Opposite Enantioselectivity in the Bioreduction of (<i>Z</i>
)-β-Aryl-β-cyanoacrylates Mediated by the Tryptophan 116 Mutants of Old Yellow Enzyme 1: Synthetic Approach to (<i>R</i>
)- and (<i>S</i>
)-β-Aryl-γ-lactams
作者:Elisabetta Brenna、Michele Crotti、Francesco G. Gatti、Daniela Monti、Fabio Parmeggiani、Robert W. Powell、Sara Santangelo、Jon D. Stewart
DOI:10.1002/adsc.201500206
日期:2015.5.26
The Trp 116mutants of OldYellowEnzyme1 that catalyse the reduction of (Z)‐β‐aryl‐β‐cyanoacrylates give the oppositeenantioselectivity according to the nature of the amino acid in position 116. Small amino acids (e.g., alanine) make the substrate bind to the enzyme′s active site in a “classical” orientation, affording the (S)‐enantiomer of the reduced product. When the size of the amino acid increases
Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical aniongeneration approaches. Precise control over the chemo- and stereoselectivity
A number of nitrile-containing chiral molecules were synthesized via asymmetric nucleophilic addition of formaldehyde N,N-dialkylhydrazone as the nitrile equivalent. Chiral N,N′-dioxide/metal salt complexes enabled the asymmetric addition reactions to both isatin-derived imines and α,β-unsaturated ketones, generating amino nitriles and 4-oxobutanenitrile derivatives in good yields with high enantioselectivities
A short, chemoenzymatic route to chiral β-aryl-γ-amino acids using reductases from anaerobic bacteria
作者:Anna Fryszkowska、Karl Fisher、John M. Gardiner、Gill M. Stephens
DOI:10.1039/b919526b
日期:——
A short chemoenzymatic synthesis of β-aryl-γ-aminobutyric acids has been developed, based on a highly enantioselective biocatalytic reduction of β-aryl-β-cyano-α,β-unsaturated carboxylic acids.