- Synthesis of Vicinal Quaternary All-Carbon Centers via Acid-catalyzed Cycloisomerization of Neopentylic Epoxides
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We report our studies on the development of a catalytic cycloisomerization of 2,2-disubstituted neopentylic epoxides to produce highly substituted tetralins and chromanes. Termination of the sequence occurs via Friedel-Crafts-type alkylation of the remote (hetero)arene linker. The transformation is efficiently promoted by sulfuric acid and proceeds best in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as the solvent. Variation of the substitution pattern provided detailed insights into the migration tendencies and revealed a competing disproportionation pathway of dihydronaphthalenes.
- Schmid, Matthias,Sokol, Kevin R.,Wein, Lukas A.,Torres Venegas, Sofia,Meisenbichler, Christina,Wurst, Klaus,Podewitz, Maren,Magauer, Thomas
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supporting information
p. 6526 - 6531
(2020/09/02)
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- CO2-Catalyzed oxidation of benzylic and allylic alcohols with DMSO
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CO2-catalyzed transition-metal-free oxidation of alcohols has been achieved. Earlier, several methodologies have been explored for alcohol oxidations based on transition-metal catalysts. However, owing to the cheaper price, easy separation and nontoxicity, transition-metal-free systems are in high demand to the pharmaceutical industries. For this reason, various primary and secondary alcohols have been selectively oxidized to the corresponding carbonyl compounds using CO2 as a catalyst in the presence of different functional groups such as nitrile, nitro, aldehyde, ester, halogen, ether, and so on. At the end, transition-metal-free syntheses of pharmaceuticals have also been achieved. Finally, the role of CO2 has been investigated in detail, and the mechanism is proposed on the basis of experiments and DFT calculations.
- Riemer, Daniel,Mandaviya, Bhavdip,Schilling, Waldemar,G?tz, Anne Charlotte,Kühl, Torben,Finger, Markus,Das, Shoubhik
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p. 3030 - 3034
(2018/04/14)
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- Synthesis and antitumor evaluation of 5-(benzo[: D] [1,3]dioxol-5-ylmethyl)-4-(tert -butyl)- N -arylthiazol-2-amines
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A series of novel N-aryl-5-(benzo[d][1,3]dioxol-5-ylmethyl)-4-(tert-butyl)thiazol-2-amines (C1-C31) were synthesized and evaluated for their antitumor activities against HeLa, A549 and MCF-7 cell lines. Some tested compounds showed potent growth inhibition properties with IC50 values generally below 5 μM against the three human cancer cells lines. Compound C27 showed potent activities against HeLa and A549 cell lines with IC50 values of 2.07 ± 0.88 μM and 3.52 ± 0.49 μM, respectively. Compound C7 (IC50 = 2.06 ± 0.09 μM) was the most active compound against A549 cell line, while compound C16 (IC50 = 2.55 ± 0.34 μM) showed the best inhibitory activity against the MCF-7 cell line. The preliminary mechanism of the inhibitory effect was investigated via further experiments, such as morphological analysis by dual AO/EB staining and Hoechst 33342 staining, and cell apoptosis and cycle assessment by FACS analysis. The results illustrated that compound C27 could induce apoptosis and cause both S-phase and G2/M-phase arrests in HeLa cell line. Therefore, compound C27 could be developed as a potential antitumor agent.
- Wu,Fang,Tang,Xiao,Ye,Li,Hu
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p. 1768 - 1774
(2016/09/28)
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- 5 - piperonyl - 4 - alkyl - 2 - aryl amino thiazole and its preparation method and application
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The invention relates to 5-piperonyl-4-alkyl-2- aromatic aminothiazole shown in the chemical structural formula I (seen in the specification) or salt thereof. R in the formula I is selected from a C1-C2 alkyl group or a C3-C4 linear chain alkyl group or a branched-chain alkyl group. X is selected from CH or N. X1 is selected from hydrogen or deuterium or C1-C2 alkyl group or fluorine or chlorine or bromine. X2 and X4 are selected from hydrogen or deuterium or C1-C2 alkyl group or fluorine or chlorine or bromine or a trichloromethyl or a tribromomethyl or a trifluoromethyl. X3 is selected from hydrogen or deuterium or C1-C2 alkyl group or fluorine or chlorine or bromine or a trichloromethyl or a tribromomethyl or a trifluoromethyl. The salt is selected from hydrochloride or hydrobromide or sulfate or phosphate or nitrate. The 5-piperonyl-4-alkyl-2- aromatic aminothiazole or the salt thereof is used for preparing bacteriacide or pesticides.
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Paragraph 0024; 0026
(2017/02/24)
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- 5 - piperonyl - 4 - alkyl - 2 - animal pen Asia amino thiazole and its preparation method and application
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The invention relates to 5-piperonyl-4-alkyl-2-benzyliminothiazole shown in the chemical structural formula I (seen in the specification). R is selected from a C1-C2 alkyl group or a C3-C4 linear chain alkyl group or a branched-chain alkyl group. X1 and X5 are selected from hydrogen or deuterium or C1-C2 alkyl group or a hydroxyl or a methoxy group or an oxyethyl group or fluorine or chlorine or bromine. X2 and X4 are selected from hydrogen or deuterium or C1-C2 alkyl group or fluorine or chlorine or bromine or iodine or a nitryl. X3 is selected from hydrogen or deuterium or C1-C2 alkyl group or fluorine or chlorine or bromine or nitryl. The 5-piperonyl-4-alkyl-2-benzyliminothiazole is used for preparing bacteriacide or pesticides or herbicides.
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Paragraph 0026
(2017/02/24)
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- One-pot synthesis of multifunctionalized cyclopropanes
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A facile one-step synthetic protocol toward multifunctionalized cyclopropanes 4 is developed from substituted chalcones 1 and sulfones 2 in good yields via a [2C+1C] annulation.
- Chang, Meng-Yang,Chen, Yi-Chia,Chan, Chieh-Kai
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p. 2257 - 2263
(2014/03/21)
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