- Visual detection of formaldehyde by highly selective fluorophore labeling via gold(iii) complex-mediated three-component coupling reaction
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A novel method for visual detection of formaldehyde with excellent selectivity via a gold(iii) complex-mediated three-component coupling reaction of resin-linked sterically bulky amines and fluorescent alkynes has been developed.
- Wong, Kong-Fan,Deng, Jie-Ren,Wei, Xiao-Qun,Shao, Shi-Ping,Xiang, Da-Peng,Wong, Man-Kin
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Read Online
- Hydrazine Hydrate Accelerates Neocuproine–Copper Complex Generation and Utilization in Alkyne Reduction, a Significant Supplement Method for Catalytic Hydrogenation
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Diimine (HN═NH) is a strong reducing agent, but the efficiency of diimine oxidized from hydrazine hydrate or its derivatives is still not good enough. Herein, we report an in situ neocuproine–copper complex formation method. The redox potential of this complex enable it can serve as an ideal redox catalyst in the synthesis of diimine by oxidation of hydrazine hydrate, and we successfully applied this technique in the reduction of alkynes. This reduction method displays a broad functional group tolerance and substrate adaptability as well as the advantages of safety and high efficiency. Especially, nitro, benzyl, boc, and sulfur containing alkynes can be reduced to the corresponding alkanes directly, which provides a useful complementary method to traditional catalytic hydrogenation. Besides, we applied this method in the preparation of the Alzheimer’s disease drug CT-1812 and studied the mechanism.
- Chen, Guoliang,He, Xiaoyan,Huang, Gang,Lu, Xiuhong,Wang, Jincheng,Yang, Zhenjiao,Zhang, Yongsheng,Zhang, Zeng
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p. 17696 - 17709
(2021/12/09)
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- An Electrochemical Beckmann Rearrangement: Traditional Reaction via Modern Radical Mechanism
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Abstract: Electrosynthesis as a potential means of introducing heteroatoms into the carbon framework is rarely studied. Herein, the electrochemical Beckmann rearrangement, i. e. the direct electrolysis of ketoximes to amides, is presented for the first time. Using a constant current as the driving force, the reaction can be easily carried out under neutral conditions at room temperature. Based on a series of mechanistic studies, a novel radical Beckmann rearrangement mechanism is proposed. This electrochemical Beckmann rearrangement does not follow the trans-migration rule of the classical Beckmann rearrangement.
- Tang, Li,Wang, Zhi-Lv,He, Yan-Hong,Guan, Zhi
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p. 4929 - 4936
(2020/08/21)
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- INHIBITORS OF HEPATITIS C VIRUS REPLICATION
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The present invention relates to compounds of formula (I) that are useful as hepatitis C virus (HCV) NS5A inhibitors, the synthesis of such compounds, and the use of such compounds for inhibiting HCV NS5A activity, for treating or preventing HCV infections and for inhibiting HCV viral replication and/or viral production in a cell-based system.
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Paragraph 0795-0796
(2019/05/15)
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- SO2F2-Mediated Oxidative Dehydrogenation and Dehydration of Alcohols to Alkynes
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Direct synthesis of alkynes from inexpensive, abundant alcohols was achieved in high yields (greater than 40 examples, up to 95% yield) through a SO2F2-promoted dehydration and dehydrogenation process. This straightforward transformation of sp3-sp3 (C-C) bonds to sp-sp (C=C) bonds requires only inexpensive and readily available reagents (no transition metals) under mild conditions. The crude alkynes are sufficiently free of impurities to permit direct use in further transformations, as illustrated by regioselective Huisgen alkyne-azide cycloaddition reactions with PhN3 to give 1,4-substituted 1,2,3-traiazoles (16 examples, up to 92% yield) and Sonogashira couplings (10 examples, up to 77% yield).
- Zha, Gao-Feng,Fang, Wan-Yin,Li, You-Gui,Leng, Jing,Chen, Xing,Qin, Hua-Li
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supporting information
p. 17666 - 17673
(2019/01/04)
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- Visible-Light-Mediated Photoredox-Catalyzed Regio- and Stereoselective Chlorosulfonylation of Alkynes
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Herein, a one-step chlorosulfonylation of alkynes via a photocatalytic redox process is described. A variety of commercially available sulfonyl chlorides can be applied for the generation of sulfonyl radical species under visible-light irradiation. Regio- and stereoselective addition of the sulfonyl radical and chloride leads to the efficient formation of (E)-selective β-chlorovinyl sulfones from a broad range of terminal and internal alkynes. The reported method represents an operationally simple and mild way to furnish vinyl sulfones.
