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Multicomponent Reaction

Yanira Méndez, German De Armas, Idalia Pérez, Tamara Rojas, Mario E Valdés-Tresanco, Maikel Izquierdo, Maday Alonso Del Rivero, Yoanna María Álvarez-Ginarte, Pedro A Valiente, Carmen Soto, Lena de León, Aldrin V Vasco, William L Scott, Bernhard Westermann, Jorge González-Bacerio, Daniel G Rivera
The Escherichia coli neutral M1-aminopeptidase (ePepN) is a novel target identified for the development of antimicrobials. Here we describe a solid-phase multicomponent approach which enabled the discovery of potent ePepN inhibitors. The on-resin protocol, developed in the frame of the Distributed Drug Discovery (D3) program, comprises the implementation of parallel Ugi-azide four-component reactions with resin-bound amino acids, thus leading to the rapid preparation of a focused library of tetrazole-peptidomimetics (TPMs) suitable for biological screening...
December 1, 2018: European Journal of Medicinal Chemistry
Sung-Eun Suh, Shuming Chen, K N Houk, David M Chenoweth
This article describes an experimental and computational investigation on the possible aryne reactivity modes in the course of the reaction of two highly energetic molecules, an aryne and a 1,2,4,5-tetrazine. Beyond the triple aryne-tetrazine (TAT) reaction, it was observed that combinations of several reactivity modes afford several heterocyclic compounds. Density Functional Theory (DFT) calculations of competition between a second Diels-Alder reaction and the nucleophilic addition pathways indicates the latter to be more favorable...
October 21, 2018: Chemical Science
Nadine Döben, Hong Yan, Marvin Kischkewitz, Jincheng Mao, Armido Studer
Multicomponent reactions of diazo compounds have attracted much attention in recent years. Such transformations are generally conducted by applying transition metal catalysis and involve the corresponding metal carbenes as key intermediates. In this letter, a metal-free three-component intermolecular acetoxyaminoalkylation of α-diazo amides with tertiary aryl amines and (diacetoxyiodo)benzene is presented.
December 12, 2018: Organic Letters
Georgios Giannakakis, Maria Flytzani-Stephanopoulos, E Charles H Sykes
Heterogeneous catalysts are workhorses in the industrial production of most commodity and specialty chemicals, and have widespread energy and environmental applications, with the annual market value of the catalysts themselves reaching almost $20 billion in 2018. These catalysts are complex, comprising multicomponent materials and multiple structures, making their rational design challenging, if not impossible. Furthermore, typical active metals like Pt, Pd, and Rh are expensive and can be susceptible to poisoning by CO, coking, and they are not always 100% selective...
December 12, 2018: Accounts of Chemical Research
Forrest A L Laskowski, Michael R Nellist, Jingjing Qiu, Shannon W Boettcher
Solar-water-splitting provides a mechanism to convert and store solar energy in the form of stable chemical bonds. Water-splitting systems often include semiconductor photoanodes, such as n-Fe2O3 and n-BiVO4, which use photogenerated holes to oxidize water. These photoanodes often exhibit improved performance when coated with metal-oxide/(oxy)hydroxide overlayers that are catalytic for the water oxidation reaction. The mechanism for this improvement, however, remains a controversial topic. This is, in part, due to a lack of experimental techniques that are able to directly track the flow of photogenerated holes in such multicomponent systems...
December 11, 2018: Journal of the American Chemical Society
Domna Iordanidou, Tryfon Zarganes-Tzitzikas, Constantinos G Neochoritis, Alexander Dömling, Ioannis N Lykakis
The catalytic efficacy of silver nanoparticles was investigated toward the chemoselective reduction of nitro-tetrazole or amino acid-substituted derivatives into the corresponding amines in high isolated yields. This highly efficient protocol was thereafter applied toward the multicomponent reaction synthesis of heterocyclic dihydroquinoxalin-2-ones with high isolated yields. The reaction proceeds with low catalyst loading (0.8-1.4 mol %) and under mild catalytic conditions, a very good functional-group tolerance, and high yields and can be easily scaled up to more than 1 mmol of product...
November 30, 2018: ACS Omega
Jitender Bariwal, Rupinder Kaur, Leonid G Voskressensky, Erik V Van der Eycken
Multicomponent reactions (MCRs) have proved as a valuable tool for organic and medicinal chemist because of their ability to introduce a large degree of chemical diversity in the product in a single step and with high atom economy. One of the dominant MCRs is the Ugi reaction, which involves the condensation of an aldehyde (or ketone), an amine, an isonitrile, and a carboxylic acid to afford an α-acylamino carboxamide adduct. The desired Ugi-adducts may be constructed by careful selection of the building blocks, opening the door for desired post-Ugi modifications...
