Enantioselective Syntheses of (-)-(<i>R</i>)-Rolipram, (-)-(<i>R</i>)-Baclofen and Other GABA Analogues via Rhodium-Catalyzed Conjugate Addition of Arylboronic Acids
作者:Günter Helmchen、Jean-Michel Becht、Oliver Meyer
DOI:10.1055/s-2003-42457
日期:——
Highly enantioselective syntheses of two important γ-aminobutyric acid (GABA) analogues, the antispastic drug (-)-(R)-Baclofen and the antidepressant agent (-)-(R)-Rolipram, are reported. Key-steps in both syntheses are the Rh-catalyzed asymmetric 1,4-additions of arylboronic acids to 4-aminobut-2,3-enoic acid derivatives.
HClO<sub>4</sub>·SiO<sub>2</sub>-mediated Improved Isomerization of Glycidic Esters to α-Hydroxy-β,γ-unsaturated Esters: Application in the Formal Synthesis of (<i>R</i>)-Baclofen and β-Phenyl GABA Analogues
作者:Ranjan Basak、Suresh Dharuman、Y. Suman Reddy、Venkata Ramana Doddi、Yashwant D. Vankar
DOI:10.1246/cl.2012.325
日期:2012.3.5
An efficient isomerization of glycidic esters to corresponding allylic alcohols, viz. α-hydroxy-β,γ-unsaturated esters has been brought about using HClO4·SiO2. Five of these allylic alcohols underw...