- Synthesis, isolation and characterization of cationic gold(I) N-heterocyclic carbene (NHC) complexes
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A number of cationic gold(I) complexes have been synthesized and found to be stabilized by the use of N-heterocyclic carbene ligands. These species are often employed as in situ-generated reactive intermediates in gold catalyzed organic transformations. An isolated, well-defined species was tested in gold-mediated carbene transfer reactions from ethyl diazoacetate. The Royal Society of Chemistry 2006.
- De Fremont, Pierre,Stevens, Edwin D.,Fructos, Manuel R.,Mar Diaz-Requejo,Perez, Pedro J.,Nolan, Steven P.
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- Noncanonical Heme Ligands Steer Carbene Transfer Reactivity in an Artificial Metalloenzyme**
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Changing the primary metal coordination sphere is a powerful strategy for tuning metalloprotein properties. Here we used amber stop codon suppression with engineered pyrrolysyl-tRNA synthetases, including two newly evolved enzymes, to replace the proximal histidine in myoglobin with Nδ-methylhistidine, 5-thiazoylalanine, 4-thiazoylalanine and 3-(3-thienyl)alanine. In addition to tuning the heme redox potential over a >200 mV range, these noncanonical ligands modulate the protein's carbene transfer activity with ethyl diazoacetate. Variants with increased reduction potential proved superior for cyclopropanation and N–H insertion, whereas variants with reduced Eo values gave higher S–H insertion activity. Given the functional importance of histidine in many enzymes, these genetically encoded analogues could be valuable tools for probing mechanism and enabling new chemistries.
- Dunkelmann, Daniel,Hayashi, Takahiro,Hilvert, Donald,Mittl, Peer R. E.,Ota, Yusuke,Pott, Moritz,Tinzl, Matthias
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- Silver-prompted carbonitration of acrylamides for the synthesis of nitrating oxindoles
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A silver-prompted carbonitration of alkenes involving concomitant direct C-H functionalization and C-N bond formation to synthesize nitrating oxindoles has been developed. The CR TH2 receptor antagonist skeleton can be obtained from one of the products with further modification.
- Wei, Xiao-Hong,Wu, Quan-Xiang,Yang, Shang-Dong
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- Catalyst design based on agostic interactions: Synthesis, characterization, and catalytic activity of bis(pyrazolyl)borate copper complexes
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Agostic interactions are often used to activate inert C-H bonds, and thus facilitate new reactions. We report the first example of designed catalysts based on the agostic interaction. Novel copper(i) complexes [BBN(pzx)2]Cu(PPh3)n (BBN = 9-borabicyclo[3.3.1]nonane; pzx = 3-substituted pyrazole; x = H, n = 2; x = Me, n = 1) and {[BBN(pziPr)2]Cu}2 have been synthesized and characterized. Single crystal studies of the three compounds show weak intramolecular C-H?Cu interactions which can be assigned as agostic or anagostic interactions. Catalytic studies of these complexes toward carbenoid insertion into N-H bonds indicate these weak interactions act as a "switch" which will be turned "on" if interacting with the substrate and "off" if eliminating the product and regenerating the weak interaction. The process of the "switch" turning "on" or "off", which is related to the catalytic effect, is found to be influenced by both steric effects and the solvent: a less sterically hindered catalyst in non-coordinating benzene results in high yield, while a more sterically hindered catalyst in coordinating THF results in relatively low yield.
- Cao, Hou-Ji,Zhao, Qianyi,Zhang, Qian-Fan,Li, Jiaxuan,Hamilton, Ewan J. M.,Zhang, Jie,Wang, Lai-Sheng,Chen, Xuenian
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- Metal Substitution Modulates the Reactivity and Extends the Reaction Scope of Myoglobin Carbene Transfer Catalysts
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Engineered myoglobins have recently emerged as promising scaffolds for catalyzing carbene-mediated transformations. In this work, we investigated the effect of altering the metal center and first-sphere coordination residue on the carbene transfer reactivity of myoglobin. To this end, we first established an efficient protocol for the recombinant expression of myoglobin variants incorporating metalloporphyrins with non-native metals, including second- and third-row transition metals (ruthenium, rhodium, iridium). Characterization of the cofactor-substituted myoglobin variants across three different carbene transfer reactions (cyclopropanation, N–H insertion, S–H insertion) revealed a major influence of the nature of the metal center, its oxidation state and first-sphere coordination environment on the catalytic activity, stereoselectivity, and/or oxygen tolerance of these artificial metalloenzymes. In addition, myoglobin variants incorporating manganese- or cobalt-porphyrins were found capable of catalyzing an intermolecular carbene C–H insertion reaction involving phthalan and ethyl α-diazoacetate, a reaction not supported by iron-based myoglobins and previously accessed only using iridium-based (bio)catalysts. These studies demonstrate how modification of the metalloporphyrin cofactor environment provides a viable and promising strategy to enhance the catalytic properties and extend the reaction scope of myoglobin-based carbene transfer catalysts. (Figure presented.).
- Sreenilayam, Gopeekrishnan,Moore, Eric J.,Steck, Viktoria,Fasan, Rudi
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- Photoredox-Catalyzed α-Aminomethyl Carboxylation of Styrenes with Sodium Glycinates: Synthesis of γ-Amino Acids and γ-Lactams
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A visible-light photoredox-catalyzed reductive α-aminomethyl carboxylation of styrenes with sodium glycinates and CO2 has been developed to synthesize a series of α,α-disubstituted γ-amino acids and γ-lactams with high efficiency and regioselectivity. Notably, CO2 released from the decarboxylation step can be reused for the subsequent carboxylation. Distinct from the previous reactions with the same type of substrates leading to simple decarboxylation and olefin hydroalkylation, this process involves additional CO2 sequestration, thus leading to olefin α-aminomethyl carboxylation. These findings not only provide new access to α,α-disubstituted γ-amino acids and γ-lactams but also serve as a proof of concept for CO2 reutilization in decarboxylation reactions.
