- Novel Meta-iodobenzylguanidine-Based Copper Thiosemicarbazide-1-guanidinomethylbenzyl Anticancer Compounds Targeting Norepinephrine Transporter in Neuroblastoma
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Meta-iodobenzylguanidine (MIBG) is a ligand with high affinity against norepinephrine transporter (NET) that has been used for diagnostic imaging and radionuclide therapy of NET-expressing tumors, such as neuroblastoma. We hypothesize that MIBG can be used as a ligand for development of new anticancer drugs targeting NET-expressing neuroblastoma (NB). To test our hypothesis, we synthesized two MIBG-based anticancer copper complexes [Cu(m-TSBG)2 and Cu(p-TSBG)2] by conjugation of a thiosemicarbazone copper group onto MIBG ligand. Both Cu(m-TSBG)2 and Cu(p-TSBG)2 compounds showed potent anticancer activity against NB cells (BE2C and SK-N-DZ cells). The NB-specific anticancer activity of Cu(m-TSBG)2 and Cu(p-TSBG)2 was further demonstrated by the reduced anticancer activities when nonconjugated MIBG ligand was used to competitively block binding of Cu(m-TSBG)2 or Cu(p-TSBG)2 onto NET-expressing NB cells. Both Cu(m-TSBG)2 or Cu(p-TSBG)2 compounds hold potential as promising new drugs for targeted therapy of neuroblastoma and other NET-expressing tumors.
- Zhang, Haiyuan,Xie, Fang,Cheng, Muhua,Peng, Fangyu
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- IBX oxidation of benzenedimethanols in the presence of cucurbit[8]uril
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The cucurbit[8]uril (Q[8]) mediated oxidation of benzenedimethanols with o-iodoxybenzoic acid (IBX) in aqueous solution has been investigated, and the results reveal the supramolecular catalysis depends on the electronic and geometric structure of substrate. In the cases of o-benzenedimethanol (1a) and m-benzenedimethanol (1b), the IBX oxidation could be obviously enhanced by the addition of Q[8] at different extent. There is no observation of the catalytic activity of Q[8] when p-benzenedimethanol (1c) is subjected to the IBX oxidation. The addition amount of Q[8] is discussed herein, and the addition of more than 10% mol catalyst cannot improve the oxidation much more. The investigation of host-guest interactions by isothermal titration calorimetry implies the supramolecular catalysis is related to the formation of complexes between benzenedimethanols and cucurbit[8]uril. The supramolecular catalysis of Q[8] (cucurbit[8]uril) on the IBX (o-iodoxybenzoic acid) oxidation of o,m,p-benzenedimethanols in aqueous solvent and the host-guest interactions have been investigated.
- Cong, Hang,Chen, Qiuju,Geng, Qingxia,Tao, Zhu,Yamato, Takehiko
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- Biomass-derived phosphorus-doped carbon materials as efficient metal-free catalysts for selective aerobic oxidation of alcohols
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Heteroatom-doped carbon materials (HDCMs) with abundant active functional groups and stable structural characteristics are promising catalysts for eco-friendly metal-free catalysis. In this work, phosphorus-doped carbon materials with a highly porous structure and extremely high surface area (>1600 m2 g-1) were successfully prepared via a convenient and scalable strategy using easily available soluble starch and phosphoric acid, which are expected to show good performance in mass-transfer and thus promote the catalytic process. As expected, the as-prepared PC-700 catalyst showed remarkable catalytic performance in aerobic oxidation of benzyl alcohol with a higher TOF value than other previously reported heteroatom-doped carbon catalysts. It also exhibited great tolerance for various substrates, including aromatic, alicyclic, heterocyclic, and aliphatic alcohols. On the basis of the related characterization studies and experimental results, it was proved that the P-O-C species and the defects caused by P-O species doping in the PC-700 catalyst are the active sites for aerobic oxidation. A unique mechanism was proposed for the catalytic process, which is different from that of N-doped graphene and graphene oxide catalyzed reactions that follow a free radical mechanism. In addition, the recycling test and characterization of the reused catalyst indicate that the PC-700 shows extraordinary performance in terms of both recyclability and stability and retains high reactivity even after eight cycles.
- Hu, Xiwei,Fan, Mengying,Zhu, Yangyang,Zhu, Qian,Song, Qiang,Dong, Zhengping
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- Synthesis and characterization of complexes imparting N-pyridyl bonded meso-pyridyl substituted dipyrromethanes
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The meso-pyridyl substituted dipyrromethane ligands 5-(4-pyridyl)dipyrromethane (4-dpmane) and 5-(3-pyridyl)dipyrromethane (3-dpmane) have been employed in the synthesis of a series of complexes with the general formulations [(η6-arene)RuCl2(L)] (η6-arene = C6H6, C10H14) and [(η5-C5Me5)MCl2(L)] (M = Rh, Ir). The reaction products have been characterized by microanalyses and spectral studies and molecular structures of the complexes [(η6-C10H14)RuCl2(4-dpmane)] and [(η5-C5Me5)IrCl2(3-dpmane)] have been determined crystallographically. For comparative studies, geometrical optimization have been performed on the complex [(η5-C5Me5)IrCl2(4-dpmane)] using exchange correlation functional B3LYP. Optimized bond length and angles are in good agreement with the structural data of the complex [(η5-C5Me5)IrCl2(3-dpmane)]. The complexes [(η6-C10H14)RuCl2(3-dpmane)], [(η5-C5Me5)RhCl2(3-dpmane)] and [(η5-C5Me5)IrCl2(3-dpmane)] have been employed as a transfer hydrogenation catalyst in the reduction of aldehydes. It was observed that the rhodium and iridium complexes mentioned above are more effective in this regard in comparison to the ruthenium complex.
- Yadav, Mahendra,Singh, Ashish Kumar,Pandey, Rampal,Pandey, Daya Shankar
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- Synthesis of Oxasmaragdyrin–Amino Acid Conjugates
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A series of covalently linked oxasmaragdyrin-amino acid and BF2-oxasamaragdyrin–amino acid conjugates were synthesized by treating oxasmaragdyrin or its BF2 complex that contain a benzylhydroxyl group at one of the meso positions with an appropriate fluorenylmethyloxycarbonyl-protected amino acid in CH2Cl2 in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide·HCl/hydroxybenzotriazole under basic conditions at room temperature. The conjugates are stable, highly soluble in all organic solvents, and confirmed by HRMS. 1D and 2D NMR spectroscopic techniques were used to characterize the oxasmaragdyrin–amino acid conjugates. Absorption, fluorescence, and electrochemical studies of conjugates indicate that the conjugates strongly absorb and emit in visible-NIR region with decent quantum yields, singlet state lifetimes and are stable under electrochemical conditions. Furthermore, the conjugates showed minimal change in their spectral and electrochemical properties relative to that of the unconjugated oxasmaragdyrin or its BF2 complex suggest that the characteristic features of the oxasmaragdyrin and its BF2 complex is retained in the conjugates, which will be a useful feature for Near-IR fluorescence imaging and other applications.
