Asymmetric Construction of Remote Vicinal Quaternary and Tertiary Stereocenters via Direct Doubly Vinylogous Michael Addition
作者:Subhrajit Rout、Harshit Joshi、Vinod K. Singh
DOI:10.1021/acs.orglett.8b00493
日期:2018.4.20
An asymmetric direct doubly vinylogousMichaeladdition has been developed for the generation of sterically congested vicinal quaternary and tertiary stereocenters. This doubly vinylogousMichaeladdition of β,γ-unsaturated butenolides to 3-methyl-4-nitro-5-alkenyl isoxazoles, powered by a bifunctional squaramide, affords a broad range of densely functionalized enantioenriched γ,γ-disubstituted butenolides
Phase transfer catalyzed enantioselective cyclopropanation of 4-nitro-5-styrylisoxazoles
作者:Claudia Del Fiandra、Linda Piras、Francesco Fini、Paolo Disetti、Maria Moccia、Mauro F. A. Adamo
DOI:10.1039/c2cc30401e
日期:——
substituted cyclopropane esters were prepared in high yields, complete diastereoselection and high (up to 96%) enantioselectivity. The reaction described herein entailed reacting 4-nitro-5-styrylisoxazoles, a class of cinnamate synthetic equivalent, with 2-bromomalonate esters under the catalysis of 5 mol% of a Cincona derived phase-transfer catalyst. The reaction allowed multi-gram preparation of desired
Design, synthesis, and biological evaluation of nitroisoxazole-containing spiro[pyrrolidin-oxindole] derivatives as novel glutathione peroxidase 4/mouse double minute 2 dual inhibitors that inhibit breast adenocarcinoma cell proliferation
作者:Shuai-Jiang Liu、Qian Zhao、Cheng Peng、Qing Mao、Fengbo Wu、Feng-Hua Zhang、Quan-Sheng Feng、Gu He、Bo Han
DOI:10.1016/j.ejmech.2021.113359
日期:2021.5
(GPX4)/mouse double minute 2 (MDM2) dual inhibitors. Bioactive spirooxindole and isoxazole skeletons were combined, and the resulting compounds exhibited strong activities against both targets. In particular, compound 3d displayed excellent activity in the suppression of MDM2-mediated degradation of p53, as well as levels of GPX4, in MCF-7 breast cancercells. Moreover, 3d also exhibited inhibitory
Highly diastereoselective assembly of isoxazole and trifluoromethyl containing spiro[pyrrolidin-oxindoles] from N-2,2,2-trifluoroethyl-substituted isatin imines and styrylisoxazoles
The highly diastereoselective 1,3-dipolar cycloaddition reaction of N-2,2,2-trifluoroethyl-substituted isatin imines with styrylisoxazoles was developed for the synthesis of a wide range of isoxazole- and trifluoromethyl-containing spiro[pyrrolidin-oxindoles] in high yields with excellent diastereoselectivities. Further transformations of the final products and the gram-scale capacity of this method
Chiral Squaramide Catalyzed Enantioselective 1,6-Michael Addition of Pyrazolin-5-ones to Styrylisoxazole Derivatives
作者:Vivek Sharma、Jasneet Kaur、Swapandeep S. Chimni
DOI:10.1002/ejoc.201800589
日期:2018.7.13
The cinchonidine squaramide catalyzed enantioselective 1,6‐Michaeladdition reaction of 3‐methyl‐4‐nitro‐5‐alkenylisoxazoles and pyrazolin‐5‐ones has been developed. Under mild reaction conditions, heterocyclic products that contain both pyrazole and isoxazole moieties were produced in up to 91 % yield with enantiomeric ratios (er) up to 91:9.