- Zhou, Cong,Li, Miao,Sun, Jianwei,Cheng, Jiang,Sun, Song
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supporting information
p. 2895 - 2899
(2021/05/05)
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- Discovery and evolution of 12N-substituted aloperine derivatives as anti-SARS-CoV-2 agents through targeting late entry stage
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So far, there is still no specific drug against COVID-19. Taking compound 1 with anti-EBOV activity as the lead, fifty-four 12N-substituted aloperine derivatives were synthesized and evaluated for the anti-SARS-CoV-2 activities using pseudotyped virus model. Among them, 8a exhibited the most potential effects against both pseudotyped and authentic SARS-CoV-2, as well as SARS-CoV and MERS-CoV, indicating a broad-spectrum anti-coronavirus profile. The mechanism study disclosed that 8a might block a late stage of viral entry, mainly via inhibiting host cathepsin B activity rather than directly targeting cathepsin B protein. Also, 8a could significantly reduce the release of multiple inflammatory cytokines in a time- and dose-dependent manner, such as IL-6, IL-1β, IL-8 and MCP-1, the major contributors to cytokine storm. Therefore, 8a is a promising agent with the advantages of broad-spectrum anti-coronavirus and anti-cytokine effects, thus worthy of further investigation.
- Wang, Kun,Wu, Jia-Jing,Xin–Zhang,Zeng, Qing-Xuan,Zhang, Na,Huang, Wei-Jin,Tang, Sheng,Wang, Yan-Xiang,Kong, Wei-Jia,Wang, You-Chun,Li, Ying-Hong,Song, Dan-Qing
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- Direct, Site-Selective and Redox-Neutral α-C?H Bond Functionalization of Tetrahydrofurans via Quantum Dots Photocatalysis
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As one of the most ubiquitous bulk reagents available, the intrinsic chemical inertness of tetrahydrofuran (THF) makes direct and site-selective C(sp3)?H bond activation difficult, especially under redox neutral condition. Here, we demonstrate that semiconductor quantum dots (QDs) can activate α-C?H bond of THF via forming QDs/THF conjugates. Under visible light irradiation, the resultant alkoxyalkyl radical directly engages in radical cross-coupling with α-amino radical from amino C?H bonds or radical addition with alkene or phenylacetylene, respectively. In contrast to stoichiometric oxidant or hydrogen atom transfer reagents required in previous studies, the scalable benchtop approach can execute α-C?H bond activation of THF only by a QD photocatalyst under redox-neutral condition, thus providing a broad of value added chemicals starting from bulk THFs reagent.
- Chen, Bin,Ci, Rui-Nan,Huang, Cheng,Liu, Zan,Qiao, Jia,Song, Zi-Qi,Tung, Chen-Ho,Wu, Li-Zhu
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supporting information
p. 27201 - 27205
(2021/11/16)
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- Perovskite as Recyclable Photocatalyst for Annulation Reaction of N-Sulfonyl Ketimines
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A sustainable and cost-effective manner for the photocatalytic annulation reaction of N-sulfonyl ketimines with N-arylglycines to synthesize imidazolidine-fused sulfamidates (31 examples) by employing CsPbBr3 as a heterogeneous photocatalyst has been developed. The catalyst CsPbBr3 can be simply recovered from the reaction mixture and reused at least five times without an obvious reduction in its photocatalytic reactivity, exhibiting a high catalyst economic feature.
- Chen, Xiaolan,Qu, Lingbo,Shi, Anzai,Sun, Kai,Yu, Bing,Zhao, Yufen
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supporting information
(2022/01/04)
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- Water-Involved Ring-Opening of 4-Phenyl-1,2,4-triazoline-3,5-dione for “Photo-Clicked” Access to Carbamoyl Formazan Photoswitches In Situ
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Cyclic azodicarbonyl derivatives, particularly 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), commonly serve as arenophile, dienophile, enophile and electrophile. Perplexed by its instability in aqueous environment, there are few studies focused on the transient intermediate produced by hydrolysis of PTAD to achieve synthetic significance. Herein, we describe a “photo-click” method that involves nitrile imine (NI) from diarylsydnone to capture the diazenecarbonyl-phenyl-carbamic acid (DACPA) generated by water-promoted ring-opening of PTAD. DFT calculation reveal that H-bonding interactions between PTAD and water are vital to form DACPA which exhibited an umpolung effect during ligation by nature bond orbit (NBO) analysis. The ultra-fast ligation resulted in carbamoyl formazans, as a unique Z?E photo-switchable linker on target molecules, including peptide and drugs, with excellent anti-fatigue performance. This strategy is showcased to construct highly functionalized carbamoyl formazans in situ for photo-pharmacology and material studies, which also expands the chemistry of PTAD in aqueous media.
- Deng, Pengchi,Du, Guangxi,Jiang, Shichao,Shen, Xin,Su, Zhishan,Xie, Xinyu,Yu, Zhipeng,Zhang, Yan,Zhao, Xiaohu,Zheng, Yuanqin,Zhou, Yuqiao
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supporting information
(2021/12/22)
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- Selective carbene transfer to amines and olefins catalyzed by ruthenium phthalocyanine complexes with donor substituents
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Electron-rich ruthenium phthalocyanine complexes were evaluated in carbene transfer reactions from ethyl diazoacetate (EDA) to aromatic and aliphatic olefins as well as to a wide range of aromatic, heterocyclic and aliphatic amines for the first time. It was revealed that the ruthenium octabutoxyphthalocyanine carbonyl complex [(BuO)8Pc]Ru(CO) is the most efficient catalyst converting electron-rich and electron-poor aromatic olefins to cyclopropane derivatives with high yields (typically 80-100%) and high TON (up to 1000) under low catalyst loading and nearly equimolar substrate/EDA ratio. This catalyst shows a rare efficiency in the carbene insertion into amine N-H bonds. Using a 0.05 mol% catalyst loading, a high amine concentration (1 M) and 1.1 eq. of EDA, a number of structurally divergent amines were selectively converted to mono-substituted glycine derivatives with up to quantitative yields and turnover numbers reaching 2000. High selectivity, large substrate scope, low catalyst loading and practical reaction conditions place [(BuO)8Pc]Ru(CO) among the most efficient catalysts for the carbene insertion into amines.
- Cailler, Lucie P.,Kroitor, Andrey P.,Martynov, Alexander G.,Gorbunova, Yulia G.,Sorokin, Alexander B.
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supporting information
p. 2023 - 2031
(2021/02/26)
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- Ethyl cellulose derived porous iron@N-doped carbon material for N–H carbene insertion reaction
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A newly developed, facile and sustainable strategy, in which zinc salt, melamine and ethyl cellulose are applied as pore-forming agent, nitrogen and carbon source respectively, has been disclosed for the synthesis of Fe/N-codoped carbon materials. This material exhibits excellent catalytic efficiency towards N–H carbene insertion reaction for the synthesis of unnatural amino acid derivatives. Fe/FeOx nanoparticles tranfer electrons to N-doped carbon owing to the Mott-Schottky Effect, which is beneficial to the formation of iron carbene intermediate. N-doping can offer more Lewis base sites, which promotes the proton transfer process. Fe/FeOx nanoparticles are coated with graphitic carbon, thereby avoiding the loss and deactivation of iron sites in this material. Therefore, this material can be reused at least four times without significant loss in activity.