- Chakrasali, Prashant,Kim, Kyuneun,Jung, Young-Sik,Kim, Hyejin,Han, Soo Bong
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supporting information
p. 7509 - 7513
(2019/01/03)
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- Multicomponent Oxidative Trifluoromethylation of Alkynes with Photoredox Catalysis: Synthesis of α-Trifluoromethyl Ketones
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The direct oxidative addition of CF3 and H2O to alkynes was achieved with photoredox catalysis to obtain α-trifluoromethyl ketones via rapid enol-keto tautomerization. The reaction exhibits high functional group tolerance and regioselectivity. Heterocycles of various sizes containing CF3 were synthesized from the α-CF3-substituted diketones obtained through the protocol, thereby demonstrating the versatile applicability of the method. Mechanistic studies of the reaction with isotopes provided insight into the reaction pathway.
- Malpani, Yashwardhan R.,Biswas, Bishyajit Kumar,Han, Hong Sik,Jung, Young-Sik,Han, Soo Bong
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supporting information
p. 1693 - 1697
(2018/04/16)
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- INDOLINONE DERIVATIVES AS INHIBITORS OF MATERNAL EMBRYONIC LEUCINE ZIPPER KINASE
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The present disclosure relates to indolinone compounds, compositions, and methods for the inhibition of maternal embryonic leucine zipper kinase (MELK). The present disclosure further relates to indolinone compounds, compositions, and methods for the treatment or prevention of a cancer (for example, triple negative breast cancer).
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Page/Page column 92
(2018/09/20)
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- Based on metal catalyzed coupling reaction of formaldehyde in food detection method and kit therefor (by machine translation)
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The invention provides a method and a kit for detecting formaldehyde in food based on metal catalysis coupling reaction. The metal catalysis coupling reaction comprises that coupling reaction is carried out on formaldehyde, amine and alkyne in presence of
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Paragraph 0076
(2017/08/26)
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- Pyrimidine or pyridine pyridine ketone compound and its preparation method and application (by machine translation)
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The invention discloses a kind of type I of the pyrimidine or pyridine pyridine ketone compound and its preparation and application, which belongs to the technical field of pharmaceutical preparation. The compounds have high-efficient and selectively inhibit the cell cycle dependent kinases (Cdks) CDK4 and CDK6 active, and then by inhibiting CDK4/CDK6 prevent tumor cell division. Therefore, the compounds of this invention can be used for CDK4 and CDK6 the involved in cell cycle control disorders result in various diseases, especially suitable for the treatment of malignant tumors. (by machine translation)
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- Catalyst-free hydrochlorination protocol for terminal arylalkynes with hydrogen chloride
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We present a simple and straightforward protocol for hydrochlorination of terminal arylalkynes to vinyl chlorides using hydrogen chloride under mild reaction conditions. This protocol does not involve any metal catalysts or additives. It is simple, inexpensive, and easy to prepare, and exhibits good reaction activity. The hydrochlorination proceeds smoothly to yield unique regioselective products via the Markovnikov addition rule.
- Xu, Cai-Xia,Ma, Cun-Hua,Xiao, Fu-Rong,Chen, Hong-Wei,Dai, Bin
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p. 1683 - 1685
(2016/11/12)
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- Homogenous suspension of immunopotentiating compounds and uses thereof
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The present invention generally relates to homogeneous suspensions of small molecule immune potentiators (SMIPs) that are capable of stimulating or modulating an immune response in a subject in need thereof. The homogeneous suspensions may be used in combinations with various antigens or adjuvants for vaccine therapies.
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Page/Page column 135
(2016/09/12)
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- Visual detection of formaldehyde by highly selective fluorophore labeling via gold(III) complex-mediated three-component coupling reaction
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A novel method for visual detection of formaldehyde with excellent selectivity via a gold(iii) complex-mediated three-component coupling reaction of resin-linked sterically bulky amines and fluorescent alkynes has been developed.
