[EN] PROCESS FOR THE PREPARATION OF ( S ) - 3 - CYANO - 5 - METHYLHEXANOIC ACID DERIVATIVES ADN OF PREGABALIN [FR] PROCÉDÉ DE PRÉPARATION DE DÉRIVÉS D'ACIDE (S)-3-CYANO-5-MÉTHYLHEXANOÏQUE ET DE PRÉGABALINE
[EN] PROCESS FOR THE PREPARATION OF ( S ) - 3 - CYANO - 5 - METHYLHEXANOIC ACID DERIVATIVES ADN OF PREGABALIN [FR] PROCÉDÉ DE PRÉPARATION DE DÉRIVÉS D'ACIDE (S)-3-CYANO-5-MÉTHYLHEXANOÏQUE ET DE PRÉGABALINE
Palladium-Catalyzed Elimination/Isomerization of Enol Triflates into 1,3-Dienes
作者:Ian T. Crouch、Timothy Dreier、Doug E. Frantz
DOI:10.1002/anie.201101820
日期:2011.6.27
were synthesized by the title reaction (see scheme; Tf=trifluoromethanesulfonyl). Preliminary studies support a mechanistically distinct pathway that involves an initial β‐hydride elimination from a cationic vinyl palladium(II) intermediate, a subsequent regiospecific hydropalladation of the corresponding allene intermediate, and a final β‐hydride elimination.
Screening of a Combinatorial Homing Peptide Library for Selective Cellular Delivery
作者:Nina Svensen、Juan José Díaz-Mochón、Kevin Dhaliwal、Songsak Planonth、Michael Dewar、J. Douglas Armstrong、Mark Bradley
DOI:10.1002/anie.201101804
日期:2011.6.27
To the point: The identification of peptides to optimize both the delivery and tumor penetration of existing cancer drugs in a cell‐selective manner would be highly desirable. The screening of a peptide nucleic acid (PNA)‐encoded peptidelibrary (see picture) now allows the identification of versatile cell homingpeptides for any cell type of interest.
Chemoenzymatic Asymmetric Synthesis of Pregabalin Precursors via Asymmetric Bioreduction of β-Cyanoacrylate Esters Using Ene-Reductases
作者:Christoph K. Winkler、Dorina Clay、Simon Davies、Pat O’Neill、Paul McDaid、Sebastien Debarge、Jeremy Steflik、Mike Karmilowicz、John W. Wong、Kurt Faber
DOI:10.1021/jo302484p
日期:2013.2.15
The asymmetric bioreduction of a library of beta-cyanoacrylate esters using ene-reductases was studied with the aim to provide a biocatalytic route to precursors for GABA analogues, such as pregabalin. The stereochemical outcome could be controlled by substrate-engineering through size-variation of the ester moiety and by employing stereochemically pure (E)- or (Z)-isomers, which allowed to access both enantiomers of each product in up to quantitative conversion in enantiomerically pure form. In addition, stereoselectivities and conversions could be improved by mutant variants of OPR1, and the utility of the system was demonstrated by preparative-scale applications.
Evaluation of Several Routes to Advanced Pregabalin Intermediates: Synthesis and Enantioselective Enzymatic Reduction Using Ene-Reductases
This publication describes the evaluation of four synthetic routes to the advanced pregabalin (Lyrica) intermediate 7. Asymmetric reduction of (E)-7 with an ene-reductase (OPR1 from Lycopersicon esculentum) gave a saturated cyanoester intermediate 5 with the desired S stereocenter in >99% ee. OPR1 also catalyzed the reduction of (Z)-7 to (S)-5, but with lower conversion and selectivity.