- Lin, Yamei,Wang, Fei,Lu, Guo-Ping,Zhang, Xing
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- COMPOUND USED AS AUTOPHAGY REGULATOR, AND PREPARATION METHOD THEREFOR AND USES THEREOF
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It is related to compounds used as autophagy modulators and a method for preparing and using the same, specifically providing a compound of general formula (I), or pharmaceutically acceptable salts thereof, which is a type of autophagy modulators, particularly mammalian ATG8 homologues modulators.
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Paragraph 0310-0311
(2020/07/07)
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- Photoinduced iodine-mediated tandem dehydrogenative Povarov cyclisation/C-H oxygenation reactions
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We report metal-free, photoinduced aerobic tandem dehydrogenative Povarov cyclisation/Csp3-H oxygenation reactions between N-aryl glycine esters and α-substituted styrenes, which efficiently lead to 4,4-disubstituted dihydroquinoline-3-ones under mild conditions. The reactions are mediated by iodine along with visible light irradiation, which allows for the in situ generation of the essential Br?nsted acid HI, to catalyse the key imine [4+2]-cycloaddition.
- Brasholz, Malte,Schendera, Eva,Villinger, Alexander
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supporting information
p. 6912 - 6915
(2020/10/02)
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- Copper-Catalyzed Annulation of Oxime Acetates with α-Amino Acid Ester Derivatives: Synthesis of 3-Sulfonamido/Imino 4-Pyrrolin-2-ones
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A copper-catalyzed annulation of oxime acetates and α-amino acid ester derivatives for the easy preparation of 4-pyrrolin-2-ones bearing a 3-amino group has been developed. This process features the oxidation of amines with oxime esters as the internal oxidant to produce the active 1,3-dinucleophilic and 1,2-dielectrophilic species concurrently. The subsequent nucleophilic cyclization realizes the efficient construction of 4-pyrrolin-2-one derivatives.
- Miao, Chun-Bao,Zheng, An-Qi,Zhou, Li-Jin,Lyu, Xinyu,Yang, Hai-Tao
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supporting information
p. 3381 - 3385
(2020/04/21)
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- Al(OTf)3-Catalyzed Tandem Coupling Reaction between N,N-Disubstituted Aminomalonitriles and Substituted Arenes: a Synthesis of 1-Cyano-bisindolylmethane Analogues≠
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A synthesis of 1-cyano-bisindolylmethane analogues via an Al(OTf)3-catalyzed tandem coupling reaction between N,N-disubstituted aminomalonitriles and substituted arenes has been developed. This method not only provides an alternative synthetic strategy for the synthesis of corresponding functional molecules, but also enriches the volume of bisarylmethanes library to facilitate related functional studies. (Figure presented.).
- Lei, Lin-Sheng,Wang, Bo-Wen,Jin, Da-Ping,Gao, Zhu-Peng,Huan-Liang,Wang, Shao-Hua,Xu, Xue-Tao,Zhang, Kun,Zhang, Xiao-Yun
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supporting information
p. 2870 - 2875
(2020/06/17)
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- Unnatural α-Amino Acid Synthesized through α-Alkylation of Glycine Derivatives by Diacyl Peroxides
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We have developed a protocol for catalyst- and additive-free α-alkylation reactions of glycine derivatives with diacyl peroxides, which proceed by a pathway involving addition of alkyl radicals to imine intermediates. The diacyl peroxide substrate acts as both alkylation agent and oxidizing agent, which means it is atom-economical. It was applied to various glycine derivatives, dipeptides, and a 3,4-dihydroquinoxalin-2(1H)-one derivative and could be carried out on a gram scale, indicating its utility for late-stage functionalization.
- Tian, Hao,Xu, Wentao,Liu, Yuxiu,Wang, Qingmin
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supporting information
p. 5005 - 5008
(2020/07/04)
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- Preparation method of N-aryl glycine ester derivative
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The invention relates to a preparation method of an N-aryl glycine ester derivative. The invention aims to solve the problems of complex steps and environmental pollution in the existing method for synthesizing the N-aryl glycine ester derivative. The preparation method comprises the following steps: dissolving an aryl primary amine compound, ethyl diazoacetate, a reaction aid and a photocatalystin an organic solvent at room temperature, uniformly mixing, reacting under a blue LEDs lamp, carrying out reduced pressure distillation to remove the solvent, and separating and purifying to obtain the product. The problems of high energy consumption, high cost and environmental pollution caused by high temperature, biocatalyst or metal organic framework required by the synthesis of the existingN-aryl glycine ester derivative are solved. A route for synthesizing the N-arylglycine ester derivative, which is green, efficient, mild in condition, simple in method, convenient to operate and highin yield, is found, and the method is applied to the field of organic synthesis.
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Paragraph 0029-0034
(2020/07/12)
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- Catalytic Selective Oxidative Coupling of Secondary N-Alkylanilines: An Approach to Azoxyarene
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Azoxyarenes are among important scaffolds in organic molecules. Direct oxidative coupling of primary anilines provides a concise fashion to construct them. However, whether these scaffolds can be prepared from secondary N-alkylanilines is not well explored. Here, we present a catalytic selective oxidative coupling of secondary N-alkylaniline to afford azoxyarene with tungsten catalyst under mild conditions. In addition, azoxy can be viewed as a bioisostere of alkene and amide. Several "azoxyarene analogues" of the corresponding bioactive alkenes and amides showed comparable promising anticancer activities.
- Ke, Lei,Zhu, Guirong,Qian, Hui,Xiang, Guangya,Chen, Qin,Chen, Zhilong
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supporting information
p. 4008 - 4013
(2019/06/04)
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- Structure-activity relationships and mechanistic studies of novel mitochondria-targeted, leishmanicidal derivatives of the 4-aminostyrylquinoline scaffold
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A new class of quinoline derivatives, bearing amino chains at C-4 and a styryl group at C-2, were tested on Leishmania donovani promastigotes and axenic and intracellular Leishmania pifanoi amastigotes. The introduction of the C-4 substituent improves the activity, which is due to interference with the mitochondrial activity of the parasite and its concomitant bioenergetic collapse by ATP exhaustion. Some compounds show a promising antileishmanial profile, with low micromolar or submicromolar activity on promastigote and amastigote forms and a good selectivity index.
