A novel enantioselective organocatalytic strategy is presented for the synthesis of tetrahydrofurobenzofuran and methanobenzodioxepine naturalproductcorestructures. The strategy is based on a pair of divergent reaction pathways in which hydroxyarenes react with γ‐keto‐α,β‐unsaturated aldehydes, catalyzed by a chiral secondary amine. One reaction pathway, which leads to chiral 5,5‐fused acetals with
Synthesis of trifluoromethyl-/cyclopropyl-substituted 2-isoxazolines by DBU-promoted domino reaction
作者:Xiao-Dong Liu、Hai-Yan Ma、Chun-Hui Xing、Long Lu
DOI:10.1016/j.cclet.2017.03.031
日期:2017.8
cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5- trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method
properly activated by electron-withdrawing groups on both ends, are shown to be suitable substrates for phosphine-promoted organocatalytic processes. Their reactions with imines, under phosphine catalysis, afford a new and efficient synthetic approach to functionalized 3-pyrrolines.
An efficient transition-metal-free hydrodefluorination reaction of trifluoromethyl alkenes for accessing gem-difluoroalkenes is developed. It was surprising to find that the phosphoryl anion is able to mediate the defluorination.
[EN] SUBSTITUTED POLYCYCLIC ARYL AND HETEROARYL PYRAZINONES USEFUL FOR SELECTIVE INHIBITION OF THE COAGULATION CASCADE<br/>[FR] ARYLE POLYCYCLIQUE SUBSTITUTE ET PYRAZINONES D'HETEROARYLE UTILISES DANS L'INHIBITION SELECTIVE DE LA COAGULATION
申请人:PHARMACIA CORP
公开号:WO2001087854A1
公开(公告)日:2001-11-22
The invention relates to substituted polycyclic aryl and heteroaryl pyrazinone compounds useful as inhibitors of serine proteases of the coagulation cascade and compounds, compositions and methods for anticoagulant therapy for the treatment and prevention of a variety of thrombotic conditions including coronary artery and cerebrovascular diseases.