- Laxman, Kandala,Ravikanth, Mangalampalli
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- One-pot synthesis and PEGylation of hyperbranched polyacetals with a degree of branching of 100%
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The Bronsted acid-catalyzed polytransacetalization of hydroxymethylbenzaldehyde dimethylacetal (1), a commercially available AB 2-type monomer, led to hyperbranched polyacetals (HBPA's) with a degree of branching (DB) around 0.5 by forming methanol as byproduct. In sharp contrast, the polyacetalization of the nonprotected homologue, namely, hydroxymethylbenzaldehyde (2), yielded HBPA's with DB = 1, by forming water as byproduct, under the same acidic conditions. This major difference arises from the instability of the initially formed hemiacetal intermediates, which react faster than aldehyde moieties, driving the polyacetalization toward the quantitative formation of dendritic acetal units. This represents a rare example of defect-free hyperbranched polymer synthesis utilizing a very simple AB 2-type monomer. Bronsted acid catalysts included p-toluenesulfonic, camphorsulfonic, and pyridinium camphorsulfonic acids. Trapping of the water generated during polyacetalization of 2 was accomplished using molecular sieves regularly renewed, which allowed achieving polymers of relatively high molar masses. These HBPA's with DB = 1 featuring multiple aldehyde functions at their periphery were further derivatized into PEGylated HBPA's, using linear amino-terminated poly(ethylene oxide)s of different molar masses. This led to submicrometric sized HBPA's with a core-shell architecture. Finally, HBPA derivatives could be readily hydrolyzed under acidic conditions (e.g., pH = 4), owing to the acid sensitivity of their constitutive acetal linkages.
- Liu, Na,Vignolle, Joan,Vincent, Jean-Marc,Robert, Frederic,Landais, Yannick,Cramail, Henri,Taton, Daniel
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- Application of bioorthogonal hetero-Diels-Alder cycloaddition of 5-arylidene derivatives of 1,3-dimethylbarbituric acid and vinyl thioether for imaging inside living cells
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New bioorthogonal cycloaddition of 5-arylidene derivatives of 1,3-dimethylbarbituric acid as 1-oxa-1,3-butadienes and vinyl thioether as a dienophile has been applied to imaging inside living cells. The reaction is high yielding, selective, and fast in aqueous media. The proposed 1-oxa-1,3-butadiene derivative conjugated to a FITC fluorochrome selectively and rapidly labels the cancer cells pretreated with the dienophile-taxol. The second order rate constants k2 for various proposed bioorthogonal cycloadditions were estimated to be in the range from 0.9 × 10-2 M-1 s-1 to 1.4 M-1 s-1, which is much better than in the case of the first generation TQ-ligation (o-quinolinone quinone methide and vinyl thioether ligation, k2 = 1.5 × 10-3 M-1 s-1) and comparable or better to that for the second generation TQ-ligation (k2 = 2.8 × 10-2 M-1 s-1). The reaction rate constants k2 of proposed ligation reactions are in the range of the rate constants k2 for tetrazines and norbornenes or tetrazines and cyclopropenes. These findings indicate that this chemistry is suitable for in vitro imaging experiments.
- Bazan, Bart?omiej,Pa?asz, Aleksandra,Skalniak, ?ukasz,Cie?, Dariusz,Buda, Szymon,J?drzejowska, Katarzyna,G?omb, Sonia,Kamzol, Daniel,Czarnota, Kinga,Latos, Krystian,Kozie?, Krzysztof,Musielak, Bogdan
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supporting information
p. 6045 - 6058
(2021/07/25)
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- Efficient and chemoselective hydrogenation of aldehydes catalyzed by well-defined PN3-pincer manganese(ii) catalyst precursors: An application in furfural conversion
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Well-defined and air-stable PN3-pincer manganese(ii) complexes were synthesized and used for the hydrogenation of aldehydes into alcohols under mild conditions using MeOH as a solvent. This protocol is applicable for a wide range of aldehydes containing various functional groups. Importantly, α,β-unsaturated aldehydes, including ynals, are hydrogenated with the CC double bond/CC triple bond intact. Our methodology was demonstrated for the conversion of biomass derived feedstocks such as furfural and 5-formylfurfural to furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol respectively.
- Gholap, Sandeep Suryabhan,Dakhil, Abdullah Al,Chakraborty, Priyanka,Li, Huaifeng,Dutta, Indranil,Das, Pradip K.,Huang, Kuo-Wei
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supporting information
p. 11815 - 11818
(2021/11/30)
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- Histone deacetylase inhibitor as well as preparation and application thereof
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The invention relates to a histone deacetylase inhibitor and preparation and an application thereof, in particular to a novel histone deacetylase inhibitor based on a beta-elemene structure and a preparation method thereof, and further relates to an intermediate for synthesizing the histone deacetylase inhibitor and a preparation method thereof. The invention also relates to an application of the histone deacetylase inhibitor in preparation of antitumor drugs, and belongs to the technical field of chemical synthesis of drugs. The zinc ion combined compound and the salt or solvate thereof are shown as a general formula (I) or (II), wherein R, X, n and i are described in the claims and the specification.
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Paragraph 0042-0043
(2021/04/28)
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- Synthesis and evaluation of novel α-aminoamides containing benzoheterocyclic moiety for the treatment of pain
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Novel α-aminoamide derivatives containing different benzoheterocyclics moiety were synthesized and evaluated as voltage-gated sodium ion channels blocks the treatment of pain. Compounds 6a, 6e, and 6f containing the benzofuran group displayed more potent in vivo analgesic activity than ralfinamide in both the formalin test and the writhing assay. Interestingly, they also exhibited potent in vitro anti-Nav 1.7 and anti-Nav 1.8 activity in the patch-clamp electrophysiology assay. Therefore, compounds 6a, 6e, and 6f, which have inhibitory potency for two pain-related Nav targets, could serve as new leads for the development of analgesic medicines.
- Cheng, Jingchao,He, Junlin,Ren, Fengxia,Ren, Fengzhi,Shi, Weiguo,Tong, Kun,Yu, Zixing,Zhang, Ruotian,Zhang, Tao,Zhang, Yatong
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- A mild and selective Cu(II) salts-catalyzed reduction of nitro, azo, azoxy, N-aryl hydroxylamine, nitroso, acid halide, ester, and azide compounds using hydrogen surrogacy of sodium borohydride
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The first mild, in situ, single-pot, high-yielding well-screened copper (II) salt-based catalyst system utilizing the hydrogen surrogacy of sodium borohydride for selective hydrogenation of a broad range of nitro substrates into the corresponding amine under habitancy of water or methanol like green solvents have been described. Moreover, this catalytic system can also activate various functional groups for hydride reduction within prompted time, with low catalyst-loading, without any requirement of high pressure or molecular hydrogen supply. Notably, this system explores a great potential to substitute expensive traditional hydrogenation methodologies and thus offers a greener and simple hydrogenative strategy in the field of organic synthesis.