- Staderini, Matteo,Piquero, Marta,Abengózar, María ángeles,Nachér-Vázquez, Montserrat,Romanelli, Giulia,López-Alvarado, Pilar,Rivas, Luis,Bolognesi, Maria Laura,Menéndez, J. Carlos
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- Reductive Molybdenum-Catalyzed Direct Amination of Boronic Acids with Nitro Compounds
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The synthesis of aromatic amines is of utmost importance in a wide range of chemical contexts. We report a direct amination of boronic acids with nitro compounds to yield (hetero)aryl amines. The novel combination of a dioxomolybdenum(VI) catalyst and triphenylphosphine as inexpensive reductant has revealed to be decisive to achieve this new C?N coupling. Our methodology has proven to be scalable, air and moisture tolerant, highly chemoselective and engages both aliphatic and aromatic nitro compounds. Moreover, this general and step-economical synthesis of aromatic secondary amines showcases orthogonality to other aromatic amine syntheses as it tolerates aryl halides and carbonyl compounds.
- Suárez-Pantiga, Samuel,Hernández-Ruiz, Raquel,Virumbrales, Cintia,Pedrosa, María R.,Sanz, Roberto
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supporting information
p. 2129 - 2133
(2019/01/25)
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- Exploring the Conformation of Mixed Cis- Trans α,β-Oligopeptoids: A Joint Experimental and Computational Study
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The synthesis and conformational preferences of a set of new synthetic foldamers that combine both the α,β-peptoid backbone and side chains that alternately promote cis- and trans-amide bond geometries have been achieved and addressed jointly by experiment and molecular modeling. Four sequence patterns were thus designed and referred to as cis-β-trans-α, cis-α-trans-β, trans-β-cis-α, and trans-α-cis-β. α- and βNtBu monomers were used to enforce cis-amide bond geometries and α- and βNPh monomers to promote trans-amides. NOESY and molecular modeling reveal that the trans-α-cis-β and cis-β-trans-α tetramers show a similar pattern of intramolecular weak interactions. The same holds for the cis-α-trans-β and trans-β-cis-α tetramers, but the interactions are different in nature than those identified in the trans-α-cis-β-based oligomers. Interestingly, the trans-α-cis-β peptoid architecture allows establishment of a larger amount of structure-stabilizing intramolecular interactions.
- Dumonteil, Geoffrey,Bhattacharjee, Nicholus,Angelici, Gaetano,Roy, Olivier,Faure, Sophie,Jouffret, Laurent,Jolibois, Franck,Perrin, Lionel,Taillefumier, Claude
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p. 6382 - 6396
(2018/06/26)
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- CATHEPSIN-D AND ANGIOGENESIS INHIBITORS AND COMPOSITIONS THEREOF FOR TREATING BREAST CANCER
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The invention relates to Cathepsin-D and angiogenesis inhibitors and compositions thereof for treating breast cancer. More particularly, the invention relates to the design and synthesis of inhibitors of Cathepsin D which exhibits antiproliferative activity and also inhibits angiogenesis. The present invention also relates to the compositions thereof for treating breast cancer.
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Page/Page column 18
(2018/09/28)
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- Functionalization of N-arylglycine esters: Electrocatalytic access to C-C bonds mediated by n-Bu4NI
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An efficient electrocatalytic functionalization of N-arylglycine esters is reported. The protocol proceeds in an undivided cell under constant current conditions employing the simple, cheap and readily available n-Bu4NI as the mediator. In addition, it is demonstrated that the mediated process is superior to the direct electrochemical functionalization.
- Luo, Mi-Hai,Jiang, Yang-Ye,Xu, Kun,Liu, Yong-Guo,Sun, Bao-Guo,Zeng, Cheng-Chu
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supporting information
p. 499 - 505
(2018/03/21)
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- Arylamino containing hydroxamic acids as potent urease inhibitors for the treatment of Helicobacter pylori infection
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A novel series of aniline-containing hydroxamic acids were designed, synthesized and evaluated as anti-virulence agents for the treatment of gastritis and gastric ulcer caused by Helicobacter pylori. In vitro enzyme-based screen together with in vivo assays and structure?activity relationship (SAR) studies led to the discovery of three potent urease inhibitors 3-(3,5-dichlorophenylamino)–N-hydroxypropanamide (3a), 3-(2-chlorophenylamino)–N-hydroxypropanamide (3d) and 3-(2,4-dichlorophenylamino)–N-hydroxypropanamide (3n). Compounds 3a, 3d and 3n showed excellent urease inhibition with IC50 values 0.043 ± 0.005, 0.055 ± 0.008 and 0.018 ± 0.002 μM, and significantly depressed gastritis developing at the dose of 32 mg/kg b. i.d with eradication rates of H. pylori reaching 92.3, 84.6 and 100%, respectively. Preliminary safety studies (acute toxicity in mice) disclosed that 3a, 3d and 3n was well-tolerated in KM mice with LD50s of 2982.8, 3349.4 and 3126.9 mg/kg, respectively. Collectively, the data obtained in this study indicate that 3a, 3d and 3n, in particular 3n, could considered as promising candidates for the potential treatment of H. pylori caused gastritis and gastric ulcer, and hence merit further studies.
- Liu, Qi,Shi, Wei-Kang,Ren, Shen-Zhen,Ni, Wei-Wei,Li, Wei-Yi,Chen, Hui-Min,Liu, Pei,Yuan, Jing,He, Xiao-Su,Liu, Jia-Jia,Cao, Peng,Yang, Pu-Zhen,Xiao, Zhu-Ping,Zhu, Hai-Liang
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p. 126 - 136
(2018/07/13)
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- Copper Triflate Catalyzed Oxidative α-Allylation of Glycine Derivatives
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Copper triflate catalyzed oxidative C-H functionalization of glycine derivatives with allyltributyltin has been established using oxygen or tert -butyl hydroperoxide as oxidant. Various glycine esters and glycine amides were suitable substrates for this oxidative allylation reaction and afforded the desired homoallylic amines in moderate to good yields.
- Chen, Ting-Ting,Cai, Chun
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supporting information
p. 1368 - 1372
(2017/06/27)
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- Method for synthesizing alpha-amino-acid ester compound through catalytic oxidation one-step process
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The invention belongs to the technical field of organic chemical industry and discloses a method for synthesizing an alpha-amino-acid ester compound through a catalytic oxidation one-step process. The method comprises the following steps: (1) reacting a vinyl ether/amine compound or alkene amide compound with an amine compound in an organic solvent under a synergic effect of a catalyst and an oxidizing agent; and (2) separating and purifying a product after the ending of the reaction, thereby acquiring the alpha-amino-acid ester compound. The method is simple and safe in operation, the compound is synthesized within one step, an ester bond is acquired in a reaction process, a nontoxic pollution-free peroxide is used as an oxidizing agent, the raw materials are low in cost and are easily acquired and the alpha-amino-acid ester compound has wide adaptability to functional groups, wide adaptability to substrates, environmental protection and an excellent industrial application prospect.