2018: Frontiers in Chemistry
Surjendu Maity, Joydip Chaudhuri, Shirsendu Mitra, Saptak Rarotra, Dipankar Bandyopadhyay
We explore the improvements in yield and conversion of a chemical reaction inside a two-phase microfluidic reactor when subjected to an externally applied alternating current (AC) electric field. A computational fluid dynamic (CFD) framework has been developed to incorporate the descriptions of the two-phase flow, multicomponent transport and reaction, and the Maxwell's stresses generated at oil-water interface owing to the presence of the externally applied electric field. The CFD model ensures that the reactants are flown into a microchannel together with the oil and water phases before the reaction takes place at the interface and products diffuse back to the bulk phases...
December 4, 2018: Electrophoresis
Tanu Kaushal, Gaurava Srivastava, Ashok Sharma, Arvind Singh Negi
Quinoxalines are benzopyrazines containing benzene and pyrazine rings fused together. In the recent past, quinoxalines have attracted Medicinal Chemists considerably for their syntheses and chemistry due to their distinct pharmacological activities. Diverse synthetic protocols have been developed via multicomponent reactions, single pot synthesis and combinatorial approach using efficient catalysts, reagents, and nano-composites etc. Further, the versatility of the quinoxaline core and its reasonable chemical simplicity devise it extremely promising source of bioactive compounds...
November 15, 2018: Bioorganic & Medicinal Chemistry
Camila S Pires, Daniela H de Oliveira, Maria R B Pontel, Jean C Kazmierczak, Roberta Cargnelutti, Diego Alves, Raquel G Jacob, Ricardo F Schumacher
A one-pot iodine-catalyzed multicomponent reaction has been developed for the selective preparation of 5-amino-4-(arylselanyl)-1 H -pyrazoles from a diverse array of benzoylacetonitriles, arylhydrazines and diaryl diselenides. The reactions were conducted in MeCN as solvent at reflux temperature under air. The methodology presents a large functional group tolerance to electron-deficient, electron-rich, and bulky substituents and gave the expected products in good to excellent yields. The synthesized 1,3-diphenyl-4-(phenylselanyl)-1 H -pyrazol-5-amine was submitted to an oxidative dehydrogenative coupling to produce a diazo compound confirmed by X-ray analysis...
2018: Beilstein Journal of Organic Chemistry
Gabriele A Berwaldt, Daniela P Gouvêa, Daniel S da Silva, Adriana M das Neves, Mayara S P Soares, Juliana H Azambuja, Geonir M Siqueira, Roselia M Spanevello, Wilson Cunico
A series of nineteen benzothiazin-4-ones from N-(3-aminopropyl) piperidine, 4-(2-aminoethyl)morpholine or 1-(2-aminoethyl)piperidine, aliphatic or aromatic aldehyde and thiosalicylic acid, were synthesized in good yields by multicomponent one-pot reactions. The solvent was toluene and this efficient procedure afforded the desired heterocycles in 5 h. Identification and characterization were achieved by NMR and GC-MS techniques. In vitro AChE activities of all compounds were evaluated in cerebral cortex and hippocampus of rats and in general, the results in cortex were more promising than hippocampus...
December 2019: Journal of Enzyme Inhibition and Medicinal Chemistry
Youliang Zhao
Multicomponent miktoarm stars (MMSs) comprising at least three kinds of chemically different arm segments are extremely important due to their great potential as multiphase materials to elucidate composition/topology-dependent properties and applications. At present, a "core first" route gives ABC stars, "coupling onto" and combinatorial methods afford ABC and ABCD stars, and modular and iterative approaches enable facile synthesis of MMSs with five or more components. Meanwhile, the introduction of stimuli-labile linkages and couplable groups into star polymers further enriches the family of smart materials...
November 27, 2018: Macromolecular Rapid Communications
Makoto Ohsawa, Yukiko Tanaka, Yoshito Ehara, Setsuko Makita, Kosuke Onaka
A recent classification analysis of neuropsychiatric symptoms in patients with Alzheimer's disease (AD) revealed a distinct cluster with apathy and eating problems including anorexia that exhibits frailty. The apathy and frailty are risk factors in the disease progresses. However, there is currently no effective drug for treating both anorexia and apathy in AD. Here, we conducted an open-label pilot study to determine whether ninjin'yoeito (NYT, TJ-108), a multicomponent drug, is effective for improving anorexia and apathy in patients with AD, and consequently their cognitive function...