- Kalola, Anirudhdha G.,Prasad, Pratibha,Mokariya, Jaydeep A.,Patel, Manish P.
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supporting information
p. 3565 - 3589
(2021/10/12)
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- The Stereoselective Oxidation of para-Substituted Benzenes by a Cytochrome P450 Biocatalyst
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The serine 244 to aspartate (S244D) variant of the cytochrome P450 enzyme CYP199A4 was used to expand its substrate range beyond benzoic acids. Substrates, in which the carboxylate group of the benzoic acid moiety is replaced were oxidised with high activity by the S244D mutant (product formation rates >60 nmol.(nmol-CYP)?1.min?1) and with total turnover numbers of up to 20,000. Ethyl α-hydroxylation was more rapid than methyl oxidation, styrene epoxidation and S-oxidation. The S244D mutant catalysed the ethyl hydroxylation, epoxidation and sulfoxidation reactions with an excess of one stereoisomer (in some instances up to >98 %). The crystal structure of 4-methoxybenzoic acid-bound CYP199A4 S244D showed that the active site architecture and the substrate orientation were similar to that of the WT enzyme. Overall, this work demonstrates that CYP199A4 can catalyse the stereoselective hydroxylation, epoxidation or sulfoxidation of substituted benzene substrates under mild conditions resulting in more sustainable transformations using this heme monooxygenase enzyme.
- Chao, Rebecca R.,Lau, Ian C.-K.,Coleman, Tom,Churchman, Luke R.,Child, Stella A.,Lee, Joel H. Z.,Bruning, John B.,De Voss, James J.,Bell, Stephen G.
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supporting information
p. 14765 - 14777
(2021/09/14)
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- Biocatalytic Cross-Coupling of Aryl Halides with a Genetically Engineered Photosensitizer Artificial Dehalogenase
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Devising artificial photoenzymes for abiological bond-forming reactions is of high synthetic value but also a tremendous challenge. Disclosed herein is the first photobiocatalytic cross-coupling of aryl halides enabled by a designer artificial dehalogenase, which features a genetically encoded benzophenone chromophore and site-specifically modified synthetic NiII(bpy) cofactor with tunable proximity to streamline the dual catalysis. Transient absorption studies suggest the likelihood of energy transfer activation in the elementary organometallic event. This design strategy is viable to significantly expand the catalytic repertoire of artificial photoenzymes for useful organic transformations.
- Fu, Yu,Huang, Jian,Wu, Yuzhou,Liu, Xiaohong,Zhong, Fangrui,Wang, Jiangyun
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supporting information
p. 617 - 622
(2021/02/03)
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- Integration of Earth-Abundant Photosensitizers and Catalysts in Metal-Organic Frameworks Enhances Photocatalytic Aerobic Oxidation
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We report here the construction of two metal-organic frameworks (MOFs), Zr6-Cu/Fe-1 and Zr6-Cu/Fe-2, by integrating earth-abundant cuprous photosensitizers (Cu-PSs) and Fe catalysts for photocatalytic aerobic oxidation. Site isolation and pore confinement stabilize both Cu-PSs and Fe catalysts, while the proximity between active centers facilitates electron and mass transfer. Upon visible light irradiation and using O2 as the only oxidant, Zr6-Cu/Fe-1 and Zr6-Cu/Fe-2 efficiently oxidize alcohols and benzylic compounds to afford corresponding carbonyl products with broad substrate scopes, high turnover numbers of up to 500 with a 9.4-fold enhancement over homogeneous analogues, and excellent recyclability in four consecutive runs. Control experiments, spectroscopic evidence, and computational studies revealed the photo-oxidation mechanism: Oxidative quenching of [Cu-PS]? by O2 affords [CuII-PS], which efficiently oxidizes FeIII-OH to generate a hydroxyl radical for substrate oxidation. This work highlights the potential of MOFs in promoting earth-abundant metal-based photocatalysis.
- Feng, Xuanyu,Pi, Yunhong,Song, Yang,Xu, Ziwan,Li, Zhong,Lin, Wenbin
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p. 1024 - 1032
(2021/01/26)
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- Boosting multiple photo-assisted and temperature controlled reactions with a single redox-switchable catalyst: Solvents as internal substrates and reducing agent
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An alternative and economically viable process for the synthesis of β-aryl enals, enones and the aryl amines has been developed by partial oxidation of ethanol, isopropanol and N, N-dimethyl formamide (DMF). The formation of β-aryl enals, enones and the aryl amines was catalyzed by a mixed metal oxides layer of cobalt and chromium supported on halloysite nanotubes, designated as CoCr2O4-HNT. The C[sbnd]C and C[sbnd]N bond formation reactions were found to be influenced by temperature and the nature of base. The condensation of aldehyde with in situ generated acetaldehyde by ethanol oxidation forming β-aryl enals occurred selectively at 120 °C. The partial oxidation of isopropanol to acetone and its condensation with aldehydes forming β-aryl enones occurred at room temperature. Increase in temperature caused the liberation of hydrogen gas from isopropanol and allowed the reversible reduction of aldehydes to alcohols. Increase in temperature in isopropanol and increase in base concentration in ethanol causes the selective reduction of aldehydes to alcohols. Besides being active for the Claisen-Schmidt type of reactions and the aryl halides amination process, the synthesized catalyst was also found to be highly active for the photocatalytic oxidation of benzyl alcohols in absence of any external oxidizing agent. The positive holes (h+) generated at the Co(II) site as evident from EPR analysis was considered to be responsible for high photocatalytic activity of the material reducing the recombination rate of holes and electrons (e?). Density Functional Theory calculations were performed to understand the mechanism of ethanol oxidation to acetaldehyde.