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Paragraph 0082; 0083; 0089
(2017/09/01)
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- Access to α-Amino Acid Esters through Palladium-Catalyzed Oxidative Amination of Vinyl Ethers with Hydrogen Peroxide as the Oxidant and Oxygen Source
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A novel and convenient palladium catalytic system for the synthesis of α-amino acid esters from simple starting materials is reported. Hydrogen peroxide not only acts as the green oxidant, but also as the oxygen source. This strategy for the conversion of amines and vinyl ethers into highly functionalized and structurally diverse α-amino acid esters is characterized by the simplicity of the experimental procedure, mild reaction conditions, high atom economy, scalability, and practicability.
- Ouyang, Lu,Li, Jianxiao,Zheng, Jia,Huang, Jiuzhong,Qi, Chaorong,Wu, Wanqing,Jiang, Huanfeng
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supporting information
p. 15926 - 15930
(2017/11/23)
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- Dual role of Cu2O nanocubes as templates and networking catalysts for hollow and microporous Fe-porphyrin networks
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Cu2O nanocubes were used for the synthesis of hollow and microporous Fe porphyrin networks (H-MFePN). In this synthesis, Cu2O nanocubes performed not only as networking catalysts but also as shape controlling templates. MFePN were formed on the surface of the Cu2O nanocubes through azide-alkyne cycloaddition of tetrakis(4-ethynylphenyl) Fe-porphyrin with 1,4-diazidobenzene. H-MFePN showed excellent catalytic activities in carbene insertion into N-H bonds, maintaining their activities during five recycle tests.
- Kang, Daye,Ko, Ju Hong,Choi, Jaewon,Cho, Kyoungil,Lee, Sang Moon,Kim, Hae Jin,Ko, Yoon-Joo,Park, Kang Hyun,Son, Seung Uk
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supporting information
p. 2598 - 2601
(2017/03/09)
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- Unexpected formation of a μ-carbido diruthenium(IV) complex during the metalation of phthalocyanine with Ru3(CO)12 and its catalytic actIVity in carbene transfer reactions
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A μ-carbido diruthenium(iv) phthalocyanine complex was prepared for the first time from the free-base octabutoxyphthalocyanine by direct metalation with Ru3(CO)12. The first examples of the catalytic activity of Ru(iv) binuclear phthalocyanines were demonstrated by the cyclopropanation of aromatic olefins and carbene insertion into the N-H bonds of aromatic or aliphatic amines with turnover numbers of 680-1000 and 580-1000, respectively.
- Kroitor, Andrey P.,Cailler, Lucie P.,Martynov, Alexander G.,Gorbunova, Yulia G.,Tsivadze, Aslan Yu.,Sorokin, Alexander B.
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supporting information
p. 15651 - 15655
(2017/12/02)
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- Carbene X[sbnd]H bond insertions catalyzed by copper(I) macrocyclic pyridine-containing ligand (PcL) complexes
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A catalytic system comprising copper(I) and macrocyclic pyridine-containing ligands (Pc-L) proves capable of promoting carbene Si[sbnd]H bond insertions using diazo compounds as the carbene source. This catalytic system showed broad scope and a remarkable robustness as indicated by high TON numbers (up to 30000). Moreover, the use of enynones as carbene sources proved also feasible in hydrosilane insertion using this catalytic system. Finally, the insertion in O[sbnd]H and N[sbnd]H bonds of phenols and anilines, respectively, has been also demonstrated.
- Tseberlidis, Giorgio,Caselli, Alessandro,Vicente, Rubén
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supporting information
p. 1 - 5
(2017/03/01)
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- NH insertion reactions catalyzed by reusable water-soluble ruthenium(II)-hm-phenyloxazoline complex
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A water-soluble Ru(II)-hm-pheox complex was efficiently catalyzed NH insertion of EDA with a broad class of amine derivatives in water/ether biphasic medium to deliver the biologically active precursors α-aminoester products with excellent yields (up to >99%). The products were separated by decantation and the catalyst was washed and reused several times (at least 8 times) without any specific loss of its catalytic activity. The plausible mechanism of the reaction was explained. Additionally, In case of ethylene diamine, the NH insertion product could be transformed to biological active piperazinone compound in high yield. The asymmetric version of this catalytic reaction is under investigation.
- Abu-Elfotoh, Abdel-Moneim
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supporting information
p. 4750 - 4754
(2017/11/29)
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- Engineering of RuMb: Toward a Green Catalyst for Carbene Insertion Reactions
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The small, stable heme protein myoglobin (Mb) was modified through cofactor substitution and mutagenesis to develop a new catalyst for carbene transfer reactions. The native heme was removed from wild-type Mb and several Mb His64 mutants (H64D, H64A, H64V), and the resulting apoproteins were reconstituted with ruthenium mesoporphyrin IX (RuMpIX). The reconstituted proteins (RuMb) were characterized by UV-vis and circular dichroism spectroscopy and were used as catalysts for the N-H insertion of aniline derivatives and the cyclopropanation of styrene derivatives. The best catalysts for each reaction were able to achieve turnover numbers (TON) up to 520 for the N-H insertion of aniline, and 350 TON for the cyclopropanation of vinyl anisole. Our results show that RuMb is an effective catalyst for N-H insertion, with the potential to further increase the activity and stereoselectivity of the catalyst in future studies. Compared to native Mb ("FeMb"), RuMb is a more active catalyst for carbene transfer reactions, which leads to both heme and protein modification and degradation and, hence, to an overall much-reduced lifetime of the catalyst. This leads to lower TONs for RuMb compared to the iron-containing analogues. Strategies to overcome this limitation are discussed. Finally, comparison is also made to FeH64DMb and FeH64AMb, which have not been previously investigated for carbene transfer reactions.
