- Triptycenyl Sulfide: A Practical and Active Catalyst for Electrophilic Aromatic Halogenation Using N-Halosuccinimides
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A Lewis base catalyst Trip-SMe (Trip = triptycenyl) for electrophilic aromatic halogenation using N-halosuccinimides (NXS) is introduced. In the presence of an appropriate activator (as a noncoordinating-anion source), a series of unactivated aromatic compounds were halogenated at ambient temperature using NXS. This catalytic system was applicable to transformations that are currently unachievable except for the use of Br2 or Cl2: e.g., multihalogenation of naphthalene, regioselective bromination of BINOL, etc. Controlled experiments revealed that the triptycenyl substituent exerts a crucial role for the catalytic activity, and kinetic experiments implied the occurrence of a sulfonium salt [Trip-S(Me)Br][SbF6] as an active species. Compared to simple dialkyl sulfides, Trip-SMe exhibited a significant charge-separated ion pair character within the halonium complex whose structural information was obtained by the single-crystal X-ray analysis. A preliminary computational study disclosed that the πsystem of the triptycenyl functionality is a key motif to consolidate the enhancement of electrophilicity.
- Nishii, Yuji,Ikeda, Mitsuhiro,Hayashi, Yoshihiro,Kawauchi, Susumu,Miura, Masahiro
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supporting information
p. 1621 - 1629
(2020/02/04)
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- Design, synthesis, and preliminary biological evaluation of 3′,4′,5′-trimethoxy flavonoid salicylate derivatives as potential anti-tumor agents
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According to the pharmacophore combination principle, a set of new 3′,4′,5′-trimethoxy flavonoid salicylate derivatives were designed, synthesized, and evaluated for biological activity. The cytotoxicity evaluation revealed that compound 10v exhibited higher potency than 5-Fu against HCT-116 cells. Preliminary biological activity studies showed that compound 10v could inhibit the colony formation and migration of HCT-116 cells. Besides, the Hoechst 33258 staining assay and flow cytometry revealed that treatment with compound 10v induced the apoptosis of HCT-116 cells in a concentration-dependent manner, while it had no effect on their cell cycle. The WB analysis suggested that HIF-1α, tubulin, HK-2, and PFK might be the potential pharmacophore targets of compound 10v. Tubulin was a potential drug target for compound 10v, which was explained by analyzing the crystal structure of compound 10v complexed with tubulin. These results indicated that compound 10v might be a promising anti-tumor agent candidate, deserving further optimization and evaluation.
- Deng, Xiangping,Liu, Renbo,Li, Junjian,Li, Zhongli,Liu, Juan,Xiong, Runde,Lei, Xiaoyong,Zheng, Xing,Xie, Zhizhong,Tang, Guotao
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p. 1874 - 1884
(2019/01/28)
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- Room temperature C(sp2)-H oxidative chlorination: Via photoredox catalysis
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Photoredox catalysis has been developed to achieve oxidative C-H chlorination of aromatic compounds using NaCl as the chlorine source and Na2S2O8 as the oxidant. The reactions occur at room temperature and exhibit exclusive selectivity for C(sp2)-H bonds over C(sp3)-H bonds. The method has been used for the chlorination of a diverse set of substrates, including the expedited synthesis of key intermediates to bioactive compounds and a drug.
- Zhang, Lei,Hu, Xile
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p. 7009 - 7013
(2017/10/05)
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- Copper-catalyzed formal c-h carboxylation of aromatic compounds with carbon dioxide through arylaluminum intermediates
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The C-H bond carboxylation of various aromatic compounds with CO2 was achieved by the deprotonative alumination with a mixed alkyl amido lithium aluminate compound iBu3Al(TMP)Li followed by the NHC-copper-catalyzed carboxylation of the resulting arylaluminum species, which afforded the corresponding carboxylation products in high yield and high selectivity. In addition to benzene derivatives, heteroarenes such as benzofuran, benzothiophene, and indole derivatives are also suitable substrates. Functional groups such as Cl, Br, I, vinyl, amide, and CN could survive the reaction conditions. Some key reaction intermediates such as the copper aryl and isobutyl complexes and their carboxylation products were isolated and structurally characterized by X-ray crystallographic analyses, thus offering important information on the reaction mechanism.