- Bania, Kusum K.,Baruah, Manash J.,Bhattacharyya, Pradip K.,Das, Biraj,Karunakar, Galla V.,Roy, Subhasish,Saikia, Lakshi,Saikia, Pinku,Sharma, Mukesh
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p. 104 - 121
(2020/06/01)
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- Self-reporting heavy atom-free photodynamic therapy agents
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Two novel, self-reporting distyryl BODIPY-based photodynamic therapy agents functionalized with singlet oxygen responsive imidazole and tertiary amine moieties are developed. Heavy atom-free photosensitizers are demonstrated to have efficient photodynamic action in MCF7 cells. The fluorescence intensity of the photosensitizers is shown to be reduced as a result of 1O2 generation without any significant change in photodynamic activity. This journal is
- Demirok, Naime,Erbas-Cakmak, Sundus,Kayadibi Koygun, Gozde,Turkoglu, Gulsen,Yurt, Mediha Nur Zafer
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supporting information
p. 9433 - 9437
(2020/12/15)
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- Amide derivative containing benzoheterocycle structure, and composition and application thereof
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The invention belongs to the technical field of medicines, and discloses an amide derivative containing a benzoheterocycle structure, and a composition and an application thereof. The amide derivativecontaining the benzoheterocycle structure is a compound represented by structural formula I and a nontoxic pharmaceutically acceptable salt thereof, or the amide derivative containing the benzoheterocycle structure is a compound represented by structural formula II or a nontoxic pharmaceutically acceptable salt thereof. The amide derivative containing the benzoheterocycle structure has good analgesic activity and good inhibition effect on a target sodium ion channel Nav1.7.
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Paragraph 0140-0144
(2020/06/17)
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- Site-Selective Alkoxylation of Benzylic C?H Bonds by Photoredox Catalysis
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Methods that enable the direct C?H alkoxylation of complex organic molecules are significantly underdeveloped, particularly in comparison to analogous strategies for C?N and C?C bond formation. In particular, almost all methods for the incorporation of alcohols by C?H oxidation require the use of the alcohol component as a solvent or co-solvent. This condition limits the practical scope of these reactions to simple, inexpensive alcohols. Reported here is a photocatalytic protocol for the functionalization of benzylic C?H bonds with a wide range of oxygen nucleophiles. This strategy merges the photoredox activation of arenes with copper(II)-mediated oxidation of the resulting benzylic radicals, which enables the introduction of benzylic C?O bonds with high site selectivity, chemoselectivity, and functional-group tolerance using only two equivalents of the alcohol coupling partner. This method enables the late-stage introduction of complex alkoxy groups into bioactive molecules, providing a practical new tool with potential applications in synthesis and medicinal chemistry.
- Lee, Byung Joo,DeGlopper, Kimberly S.,Yoon, Tehshik P.
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supporting information
p. 197 - 202
(2019/11/26)
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- CEPHEM COMPOUNDS WITH LATENT REACTIVE GROUPS AND METHODS OF USING AND MAKING SAME
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The present application provides novel cephem, penem, and monobactam compounds that exhibit antibiotic activity against both Gram-negative and Gram-positive bacteria, as well as compositions comprising these compounds and methods of using these compounds and compositions to treat bacterial infections.
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Paragraph 0378; 0386-0387
(2020/10/19)
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- Design, synthesis and study of antibacterial and antitubercular activity of quinoline hydrazone hybrids
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Emerging bacterial resistance is causing widespread problems for the treatment of various infections. Therefore, the search for antimicrobials is a never-ending task. Hydrazones and quinolines possess a wide variety of biological activities. Herewith, eleven quinoline hydrazone derivatives have been designed, synthesized, characterized and evaluated for their antibacterial activity and antitubercular potential against Mtb WT H37Rv. Compounds QH-02, QH-04 and QH-05 were found to be promising compounds with an MIC value of 4 μg/mL against Mtb WT H37Rv. Compounds QH-02, QH-04, QH-05, and QH-11 were also found to be active against bacterial strains including Acinetobacter baumanii, Escherichia coli and Staphylococcus aureus. Further, we have carried out experiments to confirm the cytotoxicity of the active compounds and found them to be non-toxic.
- Eswaran, Sumesh,Shruthi, T. G.,Subramanian, Sangeetha
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p. 137 - 147
(2020/11/12)
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- Ancillary ligands switch the activity of Ru–NHC-based oxidation precatalysts
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Herein we demonstrate how the inner-sphere coordinating ligands switch the activity of Ru–NHC-based oxidation precatalysts in the oxidative conversion of olefins to carbonyl compounds, with the help of a series of systematically varied imidazolydene-NHC (Im-NHC) and triazolydene-NHC (Tz-NHC)-based ruthenium(II)-complexes. It is shown that the catalytic activity of the para-cymene-containing precatalysts varies in the order of [(Tz-NHC)Ru(para-cymene)Cl]+ > [(Im-NHC)Ru(para-cymene)Cl]+, while the order of activity of the MeCN-containing precatalysts is found to be reversed, i.e., [(Im-NHC)Ru(MeCN)4]2+ > [(Tz-NHC)Ru(MeCN)4]2+. Along with the electronic influence of the NHC ligands, the effect of the lability of the para-cymene and MeCN ligands, and the overall charge of the complexes might be attributed toward such a switching of catalytic activity. This finding led to develop a new precatalyst with improved activity which was further utilized in selective oxidation of a series of styrene substrates containing other oxidation-sensitive functionalities.
- Gupta, Suraj K.,Mandal, Tanmoy,Gangber, Tejaswinee,Singh, Vivek,Choudhury, Joyanta
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supporting information
(2019/10/28)
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- Reversing Chemoselectivity: Simultaneous Positive and Negative Catalysis by Chemically Equivalent Rims of a Cucurbit[7]uril Host
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Enzyme catalysis has always been an inspiration and an unattainable goal for chemists due to features such as high specificity, selectivity, and efficiency. Here, we disclose a feature neither common in enzymes nor ever described for enzyme mimics, but one that could prove crucial for the catalytic performance of the latter, namely the ability to catalyze and inhibit two different reactions at the same time. Remarkably, this can be realized by two identical, spatially resolved catalytic sites. In the future, such a synchronized catalyst action could be used not only for controlling chemoselectivity, as in the present case, but also for regulating other types of chemical reactivity.
- Rad, Nazar,Danylyuk, Oksana,Sashuk, Volodymyr
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p. 11340 - 11343
(2019/07/16)
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- Chemoselective reduction of aldehydes: Via a combination of NaBH4 and acetylacetone
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A bench-stable combination of NaBH4-acetylacetone was developed for the efficient chemoselective reduction of aldehydes in the presence of ketones. This method offers a useful synthetic protocol for distinguishing carbonyl reaction sites, and its synthetic utility is reflected by its moisture tolerance and high efficiency in a variety of complex settings.