December 9, 2017: JAD Reports
Katrina Brudzynski, Liset Maldonado-Alvarez
Honey is composed of macromolecules arranged into multicomponent colloidal particles dispersed in a supersaturated sugar solution. The core part of colloidal particles in honey is made up of high-molecular weight protein-polyphenol complexes. We designed a multi-step extraction process to gain better insight into the phenolic compounds strongly bound to proteins in honey. Honeys were sequentially extracted by solvents of reduced polarities and the extraction process was monitored by LC-ESI-MS/MS. Unexpectedly, the results revealed ubiquinone-like compounds that partitioned to both, soluble supernatants and protein-bound insoluble residues from which they were released after the pronase-digestion of proteins...
November 23, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ettore Fazio, Kim A Winterfeld, Ana López-Pérez, Tomás Torres, Dirk M Guldi, Gema de la Torre
We report herein on the design, the synthesis, and the characterization of a panchromatic, charge stabilizing electron donor-acceptor conjugate: (BBPA)3-ZnPor-ZnPc-SubPc 1. Each component, that is, bis(biphenyl)phenylamine (BBPA), Zn(ii) porphyrin (ZnPor), Zn(ii) phthalocyanine ZnPc, and subphthalocyanine (SubPc), has been carefully chosen and modified to enable a cascade of energy and charge transfer processes. On one hand, ZnPor, has been functionalized with three electron-donating BBPA as primary and secondary electron donors and to stabilize the final charge-separated state, and, on the other hand, a perfluorinated SubPc has been selected as ultimate electron acceptor...
November 26, 2018: Nanoscale
Ouldouz Ghashghaei, Carme Masdeu, Concepción Alonso, Francisco Palacios, Rodolfo Lavilla
The Povarov multicomponent reaction consists on the condensation of an aniline, an aldehyde, and an activated olefin to generate a tetrahydroquinoline adduct with 3 diversity points. Hereby, we report the main features of this transformation and its uses in medicinal chemistry. Relevant examples of the impact of Povarov adducts in different therapeutic areas are provided.
November 2018: Drug Discovery Today. Technologies
Upendra K Sharma, Guilong Tian, Leonid G Voskressensky, Erik V Van der Eycken
Post multicomponent reaction (MCR) transformations are one of the most successful methods leading to high structural diversity and molecular complexity. A well-known MCR, the Ugi reaction typically affords a linear peptide backbone, enabling post-Ugi transformations as an elegant solution to rigidify the Ugi adduct into more drug-like species. Not surprisingly, the development of such transformations leading to new structural frameworks has expanded rapidly over the last few years. These reactions have reached an impressive level of performance and versatility, particularly in amalgamation with gold catalysis...
November 2018: Drug Discovery Today. Technologies
Joanne Tan, Andrei K Yudin
Over the past two decades, there has been an increasing interest in the therapeutic potential of organoboron reagents due to the discovery of bortezomib (Velcade). This has motivated synthetic chemists to develop novel routes for the preparation of heteroatom-rich boron-containing molecules (BCMs). In particular, the development of borylated building blocks has provided facile access to difficult-to-access heteroatom-rich BCMs. In this review, we will discuss the methods used to prepare boron-containing molecules of biological relevance from multicomponent reactions with borylated building blocks...
November 2018: Drug Discovery Today. Technologies
Bo Huang, Sunliang Cui
Being important biological and pharmacological units, β-amino amides and β-acyloxy amides have a privileged position in both academia and industry. Developing a methods to prepare them has gained attention. Ynamides, which possess dual nucleophilic and electrophilic properties, are similar to isonitriles. In this review, usage of ynamides in the single reactant replacement approach of Ugi and Passerini reactions to develop two new multicomponent reactions to get various β-amino amides and β-acyloxy amides is reported...
November 2018: Drug Discovery Today. Technologies
Marta Serafini, Tracey Pirali
Despite benzyne has been known since 1940, this fascinating species has received much attention only over the last decades. The renaissance of interest in aryne chemistry is ascribable to the seminal discovery that arynes can be generated in situ from stable and commercially available precursors under mild and neutral conditions. Thanks to their high reactivity, arynes are key intermediates in countless chemical transformations ranging from cycloadditions to insertions and, among all these approaches, multicomponent reactions (MCRs) are currently standing out in this field...
November 2018: Drug Discovery Today. Technologies
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