205264-82-0Relevant academic research and scientific papers
Rh-DuPHOS-catalyzed enantioselective hydrogenation of enol esters. Application to the synthesis of highly enantioenriched α-hydroxy esters and 1,2-diols
Burk, Mark J.,Kalberg, Christopher S.,Pizzano, Antonio
, p. 4345 - 4353 (1998)
The asymmetric hydrogenation of α-(acetyloxy)- and α- (benzoyloxy)acrylates 4 catalyzed by cationic rhodium-DuPHOS complexes has been examined. A wide range of substrates (4) were prepared via a convenient Horner-Emmons condensation protocol, and subsequently hydrogenated under mild conditions (60 psi of H2) at substrate-to-catalyst ratios (S/C) of 500. Overall, enol ester substrates 4 were reduced by the cationic Et-DuPHOS-Rh catalysts with very high levels of enantioselectivity (93-99% ee). Importantly, substrates 4 bearing β-substituents could be employed as E/Z isomeric mixtures with no detrimental effect on the selectivity. Labeling studies indicated that no significant E/Z isomerization of the substrates occurs during the course of these reactions. Details concerning optimization of the reaction, interesting solvent effects, and deprotection procedures for the synthesis of highly enantioenriched α-hydroxy esters and 1,2-diols also are provided.
Novel therapeutic agents for the treatment of migraine
-
Page/Page column 29-30, (2010/02/14)
The present invention relates to compounds of Formula (I) as antagonists of calcitonin gene-related peptide receptors (“CGRP-receptor”), pharmaceutical compositions comprising them, methods for identifying them, methods of treatment using them and their u
