Rearrangement of Dypnones to 1,3,5-Triarylbenzenes
摘要:
Rearrangement of dypnones to 1,3,5-triarylbenzenes is described. The reaction is proposed to involve an aldol-type self-condensation of dypnones, followed by an intramolecular [2 + 2] cycloaddition and a retro-[2 + 2] cycloaddition. The reaction goes smoothly under obviously milder conditions in comparison to the cyclotrimerization of acetophenones to 1,3,5-triarylbenzenes (10 mol % of TsOH, 80 degrees C versus 130-148 degrees C). This unexpected rearrangement would provide new possible considerations in dypnone-involved organic synthesis.
合成并评价了新型3,3-螺萘烷化的5-芳基,6-芳基乙烯基取代的1,2,4-三恶烷19-34通过口服途径对瑞士小鼠多药耐药性约氏疟原虫的抗疟活性从96 mg / kg x 4天到24 mg / kg x 4天。该系列中活性最高的化合物(化合物25)在24 mg / kg x 4天时提供了100%的保护,其他1,2,4-三恶烷22、26、27和30也显示出良好的活性。在该模型中,β-蒿甲醚通过口服途径分别以48 mg / kg x 4天和24 mg / kg x 4天提供100%和20%的保护。化合物25的体外药代动力学特征与参考药物β-蒿醚的相似。活性结果证明在1,2,4-三恶烷药效团的C-5位上的芳基部分很重要。
Deoxygenativechlorination of carbonyl compounds using the HMe2SiCl/FeCl3/EtOAc and HMeSiCl2/FeCl3/EtOAc systems has been systemically investigated. The HMe2SiCl-FeCl3 system showed the advantages of good substrate applicability, mild reaction conditions, simple operation, low cost, and easy availability of raw materials. Also, it provided a simple and efficient synthesis route for carbonyl deoxychlorination
Access to Cyclic β‐Amino Acids by Amine‐Catalyzed Enantioselective Addition of the γ‐Carbon Atoms of α,β‐Unsaturated Imines to Enals
作者:Guoyong Luo、Zhijian Huang、Shitian Zhuo、Chengli Mou、Jian Wu、Zhichao Jin、Yonggui Robin Chi
DOI:10.1002/anie.201908896
日期:2019.11.25
approach for an efficient access to cyclic β-amino acids widely found in bioactive small molecules and peptidic foldamers. Our method involves addition of the remote γ-carbon atoms of α,β-unsaturated imines to enals by iminium organic catalysis. This highly chemo- and stereo-selective reaction affords cyclic β-amino aldehydes that can be converted to amino acids bearing quaternary stereocenters with
β-Substituted α,β-unsaturated carbonyl compounds were obtained in moderate to high yields by a 1,4-addition of organocuprates to enol phosphate intermediates formed in situ from triethyl phosphite and 2-bromo-1,3-dicarbonyl compounds.
Abstract Air-stable zirconocene bis(perfluoroctanesulfonate)s [Cp2Zr]OSO2C8F17)2] (1) with high Lewis acidity and high thermal stability was prepared by the reaction between Cp2ZrCl2 and AgOSO2C8F17. The as-prepared complex 1 exhibits good activity and selectivity in the cyclotrimerization of various ketones to the desired 1,3,5-triaylbenzenes. Furthermore, in the cyclic experiments, the complex 1
Pd-catalyzed imine-directed intramolecular C N bond formation through C(sp3) H activation: An efficient approach to multisubstituted pyrroles
作者:Ting Yu、Qiang Zhu、Shuang Luo
DOI:10.1016/j.tetlet.2020.151887
日期:2020.5
An atom-economic approach to synthesize 1,2,4-trisubstituted pyrroles through palladium-catalyzed imine-directed intramolecularC(sp3)H amination reaction has been developed. The imine group acts as a directing group as well as an intramolecular nucleophile for the first time in intramolecular CN bonds formation reactions.