6813-61-2Relevant academic research and scientific papers
Transformation of Racemic Azlactones into Enantioenriched Dihydropyrroles and Lactones Enabled by Hydrogen-Bond Organocatalysis
?abka, Matej,Kocian, Adrián,Bilka, Stanislav,Andrej?ák, Samuel,?ebesta, Radovan
, p. 6077 - 6087 (2019/09/12)
Azlactones, a potent building block for the synthesis of complex molecules, have been explored in an organocatalytic Mannich reaction with protected imines. In this study, azlactones containing a propargyl substituent were employed for the first time in organocatalysis so far. The catalytically active species responsible for high enantioselectivity with substrate containing such a small linear substituent is assembled in situ from a bifunctional thiourea, prone to dimerization, and an organic acid, as evidenced by DOSY NMR. The resulting α,β-diamino acid derivatives were subjected to further derivatization: as an example, gold-catalyzed intramolecular hydroamination of alkynes gave chiral spirocyclic dihydropyrrole. Alternatively, related squaramide catalyst enabled a Mannich reaction of azlactones with N-aryl or alkyl glyoxylate imines. Reduction of these adducts gave access to 2,3-diaminobutyrolactones or 2,3-diamino-1,4-diol with a tertiary and a quaternary stereocenter.
Polyclonal antibodies: A cheap and efficient tool for screening of enantioselective catalysts
MacOvei, Cristian,Vicennati, Paola,Quinton, Julia,Nevers, Marie-Claire,Volland, Herve,Creminon, Christophe,Taran, Frederic
supporting information; experimental part, p. 4411 - 4413 (2012/05/20)
Enantioselective polyclonal antibodies have been produced and characterized to develop a high-throughput screening method for lipase activity fingerprinting, with a view to the enantioselective hydrolysis of azlactones.