- Sui, Guoqing,Lv, Qingyun,Song, Xiaoqing,Guo, Huihui,Dai, Jiatong,Ren, Li,Lee, Chi-Sing,Zhou, Wenming,Hao, Hong-Dong
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supporting information
p. 15793 - 15796
(2019/10/19)
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- Enhanced Solution and Solid-State Emission and Tunable White-Light Emission Harvested by Supramolecular Approaches
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Organic luminescent materials with high quantum yields and/or white-light-emitting properties in particular play a crucial role in labeling and optoelectronic devices. In this work we have synthesized a new 2,3,6,7-tetramethoxy-9,10-di-p-tolylanthracene-bridged pillar[5]arene dimer with persistent mazarine blue fluorescent emission and much higher quantum yields in both solution and the solid state in comparison with its corresponding emissive linker without pillarene units, which exhibits typical aggregation-caused quenching. According to the fluorescence data and single-crystal analyses, their contrasting fluorescent performances can be rationally ascribed to their different stacking structures and intermolecular interactions. Three fluorescent guests containing different chromophores and/or terminal binding sites have also been synthesized to interact with the pillar[5]arene dimer to construct supramolecular ensembles with highly controllable luminescence, taking advantage of the stimuli-responsive properties of the supramolecular host–guest interactions. Intriguingly, multicolor fluorescence, including white-light emission (0.31, 0.35), which is in high demand, has been achieved by tuning the molar ratio of the host and guest and/or by changing the solvent system. This strategy holds great potential for the design and development of fluorescent materials with high quantum yields, controllable emission wavelength, and good stimuli-responsiveness.
- Lou, Xin-Yue,Song, Nan,Yang, Ying-Wei
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p. 11975 - 11982
(2019/08/26)
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- PH clock instructed transient supramolecular peptide amphiphile and its vesicular assembly
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A new strategy to construct a transient supramolecular peptide amphiphile (SPA) and its vesicular aggregates is displayed. The construction of the amphiphile is assisted by the ternary complexation of cucurbit[8]uril and pH responsive imine bond formation. The transient assembly follows a pH clock set by urea/urease and hydrolysis of glucono delta-lactone (GdL). The transient assembly can be repeated for several cycles through feeding the system with the fuel (urea).
- Dowari, Payel,Das, Saurav,Pramanik, Bapan,Das, Debapratim
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supporting information
p. 14119 - 14122
(2019/12/02)
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- Chemoselective Nucleophilic Functionalizations of Aromatic Aldehydes and Acetals via Pyridinium Salt Intermediates
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The development of a novel chemoselective functionalization can diversify the strategy for synthesizing the target molecules. The perfect chemoselectivity between aromatic and aliphatic aldehydes is difficult to achieve by the previous methods. The aromatic aldehyde-selective nucleophilic addition in the presence of aliphatic aldehydes was newly accomplished. Namely, the aromatic aldehyde-selective nucleophilic addition using arenes and allyl silanes proceeded in the presence of trialkylsilyl triflate and 2,2′-bipyridyl, while the aliphatic aldehydes completely remained unchanged. The reactive pyridinium-type salt intermediate derived from an aromatic aldehyde chemoselectively underwent the nucleophilic substitution. Moreover, the aromatic acetals as the protected aldehydes could be directly transformed into similar pyridinium salt intermediates, which reacted with various nucleophiles coexisting with the aliphatic aldehydes.
- Kawajiri, Takahiro,Kato, Maho,Nakata, Hiroki,Goto, Ryota,Aibara, Shin-Yo,Ohta, Reiya,Fujioka, Hiromichi,Sajiki, Hironao,Sawama, Yoshinari
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p. 3853 - 3870
(2019/03/07)
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- One-Pot Conversion of Allylic Alcohols to α-Methyl Ketones via Iron-Catalyzed Isomerization-Methylation
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A one-pot iron-catalyzed conversion of allylic alcohols to α-methyl ketones has been developed. This isomerization-methylation strategy utilized a (cyclopentadienone)iron(0) carbonyl complex as precatalyst and methanol as the C1 source. A diverse range of allylic alcohols undergoes isomerization-methylation to form α-methyl ketones in good isolated yields (up to 84% isolated yield).
- Latham, Daniel E.,Polidano, Kurt,Williams, Jonathan M. J.,Morrill, Louis C.
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supporting information
p. 7914 - 7918
(2019/10/16)
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- Co-conformational mechanoisomerism in a calix[6]arene-based [2]rotaxane
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The synthesis of a [2]rotaxane, comprising a calix[6]arene-wheel and a dibenzyl-ammonium axle, is here reported. By virtue of its inherent directionality, the calix-wheel makes non-degenerate two equivalent stations of the symmetrical axle. In this way, the neutral rotaxane shows two co-conformations, named endo-alkyl and endo-benzyl, in which an alkyl or benzyl moiety of the axle are included inside the calix-cavity, respectively. NMR and DFT studies showed that the co-conformation preferred by the neutral mechanomolecule is the ‘endo-alkyl’ one, which is more stabilized by C-H···π interactions between the included alkyl chain and the aromatic wall of the calix-cavity.
- Talotta, Carmen,De Rosa, Margherita,Soriente, Annunziata,Spinella, Aldo,Gaeta, Carmine,Neri, Placido
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- A novel porphyrin derivative, composition for detecting cyanide ion comprising the same and method for detecting cyanide ion using the same
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The present invention provides a novel dicyanovinyl porphyrin compound, a composition for detecting cyanide ion containing the same, and a method for detecting cyanide ion using the same. The dicyanovinyl porphyrin compound, the composition for detecting cyanide ion containing the same and the method for detecting cyanide ion using the same of the present invention can be usefully used as a cyanide ion specific detection technique in a field of cyanide ion detection.COPYRIGHT KIPO 2019
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Paragraph 0072-0073; 0083-0084; 0089
(2019/05/01)
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- The effect of pore size and layer number of metal-porphyrin coordination nanosheets on sensing DNA
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Metal-organic framework (MOF) nanosheets are a new type of two-dimensional nanomaterial. Their properties and performances are expected to correlate strongly with the sheet structure, particularly the number of layers (sheet thickness). Yet, synthetically controlling the layer number at the molecular scale is highly difficult. Herein, a facile method is introduced to fabricate substrate-supported MOF nanosheets with precisely controllable layer numbers, using the Langmuir-Blodgett technique. Large-area, porous, and uniform MOF nanosheets, based on 5,10,15,20-tetrakis[4′-(terpyridinyl)phenyl]porphyrin-cobalt(ii) (Co-TTPP) coordination polymer, were constructed and characterized in detail by atomic force microscopy, transmission electron microscopy, energy dispersive spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and a photoelectronic conversion technique. As a prototype sensor device, a series of substrate-supported Co-TTPP nanosheets was further investigated for the fluorescence detection of DNA towards rapid clinical diagnosis. The ten-layer Co-TTPP nanosheet exhibits an impressive performance with a very low detection limit of ca. 0.1 nM, outstanding specificity, and multiplexed DNA detection, comparable to some top-notch free-standing nanomaterial sensors. Importantly, our results also revealed the synergistic contributions of suitable pore size and optimal layer number of the Co-TTPP nanosheet for highly efficient DNA detection for the first time.