- Ueno, Atsushi,Takimoto, Masanori,Wylie,Nishiura, Masayoshi,Ikariya, Takao,Hou, Zhaomin
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supporting information
p. 1010 - 1016
(2015/03/31)
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- Anion binding of N-(o-Methoxybenzamido)thioureas: Contribution of the intramolecular hydrogen bond in the N-benzamide moiety
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N-(o-Methoxybenzamido)- thioureas (2X/2Y) are found to show an enhanced anion binding affinity with binding constants over 107 mol -1L orders of magnitude for AcO- and a redshifted absorption of the anion binding complexes in acetonitrile (MeCN) relative to those of N-benzamidothioureas (1) that bear no o- OMe in the N-benzamide moiety, despite the electron-donating character of o-OMe. Absorption of the anion-2X/ 2Y complex was shown to be of the same charge-transfer nature as that of the anion-1 complex, but its dependence on substituent X is interestingly influenced by the o-MeO···HNC=O six-membered-ring intramolecular hydrogen bond identified in 2X/2Y. Such an intramolecular hydrogen bond is suggested to be responsible for the enhanced anion binding affinity. In the presence of this intramolecular hydrogen bond, the anion binding constant of 2X was found to be independent of substituent X at the N-phenyl ring, as in the case of 1, whereas that of 2Y showed an amplified dependence on substituent Y at the N′-phenyl ring, but to a lower extent than that of 1. A similar ring intramolecular hydrogen bond was purported to exist in 2Za, 2Zd, and 2Ze, which bear NHMe, F, and Cl as the ortho substituent in the N-benzamide moiety. In terms of the current roles of thiourea in not only anion recognition and sensing but also organocatalysis and crystal engineering, the present finding would be of significance for a wider structural diversity of smart thiourea derivatives with predesigned functions.
- Jiang, Qian-Qian,Darhkijav, Burenkhangai,Liu, Hao,Wang, Fang,Li, Zhao,Jiang, Yun-Bao
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experimental part
p. 543 - 549
(2010/08/20)
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- In vitro affinities of various halogenated benzamide derivatives as potential radioligands for non-invasive quantification of D2-like dopamine receptors
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Benzamide derivatives as radiotracers have played an important role in diagnosing malfunction in dopaminergic neurotransmission. A variety of halogenated and two unsubstituted benzamide derivatives were synthesised and their in vitro affinities to dopaminergic, serotonergic and adrenergic receptors and their lipophilicities were determined. As references IBZM (3), raclopride (4) and FLB457 (5) were tested as well. The two iodinated compounds NAE (27) and NADE (28) displayed Ki values of 0.68 and 14 nM for the D2 receptor. The well-established radiotracers FP (1) and DMFP (2) showed affinities in the same range as did the brominated compounds NABrE (29) and NABrDE (30). The log D7.4 values of 2.91 for NAE (27) and of 2.81 for NADE (28) are in the range of those found for IBZM (3), FP (1) and DMFP (2). These facts allow to expect good properties for the two iodinated compounds NAE (27) and NADE (28) regarding in vivo imaging with SPECT.
- Stark, Daniela,Piel, Markus,Huebner, Harald,Gmeiner, Peter,Gruender, Gerhard,Roesch, Frank
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p. 6819 - 6829
(2008/03/27)
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- NOVEL AMIDE COMPOUNDS
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A compound of the formula (I):R1-A-X-NHCO-Y-R2 ???whereinR1 is heterocyclic group which may have suitable substituents, or phenyl which may have suitable substituents,R2 is condensed phenyl which may have suitable substituents, phenyl which may have suitable substituents, or thienyl which may have suitable substituents,A is a group of the formula:-(CH2)t-(O)m- or in which R3 and R4 are each hydrogen or linked together to form imino,R5 is hydrogen or lower alkyl,t is 0, 1 or 2,p, m and n are each 0 or 1,X is phenylene which may have suitable substituents, or bivalent heterocyclic group containing nitrogen which may have suitable substituents,Y is bond, lower alkylene, or lower alkenylene, and a salt thereof.
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- Novel substituted 3H-1,2,3,5-oxathiadiazole 2-oxides useful as anthihyperglycemic agents
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This invention relates to novel substituted 3H-1,2,3,5-oxathiadiazole 2-oxides, to the processes for their preparation, to methods for using the compounds, and to pharmaceutical compositions thereof. The compounds have pharmaceutical properties which render them beneficial for the treatment of diabetes mellitus and associated conditions.
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- Benzofuro[3,2-c]pyrazol-3-amine derivatives
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Herein is disclosed benzofuro[3,2-c]pyrazol-3-amine derivatives, therapeutically acceptable acid addition salts thereof, processes for their preparation, methods of using the derivatives and pharmaceutical compositions. The derivatives are useful for producing analgesia in a mammal. In addition, some of the derivatives are useful for inhibiting gastric acid secretion, convulsions, anxiety and aggression, and producing muscle relaxation, hypnosis and sedation in a mammal.
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- Process for preparing p-(5-chloro-2-methoxy-benzamidoethyl)-benzene sulfonamide
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A process for preparing p-[5-chloro-2-methoxy-benzamidoethyl]-benzene sulfonamide consisting of treating 5-chlorosalicylic acid or its ester by methylating and aminolysis to form N-phenethyl-5-chloro-2-methoxybenzamide followed by chlorosulfonation and aminolysis.
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