- Wolf, Matthew W.,Vargas, David A.,Lehnert, Nicolai
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p. 5623 - 5635
(2017/05/22)
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- Cs2CO3-Promoted Direct N-Alkylation: Highly Chemoselective Synthesis of N-Alkylated Benzylamines and Anilines
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Herein is described an efficient and chemoselective method for the synthesis of diversely substituted secondary amines in yields up to 98 %. Direct mono-N-alkylation of primary benzylamines and anilines with a wide range of alkyl halides is promoted by a cesium base in the absence of any additive or catalyst. The basicity and solubility of cesium carbonate in anhydrous N,N-dimethylformamide not only enables mono-N-alkylation of primary amines but also suppresses undesired dialkylation of the desired amines.
- Castillo, Juan-Carlos,Orrego-Hernández, Jessica,Portilla, Jaime
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p. 3824 - 3835
(2016/08/20)
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- Iron-catalyzed direct α-arylation of α-amino carbonyl compounds with indoles
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A mild and general α-arylation of α-amino carbonyls with indoles catalyzed by Fe(ClO4)3 has been developed. C-H activation is smoothly fulfilled by using TBHP as the oxidant with good yields. Two hydrogen dissociations make this transformation more environmentally benign because of high atom efficiency.
- Zhang, Yan,Ni, Minjie,Feng, Bainian
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supporting information
p. 1550 - 1554
(2016/02/10)
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- AROMATIC COMPOUND
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Provided is a novel aromatic ring compound having a GPR40 agonist activity and a GLP-1 secretagogue action. A compound represented by the formula: wherein each symbol is as described in the DESCRIPTION, or a salt thereof has a GPR40 agonist activity and a GLP-1 secretagogue action, is useful for the prophylaxis or treatment of cancer, obesity, diabetes, hypertension, hyperlipidemia, cardiac failure, diabetic complications, metabolic syndrome, sarcopenia and the like, and affords superior efficacy.
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Paragraph 1079; 1080
(2016/05/19)
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- A series of robust metal-porphyrinic frameworks based on rare earth clusters and their application in N-H carbene insertion
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We herein report a series of microporous metal-porphyrinic frameworks (MPFs), denoted as NUPF-2M, based on rare earth (RE) clusters. NUPF-2M represent the first examples of RE cluster-based MPFs, possessing a rarely seen shp-a topology and exhibiting high thermal and thermal stabilities. After a post-metallization process with FeCl3, NUPF-2M is catalytically active as an efficient heterogeneous catalyst for intermolecular N-H carbene insertion.
- Xu, Lei,Zhai, Meng-Ke,Wang, Fei,Sun, Lin,Du, Hong-Bin
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p. 17108 - 17112
(2016/11/13)
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- MYOGLOBIN-BASED CATALYSTS FOR CARBENE TRANSFER REACTIONS
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Methods are provided for carrying out carbene transfer transformations such as olefin cyclopropanation reactions, carbene heteroatom-H insertion reactions (heteroatom = N, S, Si), sigmatropic rearrangement reactions, and aldehyde olefination reactions with high efficiency and selectivity by using a novel class of myoglobin-based biocatalysts. These methods are useful for the synthesis of a variety of organic compounds which contain one or more new carbon-carbon or carbon-heteroatom (N, S, or Si) bond. The methods can be applied for conducting these transformations in vitro (i.e., using the biocatalyst in isolated form) and in vivo (i.e., using the biocatalyst in a whole cell system).
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Paragraph 00278; 00279
(2016/06/14)
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- Catechols and 3-hydroxypyridones as inhibitors of the DNA repair complex ERCC1-XPF
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Catechol-based inhibitors of ERCC1-XPF endonuclease activity were identified from a high-throughput screen. Exploration of the structure-activity relationships within this series yielded compound 13, which displayed an ERCC1-XPF IC50 of 0.6 μM, high selectivity against FEN-1 and DNase I and activity in nucleotide excision repair, cisplatin enhancement and γH2AX assays in A375 melanoma cells. Screening of fragments as potential alternatives to the catechol group revealed that 3-hydroxypyridones are able to inhibit ERCC1-XPF with high ligand efficiency, and elaboration of the hit gave compounds 36 and 37 which showed promising ERCC1-XPF IC50 values of 10 μM.
- Chapman, Timothy M.,Gillen, Kevin J.,Wallace, Claire,Lee, Maximillian T.,Bakrania, Preeti,Khurana, Puneet,Coombs, Peter J.,Stennett, Laura,Fox, Simon,Bureau, Emilie A.,Brownlees, Janet,Melton, David W.,Saxty, Barbara
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supporting information
p. 4097 - 4103
(2015/11/03)
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- Hemin-Catalyzed, Cyclodextrin-Assisted Insertion of Carbenoids into N-H Bonds
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An aqueous hemin-catalyzed, cyclodextrin-assisted N-H insertion reaction of α-diazo ester into aromatic amines is described here. This aqueous catalytic system showed good compatibility with various arylamines, with yields up to 96%. A size-controlled reaction phenomenon by different cyclodextrins (CDs) was also observed when ethyl diazoacetate (EDA) was used. The reaction mechanism was also preliminarily proposed on the basis of designed control experiments.
- Xu, Xiaofei,Li, Chang,Tao, Zhihao,Pan, Yuanjiang
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supporting information
p. 3341 - 3345
(2015/11/03)
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- A fully recyclable heterogenized Cu catalyst for the general carbene transfer reaction in batch and flow
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A polystyrene-linked tris(triazolyl)methanecopper(i) cationic catalyst operates under heterogeneous conditions for the reaction of ethyl diazoacetate (EDA) with an array of substrates. Carbon-hydrogen as well as X-H (X = O, N) functionalization derived from the formal transfer of the carbene moiety (:CHCO2Et) from the copper center and subsequent insertion have been achieved, the reactions permitting repeated catalyst recycling and reuse. The addition of the same carbene unit to benzene leading to a cycloheptatriene derivative (Büchner reaction) or to phenylacetylene (cyclopropenation) took place at similar rates to the insertion processes and with the same catalyst recyclability. The use of this heterogenized cationic Cu catalyst in continuous flow has also been implemented. Key characteristics of the flow process are its high and constant turnover frequency (TOF) (residence times of 1 min still lead to full conversion in the reaction with ethanol after 48 h operation) and its suitability for the sequential performance of different types of carbene transfer reactions with a simple and affordable experimental setup.
- Maestre, Lourdes,Ozkal, Erhan,Ayats, Carles,Beltrn, lvaro,Daz-Requejo, M. Mar,Prez, Pedro J.,Perics, Miquel A.
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p. 1510 - 1515
(2015/02/05)
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- Myoglobin-catalyzed intermolecular carbene N-H insertion with arylamine substrates
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Engineered variants of the heme-containing protein myoglobin can efficiently catalyze the insertion of α-diazo esters into the N-H bond of arylamines, featuring a combination of high chemoselectivity, elevated turnover numbers, and broad substrate scope.
