A bifunctional squaramide-catalyzed reaction of azlactones and o-quinone methides in situ generatedfrom 2-(1-tosylalkyl)-phenols has been succesfully developed under basic condition, providing an efficient and mild access to chiral dihydrocoumarins...
SITE-SPECIFIC INCORPORATION OF FLUORINATED AMINO ACIDS INTO PROTEINS
申请人:Mehl A. Ryan
公开号:US20070218483A1
公开(公告)日:2007-09-20
This invention relates, in part, to newly identified polynucleotides, polypeptides, variants and derivatives thereof; processes for making the polynucleotides and the polypeptides, and their variants and derivatives; and uses of the polynucleotides, polypeptides, variants and derivatives. The invention also relates to compositions of orthogonal aminoacyl-tRNA synthetases, and pairs of orthogonal aminoacyl-tRNA synthetases, and orthogonal tRNAs that incorporate fluorinated amino acids into proteins in response to selector codons. The present invention also includes translation biochemistry methods for site-specific incorporation of fluorinated amino acids, for example,
18
F- or
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F-labelled amino acids, into proteins or peptides. Such amino acids may be used as an NMR probe for characterizing protein structure, dynamics, and reactivity or for radionuclide imaging (e.g., PET). Fluorinated amino acids may also be used to stabilize proteins or peptides.
pyrrolidine-catalyzed three-component reaction of azlactone, N,O-acetal and alcohol for the synthesis of α,β-diamino ester was reported. The N,O-acetal served as the imine equivalent to occur Mannich reaction with azlactone, and the in situ generated α-functionalized azlactone subsequently underwent a ring-opening process in the presence of alcohol. A series of α,β-diamino esters were obtained in 36–99% yields