- Liu, Chenxi,Wang, Tianyu,Ji, Jing,Wang, Chiming,Wang, Hailong,Jin, Peng,Zhou, Wei,Jiang, Jianzhuang
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supporting information
p. 10240 - 10246
(2019/08/28)
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- Selective oxidation of exogenous substrates by a bis-Cu(III) bis-oxide complex: Mechanism and scope
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Cu(III)2(μ-O)2 bis-oxides (O) form spontaneously by direct oxygenation of nitrogen-chelated Cu(I) species and constitute a diverse class of versatile 2e?/2H+ oxidants, but while these species have attracted attention as biomimetic models for dinuclear Cu enzymes, reactivity is typically limited to intramolecular ligand oxidation, and systems exhibiting synthetically useful reactivity with exogenous substrates are limited. OTMPD (TMPD = N1, N1, N3, N3-tetramethylpropane-1,3-diamine) presents an exception, readily oxidizing a diverse array of exogenous substrates, including primary alcohols and amines selectively over their secondary counterparts in good yields. Mechanistic and DFT analyses suggest substrate oxidation proceeds through initial axial coordination, followed by rate-limiting rotation to position the substrate in the Cu(III) equatorial plane, whereupon rapid deprotonation and oxidation by net hydride transfer occurs. Together, the results suggest the selectivity and broad substrate scope unique to OTMPD are best attributed to the combination of ligand flexibility, limited steric demands, and ligand oxidative stability. In keeping with the absence of rate-limiting C–H scission, OTMPD exhibits a marked insensitivity to the strength of the substrate Cα–H bond, readily oxidizing benzyl alcohol and 1-octanol at near identical rates.
- Large, Tao A.G.,Mahadevan, Viswanath,Keown, William,Stack, T. Daniel P.
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p. 782 - 792
(2019/01/03)
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- Storing redox equivalent in the phenalenyl backbone towards catalytic multi-electron reduction
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Storing and transferring electrons for multi-electron reduction processes are considered to be the key steps in various important chemical and biological transformations. In this work, we accomplished multi-electron reduction of a carboxylic acid via a hydrosilylation pathway where a redox-active phenalenyl backbone in Co(PLY-O,O)2(THF)2, stores electrons and plays a preponderant role in the entire process. This reduction proceeds by single electron transfer (SET) from the mono-reduced ligand backbone leading to the cleavage of the Si-H bond. Several important intermediates along the catalytic reduction reaction have been isolated and well characterized to prove that the redox equivalent is stored in the form of a C-H bond in the PLY backbone via a ligand dearomatization process. The ligand's extensive participation in storing a hydride equivalent has been conclusively elucidated via a deuterium labelling experiment. This is a rare example where the ligand orchestrates the multielectron reduction process leaving only the metal to maintain the conformational requirements and fine tunes the electronics of the catalyst.
- Bhunia, Mrinal,Sahoo, Sumeet Ranjan,Shaw, Bikash Kumar,Vaidya, Shefali,Pariyar, Anand,Vijaykumar, Gonela,Adhikari, Debashis,Mandal, Swadhin K.
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p. 7433 - 7441
(2019/08/15)
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- Syntheses of o-iodobenzyl alcohols?BODIPY structures as potential precursors of bimodal tags for positron emission tomography and optical imaging
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Aiming the faster development from bench to bedside of new potential tracers, multimodal tracers for positron emission tomography (PET) and optical imaging (OI) have emerged as a very promising tool. Indeed, they combine the simplicity of use of optical techniques for in vitro/in vivo pre-clinical studies with the various clinical possibilities offered by PET imaging using their radioactive versions. In this context, the preparation of new tags detectable by fluorescence imaging and potentially suitable for PET imaging after a last-step 11C-labeling of the corresponding precursor has been investigated. Various designs and syntheses were explored by linking o-iodobenzyl alcohols and tetramethyl-BODIPY moieties together. Among them, the most promising structure was produced in 30% yield over five steps from a commercially available and inexpensive starting material.
- Christine, Thifanie,Tabey, Alexis,Cornilleau, Thomas,Fouquet, Eric,Hermange, Philippe
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- VOLTAGE SENSITIVE DYES
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Voltage sensitive dyes comprising boron and related compositions and methods are provided. In some embodiments, a voltage sensitive dye comprises an electron acceptor comprising boron. The electron acceptor may be attached (e.g., covalently) to at least one electron donating group and at least one polar group. For instance, the electron acceptor may comprise optionally substituted boron dipyrromethene (e.g., optionally substituted 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene). The point of attachment and chemical nature of the electron donating group(s) and polar group(s) may be selected to impart beneficial properties to the voltage sensitive dye. For instance, the voltage sensitive dye may have an extended difference in the dipole moment between the ground and electronic states due at least in part to the position of the electron donating group(s). The voltage sensitive dyes, described herein, may have high specificity, high signal to noise ratio, fast responsivity, high voltage sensitivity, high photostability, and/or high brightness.
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Page/Page column 52; 53
(2018/12/13)
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- Supported Rhodium Nanoparticles Catalyzed Reduction of Nitroarenes, Arylcarbonyls and Aryl/Benzyl Sulfoxides using Ethanol/Methanol as In Situ Hydrogen Source
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A facile reduction reaction of nitroarenes, aryl carbonyls and aryl/benzyl sulfoxides was performed under polystyrene supported rhodium (Rh@PS) catalyzed conditions using ethanol/methanol as in situ hydrogen source. The catalyst Rh@PS played a pivotal role in the oxidation of ethanol/methanol in the presence of traces of aerial oxygen and base to produce hydrogen gas, enough for further reduction reaction. Transmission electron microscopy (TEM) analysis indicated that the average particle size of the Rh nanoparticles (NPs) lies between 2–3 nm; this is responsible for its high catalytic activity. The advantages of Rh@PS are its catalytic activity, easy preparation, recovery, recyclability for several runs, and low metal leaching during reaction. (Figure presented.).
- Sharma, Saurabh,Bhattacherjee, Dhananjay,Das, Pralay
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supporting information
p. 2131 - 2137
(2018/04/17)
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- Preparation, characterization and heterogeneous catalytic applications of GO/Fe3O4/HPW nanocomposite in chemoselective and green oxidation of alcohols with aqueous H2O2
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Graphene oxide-Fe3O4-NH3 +H2PW12O40 - magnetic nanocomposite (GO/Fe3O4/HPW) was prepared by linking amino-functionalized Fe3O4 nanoparticles (Fe3O4-NH2) on the graphene oxide (GO), and then grafting 12-tungstophosphoric acid (H3PW12O40) on the graphene oxide-magnetite hybrid (GO-Fe3O4-NH2). The obtained GO/Fe3O4/HPW nanocomposite was well characterized with different techniques such as FT-IR, TEM, SEM, XRD, EDX, TGA-DTA, AGFM, ICP and BET measurements. The used techniques showed that the graphene oxide layers were well prepared and the various stages of preparation of the GO/Fe3O4/HPW nanocomposites successfully completed. This new nanocomposite displayed excellent performance as a heterogeneous catalyst in the oxidation of alcohols with H2O2. The as-prepared GO/Fe3O4/HPW catalyst was more stable and recyclable at least five times without significantly reducing its catalytic activity.
