This invention provides novel 1,4-di-substituted piperidine derivatives of the general formula \x9bI! ##STR1## and the pharmaceutically acceptable salts thereof, wherein: Ar represents a phenyl group or a five- or six-membered heteroaromatic group having one or two hetero atoms selected from the group consisting of an oxygen atom, a sulfur atom and a nitrogen atom in which one or two optional hydrogen atoms on the ring may be replaced by substituent groups selected from the group consisting of a halogen atom and a lower alkyl group; R.sup.1 represents a cycloalkyl group of 3 to 6 carbon atoms or a cycloalkenyl group of 3 to 6 carbon atoms; R.sup.2 represents a saturated or unsaturated aliphatic hydrocarbon radical of 5 to 15 carbon atoms; and X represents O or NH. These compounds have selective antagonistic activity against the muscarinic M.sub.3 receptors and can hence be used safely with a minimum of side effects.
Direct Synthesis of <i>N</i>-Alkyl Arylglycines by Organocatalytic Asymmetric Transfer Hydrogenation of <i>N</i>-Alkyl Aryl Imino Esters
作者:Javier Mazuela、Thomas Antonsson、Magnus J. Johansson、Laurent Knerr、Stephen P. Marsden
DOI:10.1021/acs.orglett.7b02627
日期:2017.10.20
The organocatalytic asymmetrictransferhydrogenation of N-alkyl aryl imino esters for the direct synthesis of N-alkylated arylglycinate esters is reported. High yields and enantiomeric ratios were obtained, and tolerance to a diverse set of functional groups facilitated the preparation of more complex molecules as well as intermediates for active pharmaceuticals. A simple recycling protocol was developed