- Sreenilayam, Gopeekrishnan,Fasan, Rudi
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supporting information
p. 1532 - 1534
(2015/08/03)
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- PYRAZOLO[3,4-D]PYRIMIDIN-4(5H)-ONE DERIVATIVES AS PDE9 INHIBITORS
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A compound of the general formula (I) wherein R1 is selected from the group consisting of phenyl unsubstituted or substituted with 1 to 3 substituents selected from F, Cl, Br, I, CN, -O-C1-C3-alkyl, fluorinated -O-C1-C3-alkyl, -(CH2)mOH and 5-membered heterocyclic group with 1 or 2 heteroatoms selected from N, O and S; and 6- or 10-membered heteroaryl with 1 to 3 heteroatoms selected from O, N and S; R2 and R3 independently of each other represent H atom or straight or branched C1-C3 alkyl; R4 is selected from the group consisting of 4- to 6- membered cycloalkyl, wherein one of carbon atoms can be replaced by O atom, and which is unsubstituted or substituted with one or two halogen atoms,and straight or branched C1-C4 alkyl; Q represents a bond or C1-C3-alkylene, which can be optionally substituted by one to three C1-C3-alkyls; X is selected from the group consisting of O, NR5, and S(O)p; R5 represents H atom or C1-C3alkyl; m is 1, 2 or 3; p is 0, 1 or 2; and salts thereof, for use as a medicament, in particular for treating cognitive function disorders and neurodegenerative diseases.
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Page/Page column 28
(2014/02/16)
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- Cytochrome P450-catalyzed insertion of carbenoids into N-H bonds
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Expanding nature's catalytic repertoire to include reactions important in synthetic chemistry will open new opportunities for 'green' chemistry and biosynthesis. We demonstrate the first enzyme-catalyzed insertion of carbenoids into N-H bonds. This type of bond disconnection, which has no counterpart in nature, can be mediated by variants of the cytochrome P450 from Bacillus megaterium. The N-H insertion reaction takes place in water, provides the desired products in 26-83% yield, forms the single addition product exclusively, and does not require slow addition of the diazo component.
- Wang, Z. Jane,Peck, Nicole E.,Renata, Hans,Arnold, Frances H.
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p. 598 - 601
(2014/01/17)
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- Metal-free reductive cleavage of C-N and S-N bonds by photoactivated electron transfer from a neutral organic donor
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A photoactivated neutral organic super electron donor cleaves challenging arenesulfonamides derived from dialkylamines at room temperature. It also cleaves a)ArC-NR and b)ArN-C bonds. This study also highlights the assistance given to these cleavage reactions by the groups attached to N in (a) and to C in (b), by lowering LUMO energies and by stabilizing the products of fragmentation. Radical fragmentations: Electron transfer from the photoactivated neutral electron donor 1 delivers high yields of S-N and C-N cleavage products for a range of nitrogen-containing species. These reactions proceed at room temperature and under mild reaction conditions in the absence of any metal reagents. DMF=N,N-dimethylformamide, Ts=4-toluenesulfonyl.
- O'Sullivan, Steven,Doni, Eswararao,Tuttle, Tell,Murphy, John A.
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p. 474 - 478
(2014/01/23)
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- P-Tolylimido rhenium(v) complexes-synthesis, X-ray studies, spectroscopic characterization, DFT calculations and catalytic activity
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Novel p-tolylimido rhenium(v) complexes trans-(Cl,Cl)-[Re(p-NC 6H4CH3)Cl2(py-2-COO)(PPh 3)]·MeCN (1a), trans-(Cl,Cl)-[Re(p-NC6H 4CH3)Cl2(py-2-COO)(PPh3)] (1b), trans-(Br,Br)-[Re(p-NC6H4CH3)Br 2(py-2-COO)(PPh3)] (2), cis-(Cl,Cl)-[Re(p-NC 6H4CH3)Cl2(py-2-COO)(PPh 3)] (3), cis-(Br,Br)-[Re(p-NC6H4CH 3)Br2(py-2-COO)(PPh3)]·H2O (4), trans-(Cl,Cl)-[Re(p-NC6H4CH3)Cl 2(OMe)] (5) and trans-(Br,Br)-[Re(p-NC6H 4CH3)Br2(OMe)(PPh3) 2]·1/2H2O (6) were synthesized. The compounds were identified by elemental analysis, IR, NMR (1H, 13C and 31P), UV-Vis spectroscopy and X-ray crystallography. Calculations at the DFT level were undertaken in order to elucidate the structural, spectroscopic and bonding properties of the trans-(Cl,Cl) and cis-(Cl,Cl) isomers of [Re(p-NC6H4CH3)Cl 2(py-2-COO)(PPh3)]. In the first step, extended tests of the ability of different DFT methods (B3LYP, BP86, and PBE1PBE) were performed to find the best overall performer in describing the geometry of the imido Re(v) complexes; then, the electronic spectra of the trans and cis isomers of [Re(p-NC6H4CH3)Cl2(py-2-COO) (PPh3)] were investigated at the TDDFT level employing the PBE1PBE functional. Additional information about bonding in the compounds [Re(p-NC 6H4CH3)Cl2(py-2-COO)(PPh 3)] was obtained by NBO analysis. The catalytic activity of the complexes incorporating the picolinate ligand was studied and compared in the synthesis of N-substituted ethyl glycine esters from ethyl diazoacetate and amines.
- Machura, Barbara,Gryca, Izabela,Malecki, Jan Grzegorz,Alonso, Francisco,Moglie, Yanina
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p. 2596 - 2610
(2014/02/14)
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- 1-Methylimidazolium tetrafluoroborate [Hmim][BF4]: An efficient acidic ionic liquid catalyst for insertion of α-diazo compounds into the N-H bonds of amines
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The reusable acidic ionic liquid, 1-methylimidazolium tetrafluoroborate [Hmim][BF4], was found to be an effective catalyst for the insertion of α-diazoacetate into the N-H bonds of amines. The corresponding products were obtained in good yields and short reaction times via a simple procedure. The catalyst could be recycled and reused without any noticeable decrease in its activity.