- Wong, Kong-Fan,Deng, Jie-Ren,Wei, Xiao-Qun,Shao, Shi-Ping,Xiang, Da-Peng,Wong, Man-Kin
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supporting information
p. 7408 - 7411
(2015/11/27)
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- Synthesis and antiviral evaluation of 4′-(1,2,3-triazol-1-yl) thymidines
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Non-obligate chain terminating nucleosides with a linear substituent (azido or ethynyl group) at the 4′ position represent an important class of compounds in antiviral discovery, particularly against hepatitis C virus (HCV) and human immunodeficiency virus (HIV). We have previously shown that 3′-azidothymidine (AZT)-derived 1,2,3-triazoles can be potent inhibitors of HIV-1. To gauge the medicinal chemistry impact of functionalizing the 4′-linear substituent and possibly generate novel antiviral nucleoside scaffolds, we have explored azide-alkyne cycloaddition reactions with 4′-azidothymidine (ADRT). The Ru-mediated reaction failed and the Cu-catalyzed variant generated 1,2,3-triazoles (9a-y) with only modest yields and efficiencies, indicating a substantial steric barrier around the 4′-azido group. Antiviral screening identified a few triazole analogues moderately active against HIV-1 (18-62% inhibition at 10 μM) and/or influenza A virus (15-50% inhibition at 10 μM), and none active against West Nile virus (WNV) or HCV. These results suggest that the linear 4′ azido group of ADRT may be essential for target binding and that its chemical manipulation could largely compromise antiviral potency. This journal is the Partner Organisations 2014.
- Vernekar, Sanjeev Kumar V.,Qiu, Li,Zacharias, Jeana,Geraghty, Robert J.,Wang, Zhengqiang
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supporting information
p. 603 - 608
(2014/05/06)
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- Synthesis, stereocontrol and structural studies of highly luminescent chiral tris-amidepyridyl-triazacyclononane lanthanide complexes
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The configuration of the remote amide chiral moiety determines the helicity of the metal complex in Ln(iii) complexes of nonadentate N6O 3 ligands based on triazacyclononane. Solution NMR studies revealed the presence of a dominant isomer whose proportion varies from 9:1 to 4:1 from Ce to Yb and X-ray crystallographic studies at 120 K of the Yb and two enantiomeric Eu complexes confirmed the configuration as S-Δ-λ in the major isomer. Global minimisation methods allowed magnetic susceptibility and electronic relaxation times of the lanthanide ions to be estimated by analysis of variable field longitudinal relaxation rate (R1) data sets. A set of four europium complexes, containing different para-substituted pyridinyl-aryl groups, exist as one major isomer (15:1), and absorb light strongly via an ICT transition in the range 320 to 355 nm (ε = 55 to 65000 M-1 cm-1). The two examples absorbing light at 332 nm, possess overall emission quantum yields of 35 and 37% in aerated water, making these systems as bright as any Eu complex in solution. This journal is the Partner Organisations 2014.
- Neil, Emily R.,Funk, Alexander M.,Yufit, Dmitry S.,Parker, David
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p. 5490 - 5504
(2014/04/03)
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- NOVEL COMPLEXING AGENTS AND CORRESPONDING LANTHANIDE COMPLEXES
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The present invention concerns complexing agents of formula (I) in which a, b, c, chrom1, chrom2, chrom3, R3, R4 and R5 are as defined in the description. The invention also concerns lantha
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Paragraph 0266
(2014/11/27)
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- Palladium-catalyzed coupling between aryl halides and trimethylsilylacetylene assisted by dimethylaminotrimethyltin
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Palladium-catalyzed coupling between aryl halides, especially less reactive ones or N-heteroaryls, and trimethylsilylacetylene in the presence of dimethylaminotrimethyltin generated the coupled products in high yields. The reaction does not need CuI and base as auxiliary agents.
- Cai, Liangzhen,Yang, Dujuan,Sun, Zhonghua,Tao, Xiaochun,Cai, Lisheng,Pike, Victor W.
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p. 1059 - 1062
(2012/01/04)
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- INHIBITORS OF HEPATITIS C VIRUS REPLICATION
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The present invention relates to compounds of formula (I) that are useful as hepatitis C virus (HCV) NS5A inhibitors, the synthesis of such compounds, and the use of such compounds for inhibiting HCV NS5A activity, for treating or preventing HCV infections and for inhibiting HCV viral replication and/or viral production in a cell-based system.
