Cyanomethyl anion transfer reagents for diastereoselective Corey–Chaykovsky cyclopropanation reactions
作者:Renè Hommelsheim、Katharina J. Hock、Christian Schumacher、Mohanad A. Hussein、Thanh V. Nguyen、Rene M. Koenigs
DOI:10.1039/c8cc05602a
日期:——
A readily available and bench-stable cyanomethyl sulfonium salt was used in highly diastereoselective Corey–Chaykovsky cyclopropanationreactions of electron-poor olefins. This efficient method provides a rapid route to access densely functionalized cyclopropyl nitriles.
Design, Synthesis, and Biological Evaluation of New Inhibitors of the Endocannabinoid Uptake: Comparison with Effects on Fatty Acid Amidohydrolase
作者:María L. López-Rodríguez、Alma Viso、Silvia Ortega-Gutiérrez、Christopher J. Fowler、Gunnar Tiger、Eva de Lago、Javier Fernández-Ruiz、José A. Ramos
DOI:10.1021/jm0210818
日期:2003.4.1
A new series of arachidonic acid derivatives were synthesized and evaluated as inhibitors of the endocannabinoiduptake. Most of them are able to inhibit anandamide uptake with IC(50) values in the low micromolar range (IC(50) = 0.8-24 microM). In general, the compounds had only weak effects upon CB(1), CB(2), and VR(1) receptors (K(i) > 1000-10000 nM). In addition, there was no obvious relationship
A novelbifunctional organocatalyst library combining both aminocatalysis and phosphonicacid activation was used for the first time as an efficient tool for the stereoselectiveMichaeladdition of aldehydes with several aromatic nitroalkenes with good selectivities up to 95:5 dr and 93:7 er. Due to their high water solubility, the catalysts were easilyrecyclable and could be reused over several cycles
Novel thiourea-amine bifunctional catalysts for asymmetric conjugate addition of ketones/aldehydes to nitroalkenes: rational structural combination for high catalytic efficiency
A series of thiourea-amine bifunctionalcatalysts have been developed by a rational combination of prolines with cinchona alkaloids, which are connected by a thiourea motif. The catalyst 3a, prepared from L-proline and cinchonidine, was found to be a highly efficient catalyst for the conjugateaddition of ketones/aldehydes to a wide range of nitroalkenes (up to 98/2 dr and 96% ee). The privileged cinchonidine
Highly enantio- and diastereoselective Michael addition of cyclohexanone to nitroolefins catalyzed by a chiral glucose-based bifunctional secondary amine-thiourea catalyst
A novel bifunctional thiourea bearing a saccharide-scaffold and a secondary amino group was synthesized, and was proven to be an effective organocatalyst for the asymmetric Michael reaction of cyclohexanone to both aryl and alkyl nitroolefins. The corresponding adducts were obtained with excellent diastereo- (up to >99/1 dr) and enantioselectivities (up to 97% ee).