- Akbari, Jafar,Ebrahimi, Ali,Heydari, Akbar
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p. 5417 - 5419
(2014/12/11)
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- Synthesis, structural characterization, reactivity, and catalytic properties of copper(I) complexes with a series of tetradentate tripodal tris(pyrazolylmethyl)amine ligands
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Novel tris(pyrazolylmethyl)amine ligands TpaMe3, Tpa*,Br, and TpaBr3 have been synthesized and structurally characterized. The coordination chemistries of these three new tetradentate tripodal ligands and the already known Tpa and Tpa* have been explored using different copper(I) salts as starting materials. Cationic copper(I) complexes [TpaxCu]PF6 (1-4) have been isolated from the reaction of [Cu(NCMe)4]PF6 and 1 equiv of the ligand. Complexes 2 (Tpax = Tpa*) and 3 (Tpax = TpaMe3) have been characterized by X-ray studies. The former is a 1D helical coordination polymer, and the latter is a tetranuclear helicate. In both structures, the Tpax ligand adopts a μ2: κ2:κ1-coordination mode. However, in solution, all of the four complexes form fluxional species. When CuI is used as the copper(I) source, neutral compounds 5-8 have been obtained. Complexes 6-8 exhibit a 1:1 metal-to-ligand ratio, whereas 5 presents 2:1 stoichiometry. Its solid-state structure has been determined by X-ray diffraction, revealing its 3D polymeric nature. The polymer is composed by the assembly of [Tpa 2Cu4I4] units, in which Cu4I 4 presents a step-stair structure. The Tpa ligands bridge the Cu 4I4 clusters, adopting also a μ2: κ2:κ1-coordination mode. As observed for the cationic derivatives, the NMR spectra of 5-8 show the equivalence of the three pyrazolyl arms of the ligands in these complexes. The reactivities of cationic copper(I) derivatives 1-4 with PPh3 and CO have been explored. In all cases, 1:1 adducts [TpaxCuL]PF6 [L = PPh3 (9-11), CO (12-15)] have been isolated. The crystal structure of [Tpa*Cu(PPh3)]PF6 (9) has been obtained, showing that the coordination geometry around copper(I) is trigonal-pyramidal with the apical position occupied by the tertiary amine N atom. The Tpa* ligand binds the Cu center to three of its four N atoms, with one pyrazolyl arm remaining uncoordinated. In solution, the carbonyl adducts 13-15 exist as a mixture of two isomers; the four- and five-coordinate species can be distinguished by means of their IR νCO stretching bands. Finally, the catalytic activities of complexes 1-4 have been demonstrated in carbene- and nitrene-transfer reactions.
- Haldon, Estela,Delgado-Rebollo, Manuela,Prieto, Auxiliadora,Alvarez, Eleuterio,Maya, Celia,Nicasio, M. Carmen,Perez, Pedro J.
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supporting information
p. 4192 - 4201
(2014/05/06)
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- Direct amide formation from N-arylglycine ethyl esters and carboxylic acids catalysed by phenylboronic acid
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The phenylboronic acid-catalysed reaction of an N-arylglycine ethyl ester with various carboxylic acids, including N-acyl-N-phenylglycines, directly affords an amide or a dipeptide in 13-73% yields.
- Huang, Wenhua,Sha, Wen-Bin
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p. 460 - 463
(2013/09/12)
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- Transition metal complexes of novel ethyl pyruvate hydrazones as potential antitumor agents: Synthesis and physicochemical properties, DNA interactions and antiproliferative activity
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A new series of ethyl pyruvate hydrazones and their later first row transition metal(II) complexes have been synthesized and characterized by means of elemental analyses, vibrational, electronic, 1H and 13C NMR, electron paramagnetic resonance, and mass spectroscopic techniques along with thermal and magnetic studies. All complexes were found to be monomeric in nature and have octahedral geometry. The prepared compounds were evaluated for antiproliferative activity against the two human cancer cell lines (HeLa and HepG2). The Cu(II) complexes were found to have potential activity against the cell lines used than the ligand and other complexes. In addition, the DNA-binding/cleaving capacity of the compounds were analyzed by absorption spectroscopy, viscosity measurement, thermal denaturation studies and gel electrophoresis methods.
- Pathan, Aishakhanam H.,Gudasi, Kalagouda B.
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p. 1504 - 1516
(2013/05/08)
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- Design, synthesis, structural characterization by IR, 1H, 13C, 15N, 2D-NMR, X-ray diffraction and evaluation of a new class of phenylaminoacetic acid benzylidene hydrazines as pfenr Inhibitors
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Recent studies have revealed that plasmodial enoyl-ACP reductase (pfENR, FabI), one of the crucial enzymes in the plasmodial type II fatty acid synthesis II (FAS II) pathway, is a promising target for liver stage malaria infections. Hence, pfENR inhibitors have the potential to be used as causal malarial prophylactic agents. In this study, we report the design, synthesis, structural characterization and evaluation of a new class of pfENR inhibitors. The search for inhibitors began with a virtual screen of the iResearch database by molecular docking. Hits obtained from the virtual screen were ranked according to their Glide score. One hit was selected as a lead and modified to improve its binding to pfENR; from this, a series of phenylamino acetic acid benzylidene hydrazides were designed and synthesized. These molecules were thoroughly characterized by IR, 1H, 13C, 15N, 2D-NMR (COSY, NOESY, 1H-13C, 1H-15N HSQC and HMBC), and X-ray diffraction. NMR studies revealed the existence of conformational/configurational isomers around the amide and imine functionalities. The major species in DMSO solution is the E, E form, which is in dynamic equilibrium with the Z, E isomer. In the solid state, the molecule has a completely extended conformation and forms helical structures that are stabilized by strong hydrogen bond interactions, forming a helical structure stabilized by N-H...O interactions, a feature unique to this class of compounds. Furthermore, detailed investigation of the NMR spectra indicated the presence of a minor impurity in most compounds. The structure of this impurity was deduced as an imidazoline-4-one derivative based on 1H-13C and 1H-15H HMBC spectra and was confirmed from the NOESY spectra. The molecules were screened for in vitro activity against recombinant pfENR enzyme by a spectrophotometric assay. Four molecules, viz. 17, 7, 10, and 12 were found to be active at 7, 8, 10, and 12?μm concentration, respectively, showing promising pfENR inhibitory potential. A classification model was derived based on a binary QSAR approach termed recursive partitioning (RP) to highlight structural characteristics that could be tuned to improve activity.
- Samal, Ramanuj P.,Khedkar, Vijay M.,Pissurlenkar, Raghuvir R. S.,Bwalya, Angela Gono,Tasdemir, Deniz,Joshi, Ramesh A.,Rajamohanan,Puranik, Vedavati G.,Coutinho, Evans C.
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p. 715 - 729
(2013/07/05)
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