51318-62-8Relevant articles and documents
N-Heterocyclic Carbene-Catalyzed Enantioselective Intramolecular Annulations to Construct Benzo-Fused Pyranones with Quaternary Stereocenter
Dzieszkowski, Krzysztof,Rafiński, Zbigniew
, p. 3830 - 3835 (2020)
A highly enantioselective intramolecular NHC-catalyzed approach for the synthesis of benzo-fused pyranones bearing quaternary stereocenter is described. The developed methodology is based on annulation reaction between acyl anion intermediates and β,β-disubstituted Michael acceptors. The reaction offers streamlined and effective access to target products in a highly stereoselective manner. (Figure presented.).
COMPOUNDS AND SYNTHETIC METHODS FOR THE PREPARATION OF RETINOID X RECEPTOR-SPECIFIC RETINOIDS
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Paragraph 191-194, (2019/06/05)
Provided herein are compounds useful for the preparation of compounds that have retinoid-like biological activity. Also provided herein are processes for the preparation of compounds that have retinoid-like biological activity.
Asymmetric Reductive Carbocyclization Using Engineered Ene Reductases
Heckenbichler, Kathrin,Schweiger, Anna,Brandner, Lea Alexandra,Binter, Alexandra,Toplak, Marina,Macheroux, Peter,Gruber, Karl,Breinbauer, Rolf
supporting information, p. 7240 - 7244 (2018/06/15)
Ene reductases from the Old Yellow Enzyme (OYE) family reduce the C=C double bond in α,β-unsaturated compounds bearing an electron-withdrawing group, for example, a carbonyl group. This asymmetric reduction has been exploited for biocatalysis. Going beyond its canonical function, we show that members of this enzyme family can also catalyze the formation of C?C bonds. α,β-Unsaturated aldehydes and ketones containing an additional electrophilic group undergo reductive cyclization. Mechanistically, the two-electron-reduced enzyme cofactor FMN delivers a hydride to generate an enolate intermediate, which reacts with the internal electrophile. Single-site replacement of a crucial Tyr residue with a non-protic Phe or Trp favored the cyclization over the natural reduction reaction. The new transformation enabled the enantioselective synthesis of chiral cyclopropanes in up to >99 % ee.
