作者:Roger R. Hill、David Birch、Graham E. Jeffs、Michael North
DOI:10.1039/b211914e
日期:2003.3.13
Selectivity in abiotic condensations of amino acids remains controversial and stereochemically little explored. We find that competitive activated couplings of N-acyl derivatives of glycine, alanine, valine, proline and phenylalanine with binary, ternary and quaternary mixtures of amides and esters of the same group of amino acids show little selectivity among the reactants, except with respect to configuration, where a consistent and significant preference for heterochiral outcomes, mostly >80%, is observed. One possible explanation of this selectivity predicts a predisposition to homochiral coupling under conditions that would require the two carboxyl functions to be co-facial in the activated complex.
[EN] METHODS OF TREATING ALZHEIMER'S DISEASE USING AROMATICALLY SUBSTITUTED omega-AMINO-ALKANOIC ACID AMIDES AND ALKANOIC ACID DIAMIDES<br/>[FR] METHODES DE TRAITEMENT DE LA MALADIE D'ALZHEIMER AU MOYEN D'AMIDES D'ACIDE O-AMINO-ALCANOIQUE A SUBSTITUTIONS AROMATIQUES ET DE DIAMIDES D'ACIDE ALCANOIQUE
申请人:ELAN PHARM INC
公开号:WO2003103652A1
公开(公告)日:2003-12-18
Disclosed.are methods for treating Alzheimer's disease, and other diseases,
and/or inhibiting beta-secretase enzyme, and/or inhibiting deposition of
A beta peptide in a mammal, by use of compounds of formula (I) wherein the variables
R1, R2, R3, R4, R5, X1,
and X2 are defined herein.
An unprecedented Ru-catalyzed directasymmetric reductive amination of α-keto amides with ammonium salts has been achieved. This protocol provides an efficient and practical way for the synthesis of diverse enantioenriched α-aryl- or alkyl-substituted N-unprotected unnatural α-amino acids and N-unprotected β-branched α-amino acids. Further follow-up transformations enable access to drug intermediates