- Darvishi, Kamran,Amani, Kamal,Rezaei, Manuchehr
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- Indole group-containing alpha-amino amide derivatives and pharmaceutical application thereof
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The invention relates to new indole group-containing alpha-amino amide derivatives represented by the structural formula I or pharmaceutically acceptable salts thereof, pharmaceutical compositions containing the compounds as active ingredients, and an application of the derivatives or the pharmaceutically acceptable salts thereof in preparation of analgesic drugs. In the structural formula I, R is a hydrogen atom or C1-C5 straight-chain alkyl or branched-chain alkyl, and the configuration of carbon atoms connected to R is an R type or an S type.
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Paragraph 0048; 0049
(2018/01/13)
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- Novel alpha-amino amide derivatives and pharmaceutical use thereof
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The invention relates to novel alpha-amino amide derivatives and a pharmaceutical use thereof. Specifically, the invention relates to the alpha-amino amide derivatives represented by the structural formula I or pharmaceutically acceptable salts thereof, pharmaceutical compositions containing the compounds as active ingredients, and the use of the derivatives or the pharmaceutically acceptable salts thereof for preparation of analgesic drugs.
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Paragraph 0045; 0046
(2018/01/13)
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- Carbene-Catalyzed Reductive Coupling of Nitrobenzyl Bromide and Nitroalkene via the Single-Electron-Transfer (SET) Process and Formal 1,4-Addition
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A carbene-catalyzed reductive 1,4-addition of nitrobenzyl bromides to nitroalkenes is disclosed. The reaction proceeds via a carbene-enabled single-electron-transfer process that generates radicals as key intermediates. The present study expands the potentials of carbene catalysis and offers unusual transformations for common substrates in organic synthesis.
- Wang, Yuhuang,Du, Yu,Huang, Xuan,Wu, Xingxing,Zhang, Yuexia,Yang, Song,Chi, Yonggui Robin
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supporting information
p. 632 - 635
(2017/02/10)
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- Direct Carboxylation of the Diazo Group ipso-C(sp2)-H bond with Carbon Dioxide: Access to Unsymmetrical Diazomalonates and Derivatives
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The direct carboxylation of the ipso-C(sp2)-H bond of a diazo compound with carbon dioxide under mild reaction conditions is described. This method is transition-metal-free, uses a weak base, and proceeds at ambient temperature under atmospheric pressure in carbon dioxide. The carboxylation exhibits high reactivity and is amenable to subsequent diversification. A series of unsymmetrical 1,3-diester/keto/amide diazo compounds are obtained with moderate to excellent yields (up to 99%) with good functional group compatibility.
- Liu, Qianyi,Li, Man,Xiong, Rui,Mo, Fanyang
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supporting information
p. 6756 - 6759
(2017/12/26)
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- Roles of phenol groups and auxiliary ligand of copper(II) complexes with tetradentate ligands in the aerobic oxidation of benzyl alcohol
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Herein, six copper(ii) complexes with multidentate ligands, [Cu(HL1)(OAc)(HOAc)] (1), [Cu(HL2)(OAc)] (2), [Cu(HL3)(OAc)] (3), [CuL4(OAc)] (4), [Cu(HL2)Cl] (5), and [Cu(HL3)Cl] (6) {H2L1 = [bis(3-tert-butyl-2-hydroxybenzyl)](2-pyridylmethyl)amine, H2L2 = [(3-tert-butyl-2-hydoxybenzyl)(3-trifluoromethyl-2-hydroxybenzyl) (2-pyridylmethyl)]amine, H2L3 = [bis(3-trifluoromethyl-2-hydroxybenzyl)] (2-pyridylmethyl)amine, and HL4 = [bis(2-pyridylmethyl)] (3-tert-butyl-2-hydroxybenzyl)amine}, are reported. The complexes were characterized by UV-vis spectroscopy, high-resolution mass spectrometry, X-ray single-crystal diffraction analysis and electrochemistry. These copper(ii) complexes have been investigated as catalysts for the aerobic oxidation of benzyl alcohol to benzaldehyde mediated by TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxyl) radical in water at ambient temperature. Mechanistic investigations have revealed that the phenolate/phenol is involved in the intramolecular proton transfer with a bound substrate in catalysis. Hence, the presence of the trifluoromethyl group on the phenol ring significantly affects the catalysis process since the substituent affects the acidity of phenol, and subsequently, the intramolecular proton transfer from the bound substrate. During catalysis, the dissociation of the auxiliary ligand (Cl- or OAc-) occurred in the SN1 pathway, and it is necessary for the substrate to bind. To complete the catalytic cycle, the cleaved auxiliary ligand rebinds to the metal center to regenerate the catalyst.
- Zhan, Guangli,Zhong, Wei,Wei, Zhenhong,Liu, Zhenzhen,Liu, Xiaoming
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p. 8286 - 8297
(2017/07/10)
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- Simple formylation of aromatic compounds using a sodium formate/triphenylphosphine ditriflate system
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A new procedure was developed for formylation of arenes to produce aromatic aldehydes using a sodium formate/triphenylphosphine ditriflate system in ethanol at room temperature in good yields. The simplicity of the procedure, short reaction times, and mild reaction conditions are the other advantages of this metal- and carbon monoxide-free protocol.
- Khodaei, Mohammad M.,Alizadeh, Abdolhamid,Hezarkhani, Hadis Afshar
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supporting information
p. 840 - 843
(2017/06/13)
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- Formamides as Lewis Base Catalysts in SNReactions—Efficient Transformation of Alcohols into Chlorides, Amines, and Ethers
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A simple formamide catalyst facilitates the efficient transformation of alcohols into alkyl chlorides with benzoyl chloride as the sole reagent. These nucleophilic substitutions proceed through iminium-activated alcohols as intermediates. The novel method, which can be even performed under solvent-free conditions, is distinguished by an excellent functional group tolerance, scalability (>100 g) and waste-balance (E-factor down to 2). Chiral substrates are converted with excellent levels of stereochemical inversion (99 %→≥95 % ee). In a practical one-pot procedure, the primary formed chlorides can be further transformed into amines, azides, ethers, sulfides, and nitriles. The value of the method was demonstrated in straightforward syntheses of the drugs rac-Clopidogrel and S-Fendiline.