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Page/Page column 125
(2010/11/04)
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- Oxidative amide synthesis and N-terminal α-amino group ligation of peptides in aqueous medium
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A new method for oxidative synthesis of amides from alkynes and amines in high yields (up to 96%) using [Mn(2,6-Cl2TPP)Cl] 1 as a catalyst and Oxone/H2O2 as an oxidant in aqueous medium has been developed. This method could be used for N-terminal α-amino group ligation of unprotected peptides with aryl, aliphatic, and internal alkynes under mild conditions. Copyright
- Chan, Wing-Kei,Ho, Chi-Ming,Wong, Man-Kin,Che, Chi-Ming
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p. 14796 - 14797
(2008/02/05)
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- Substituted 5-alkynyl pyrimidines having neurotrophic activity
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The present invention relates to a series of novel substituted 5-alkynyl pyrimidines, pharmaceutical compositions which contain them, methods for their preparation, and their use in therapy, particularly in the treatment of neurodegenerative or other neurological disorders of the central and peripheral nervous systems, including age related cognitive disorders such as senility and Alzheimer's disease, nerve injuries, peripheral neuropathies, and seizure disorders such as epilepsy.
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- Arylsulfonamidobenzylic compounds
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Arylsulfonamidobenzyl alcohols, amines and sulfonamides are provided which are useful in treating lipid disorders, metabolic diseases and cell-proliferative diseases.
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- Aryl acetylenes as mechanism-based inhibitors of cytochrome P450- dependent monooxygenase enzymes
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Aryl acetylenes have been investigated as inhibitors of cytochrome P450 (P450)-dependent alkoxyresorufin dealkylation activities in liver microsomes prepared from rats exposed to β-naphthoflavone, isosafrole, or phenobarbital. Many of the acetylenes investigated produce pseudo-first- order time-dependent and NADPH-dependent losses of the dealkylation activities characteristic of mechanism-based irreversible inactivation (suicide inhibition). Replacing the terminal hydrogen of aryl acetylenes with a methyl group to convert ethynes into propynes enhances the inhibition of P450 1A enzymes; in some instances, this modification converts a reversible inhibitor of P450s into a suicide inhibitor. In contrast, ethynes are more effective suicide inhibitors of P450 2B-dependent dealkylations than the corresponding propynes. Aryl acetylenes with an ethynyl group on the 2 position of naphthalene or on the 9 position of phenanthrene and arylalkyl acetylenes with alkyl chains containing 2, 3, or 4 methylene groups are selective inhibitors of P450 2B1/2B2 in liver microsomes from rats. Aryl acetylenes also act as suicide inhibitors of P450 1A2 in human liver microsomes, of purified P450 1A2 from rabbit or rat liver in reconstituted systems, and of purified recombinant human P450 1A2 and 1A1 in reconstituted systems. 4-(1-Propynyl)biphenyl (4PBi) inactivated P450 1A2-dependent ethoxyresourfin deethylation (EROD) activity in human liver microsomes in an NADPH-dependent process (k(inactivation), 0.23 min-1; K1, 2.3 μM). 4PBi also inactivated purified recombinant human P450 1A2 (k(inactivation), 0.24 min-1; K(I), 4.3 μM). In agreement with previous reports [Yun, C.-H., Hammons, G. J., Jones, G., Martin, M. V., Hopkins, N. E., Alworth, W. L., and Guengerich, F. P. (1992) Biochemistry 31, 10556-10563], 2-ethyny]naphthalene (2EN) was not a suicide inhibitor of the P450 1A2 activity in human liver microsomes but did inactivate purified human P450 1A2. Neither 4PBi nor 2EN affected diagnostic activities of human microsomal P450 2E1, 2C9/10, 3A4, or 2C19. In the systems examined, the losses of P450-dependent activity produced by these aryl acetylenes were not accompanied by corresponding decreases in the measured P450 absorption spectra. Thus P450 inactivation by these aryl acetylenes does not involve labeling and destruction of the heme. Incubation of 4PBi with microsomal P450 1A1 or 1A2 from rat liver under conditions that lead to P450-dependent enzyme inactivations generates a 2-biphenylylpropionic acid product. This suggests that the suicide inhibition of P450s by propynylaryl acetylenes proceeds via a methylaryl ketene formed by a 1,2- methyl rearrangement, analogous to the mechanism of suicide inhibition by ethynyl acetylenes that proceed via ketene intermediates formed by 1,2- hydrogen shifts [Ortiz de Montellano, P. R., and Kunze, K. L. (1981) Arch. Biochem. Biophys. 209, 710-712].
- Foroozesh, Maryam,Primrose, Ginny,Guo, Zuyu,Bell, L. Chastine,Alworth, William L.,Guengerich, F. Peter
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