957770-66-0Relevant articles and documents
Catalytic atroposelective dynamic kinetic resolutions and kinetic resolutions towards 3-arylquinolinesviaSNAr
Cardenas, Mariel M.,Saputra, Mirza A.,Gordon, Deane A.,Sanchez, Andrea N.,Yamamoto, Nobuyuki,Gustafson, Jeffrey L.
supporting information, p. 10087 - 10090 (2021/10/06)
Herein we report the catalytic atroposelective syntheses of pharmaceutically relevant 3-arylquinolinesviathe nucleophilic aromatic substitution (SNAr) of thiophenols into 3-aryl-2-fluoroquinolines mediated by catalytic amounts of Cinchona alkaloid-derived ureas. These reactions displayed a spectrum of dynamic kinetic resolution (DKR) and kinetic resolution (KR) characters depending upon the stereochemical stability of the starting material. Low barrier substrates proceededviaDKR while higher barrier substrates proceededviaKR. On the other hand, substrates with intermediate stabilities displayed hallmarks of both DKR and KR. Finally, we also show that we can functionalize the atropisomerically enriched quinolines into pharmaceutically privileged scaffolds with minimal observed racemization.
Catalytic Asymmetric Synthesis of Quaternary Barbituric Acids
Del Pozo, Sandra,Vera, Silvia,Oiarbide, Mikel,Palomo, Claudio
, p. 15308 - 15311 (2017/11/06)
The catalytic asymmetric α-functionalization of prochiral barbituric acids, a subtype of pseudosymmetric 1,3-diamides, to yield the corresponding 5,5-disubstituted (quaternary) derivatives remains essentially unsolved. In this study 2-alkylthio-4,6-dioxopirimidines are designed as key 1,3-diamide surrogates that perform exceedingly in amine-squaramide catalyzed C-C bond forming reactions with vinyl ketones or Morita-Baylis-Hillmann-type allyl bromides as electrophiles. Mild acid hydrolysis of adducts affords barbituric acid derivatives with an in-ring quaternary carbon in unprecedented enantioselectivity, offering valuable materials for biological evaluations.
Stereoselective glycosylation of 2-nitrogalactals catalyzed by a bifunctional organocatalyst
Medina, Sandra,Harper, Matthew J.,Balmond, Edward I.,Miranda, Silvia,Crisenza, Giacomo E. M.,Coe, Diane M.,McGarrigle, Eoghan M.,Galan, M. Carmen
supporting information, p. 4222 - 4225 (2016/09/09)
The use of a bifunctional cinchona/thiourea organocatalyst for the direct and α-stereoselective glycosylation of 2-nitrogalactals is demonstrated for the first time. The conditions are mild, practical, and applicable to a wide range of glycoside acceptors with products being isolated in good to excellent yields. The method is exemplified in the synthesis of mucin type Core 6 and 7 glycopeptides.