- Huy, Peter H.,Motsch, Sebastian,Kappler, Sarah M.
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p. 10145 - 10149
(2016/08/16)
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- BENZO[H]QUINOLINE LIGANDS AND COMPLEXES THEREOF
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The present invention provides substituted tridentate benzo[h]quinoline ligands and complexes thereof. The invention also provides the preparation of the ligands and the respective complexes, as well as to processes for using the complexes in catalytic reactions.
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Page/Page column 85-87
(2016/12/22)
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- Chemoselective Transfer Hydrogenation of Aldehydes with HCOONH4 Catalyzed by RuCl(CNNPh)(PP) Pincer Complexes
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Aldehydes were chemoselectively reduced to primary alcohols by using HCOONH4 as the hydrogen donor through transfer hydrogenation catalyzed by benzo[h]quinoline pincer complexes RuCl(CNNPh)(PP) at substrate to catalyst molar ratios of 2000 to 20 000. This practical reaction performed with aldehydes of commercial-grade purity in a water/toluene biphasic system afforded alcohols without the formation of condensation or amination side products.
- Baldino, Salvatore,Facchetti, Sarah,Nedden, Hans Günter,Zanotti-Gerosa, Antonio,Baratta, Walter
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p. 3195 - 3198
(2016/10/24)
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- Synthesis and evaluation of novel α-aminoamides containing an indole moiety for the treatment of neuropathic pain
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The α-aminoamide family of sodium ion channel blockers have exhibited analgesic effects on neuropathic pain. Here, a series of novel α-aminoamides containing an indole ring were designed and synthesized. These compounds were evaluated in mice using a formalin test and they exhibited significant anti-allodynia activities. However, the analgesic mechanism of these compounds remains unclear; a subset of the synthesized compounds can only moderately inhibit the sodium ion channel, Nav1.7, in a whole-cell patch clamp assay. Overall, these results suggest that introduction of an indole moiety to α-aminoamide derivatives can significantly improve their bioactivity and further study is warranted.
- Li, Haotian,Fan, Shiyong,Cheng, Jingchao,Zhang, Ping,Zhong, Bohua,Shi, Weiguo
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- A Bifunctional Photosensitizer for Enhanced Fractional Photodynamic Therapy: Singlet Oxygen Generation in the Presence and Absence of Light
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The photosensitized generation of singlet oxygen within tumor tissues during photodynamic therapy (PDT) is self-limiting, as the already low oxygen concentrations within tumors is further diminished during the process. In certain applications, to minimize photoinduced hypoxia the light is introduced intermittently (fractional PDT) to allow time for the replenishment of cellular oxygen. This condition extends the time required for effective therapy. Herein, we demonstrated that a photosensitizer with an additional 2-pyridone module for trapping singlet oxygen would be useful in fractional PDT. Thus, in the light cycle, the endoperoxide of 2-pyridone is generated along with singlet oxygen. In the dark cycle, the endoperoxide undergoes thermal cycloreversion to produce singlet oxygen, regenerating the 2-pyridone module. As a result, the photodynamic process can continue in the dark as well as in the light cycles. Cell-culture studies validated this working principle in vitro.
- Turan, Ilke Simsek,Yildiz, Deniz,Turksoy, Abdurrahman,Gunaydin, Gurcan,Akkaya, Engin U.
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supporting information
p. 2875 - 2878
(2016/02/27)
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- A traceless photocleavable linker for the automated glycan assembly of carbohydrates with free reducing ends
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We report a traceless photocleavable linker for the automated glycan assembly of carbohydrates with free reducing ends. The reductive-labile functionality in the linker tolerates all commonly used reagents and protocols for automated glycan assembly, as demonstrated with the successful preparation of nine plant cell wall-related oligosaccharides, and is cleaved by hydrogenolysis.
- Wilsdorf,Schmidt,Bartetzko,Dallabernardina,Schuhmacher,Seeberger,Pfrengle
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supporting information
p. 10187 - 10189
(2016/08/18)
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- Palladium-catalyzed synthesis of aldehydes from aryl halides and tert-butyl isocyanide using formate salts as hydride donors
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An efficient one-pot palladium-catalyzed hydroformylation of aryl halides to produce aromatic aldehydes has been achieved, employing tert-butyl isocyanide as a C1 resource and formate salt as a hydride donor without any additional bases. Characterized by its mild reaction conditions, easy operation and lower toxicity, this reaction can tolerate a wide array of functional groups with moderate to excellent yields.
- Zhang, Ying,Jiang, Xiao,Wang, Jin-Mei,Chen, Jing-Lei,Zhu, Yong-Ming
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p. 17060 - 17063
(2015/03/30)
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- SUBSTITUTED 6, 7-DIALKOXY-3-ISOQUINOLINE DERIVATIVES AS INHIBITORS OF PHOSPHODIESTERASE 10 (PDE 10A)
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The invention relates to compounds of the formula or a pharmaceutically acceptable salt thereof, wherein R′, R1 through R7 and Ar are as defined herein. These compounds are useful as inhibitors of phosphodiesterase 10 (PDE10A) which are useful in treating central nervous system diseases such as psychosis and also in treating, for example, obesity, type II diabetes, metabolic syndrome, glucose intolerance, pain and ophthalmic diseases.
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- Signal transduction and amplification through enzyme-triggered ligand release and accelerated catalysis
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Signal transduction and signal amplification are both important mechanisms used within biological signalling pathways. Inspired by this process, we have developed a signal amplification methodology that utilises the selectivity and high activity of enzymes in combination with the robustness and generality of an organometallic catalyst, achieving a hybrid biological and synthetic catalyst cascade. A proligand enzyme substrate was designed to selectively self-immolate in the presence of the enzyme to release a ligand that can bind to a metal pre-catalyst and accelerate the rate of a transfer hydrogenation reaction. Enzyme-triggered catalytic signal amplification was then applied to a range of catalyst substrates demonstrating that signal amplification and signal transduction can both be achieved through this methodology.
- Goggins, Sean,Marsh, Barrie J.,Lubben, Anneke T.,Frost, Christopher G.
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p. 4978 - 4985
(2015/07/27)
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- Effect of Substituents and Stability of Transient Aluminum-Aminals in the Presence of Nucleophiles
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Disubstituted hydroxylamines are synthesized and used to form aluminum-amide complexes. These reagents mask carbonyl groups in situ via nucleophilic addition. The stability and utility of the aluminum-aminals are presented in the context of selectively controlling nucleophilic addition on substrates with multiple carbonyl groups.
- Barrios, Francis J.,Springer, Brannon C.,Hazlitt, Robert A.,Colby, David A.
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p. 175 - 180
(2015/05/05)
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