiopure piperidines as well as efficient routes for the enantioselective construction of the tetracyclic
A practical procedure for the removal of the phenylethanol moiety from phenylglycinol-derived lactams
作者:Vladislav Semak、Carmen Escolano、Carlos Arróniz、Joan Bosch、Mercedes Amat
DOI:10.1016/j.tetasy.2010.09.014
日期:2010.10
Chiral non-racemic bicyclic lactams derived from phenylglycinol have been appointed as key building blocks for the preparation of enantiopure nitrogen compounds The removal of the chiral inductor leading to substituted piperidones by using air or oxygen in basic media is presented (C) 2010 Elsevier Ltd All rights reserved
Enantioselective formal synthesis of uleine alkaloids from phenylglycinol-derived bicyclic lactams
two-step route for the enantioselective construction of the tetracyclic ring system of uleine alkaloids, involving the stereoselective conjugate addition of an appropriate indole-containing nucleophile to a chiral bicyclic delta-lactam and the subsequent cyclization on the indole 3-position of the resulting 4,5-disubstituted 2-piperidone, has culminated in the formal total synthesis of several alkaloids
Asymmetric Total Syntheses of Rhynchophylline and Isorhynchophylline
作者:Zhihong Zhang、Wei Zhang、Fangyuan Kang、Fanny C. F. Ip、Nancy Y. Ip、Rongbiao Tong
DOI:10.1021/acs.joc.9b01977
日期:2019.9.6
The asymmetrictotalsyntheses of (−)-rhynchophylline and (+)-isorhynchophylline were achieved in 17 and 16 steps, respectively, from butanal and ethyl acrylate. Our synthesis features Carreira ring expansion to construct the tetracyclic spirooxindole core in high diastereoselectivity and the use of Bosch’s chiral lactam for preparation of enantioenriched cyclic imine.