Rh<sub>2</sub>(II)-Catalyzed Nitro-Group Migration Reactions: Selective Synthesis of 3-Nitroindoles from β-Nitro Styryl Azides
作者:Benjamin J. Stokes、Sheng Liu、Tom G. Driver
DOI:10.1021/ja111060q
日期:2011.4.6
Rhodium carboxylate complexes (1 mol %) catalyze the migration of electron-withdrawing groups to selectively produce 3-substituted indoles from beta-substituted styryl azides. The relative order of migratorial aptitude for this transformation is ester << amide < H < sulfonyl < benzoyl << nitro.
Stereodivergent Synthesis of Tetrahydrofuroindoles through Pd-Catalyzed Asymmetric Dearomative Formal [3+2] Cycloaddition
作者:Qiang Cheng、Fang Zhang、Yue Cai、Yin-Long Guo、Shu-Li You
DOI:10.1002/anie.201711873
日期:2018.2.19
palladium‐catalyzed asymmetric dearomative formal [3+2] cycloaddition of nitroindoles with epoxybutenes was developed. The polarity of the solvent was found to play a key role in the diastereoselectivity. In toluene, good to excellent yields (70–99 %), diastereoselectivity (87/13‐>95/5 d.r.), and enantioselectivity (85/15–94/6 e.r.) were obtained, regardless of the properties of the substituents on
Indole derivatives 3-amino-6-carboxyl-indole and 3-nitro-6-amino-indole were designed and synthesized based on the TolC structure. They proved to have potent synergistic antibacterial effects on chloramphenicol, tetracycline, erythromycin, and ciprofloxacin against Escherichia coli YD2 and FJ307 with decreased minimal inhibitory concentrations (MICs) at 2–64 folds. To research its functional site, Escherichia coli BL21(DE3)−3 expressing a target-site mutated TolC was constructed by red homologous recombination and the site-directed mutagenesis technique. They did not noticeably affect antimicrobial activity against BL21(DE3)−3. All the results indicate that these compounds match our design and can be developed as efflux pump inhibitors for the AcrAB-TolC efflux pump.