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Galina A Gazieva, Alexei N Izmest'ev, Lada V Anikina, Sergey A Pukhov, Marina E Meshchaneva, Dmitry V Khakimov, Natalya G Kolotyrkina, Angelina N Kravchenko
A series of tetrahydroimidazo[4,5-e]thiazolo[3,2-b]-1,2,4-triazine-2,7(1H, 6H)-diones were synthesized via the reaction of imidazotriazinethiones and bromoacetic acid followed by condensation with isatins. Amidine skeletal rearrangement of 3,3a,9,9a-tetrahydroimidazo[4,5-e]thiazolo[3,2-b]-1,2,4-triazine-2,7 (1H, 6H)-diones into 1,3a,4,9a-tetrahydroimidazo[4,5-e]thiazolo[2,3-c]-1,2,4-triazine-2,8 (3H, 7H)-diones under KOH treatment has been studied. The influence of substituents at positions 1,3,3a,6,9a of imidazothiazolotriazine on the ability to undergo rearrangement was analyzed based on experimental data and theoretical calculations...
March 14, 2018: Molecular Diversity
Srinivas Angapelly, P V Sri Ramya, Rohini Sodhi, Andrea Angeli, Krishnan Rangan, Narayana Nagesh, Claudiu T Supuran, Mohammed Arifuddin
A practical and transition metal-free one-pot domino synthesis of diversified (1,3,4-oxadiazol-2-yl)anilines has been developed employing isatins and hydrazides as the starting materials, in the presence of molecular iodine. The prominent feature of this domino process involves consecutive condensation, hydrolytic ring cleavage, and an intramolecular decarboxylation, in a one-pot process that leads to the oxidative formation of a C-O bond. Fluorescence properties of some of the representative molecules obtained in this way were studied...
December 2018: Journal of Enzyme Inhibition and Medicinal Chemistry
Wen-Kui Yuan, Tao Cui, Wei Liu, Li-Rong Wen, Ming Li
A new CuI/1,10-phen-catalyzed reaction for the synthesis of 3-ylideneoxindoles from readily available isatins and ethyl isocyanoacetate, in which ethyl isocyanoacetate acts as a latent two-carbon donor like the Wittig reagent, is reported. A tandem procedure including 1,3-dipolar cycloaddition/inverse 1,3-dipolar ring opening/olefination allows the preparation of 3-ylideneoxindoles with broad functional group tolerance.
March 8, 2018: Organic Letters
Chun Ma, Jia-Yu Zhou, Yi-Zhu Zhang, Guang-Jian Mei, Feng Shi
The first catalytic asymmetric [2+3] cyclization of azlactones with azonaphthalenes has been established. This strategy allowed the synthesis of a variety of chiral isatin derivatives in generally good yields and excellent enantioselectivities (up to 99% yield, 98% ee). The developed reaction not only represents the first catalytic enantioselective [2+3] cyclization using azlactones as two-carbon building blocks but also enriches the chemistry of catalytic asymmetric cyclizations of azonaphthalenes. In addition, this protocol will provide a useful method for constructing enantioenriched 3,3'-disubstituted isatin-type frameworks...
March 7, 2018: Angewandte Chemie
Chandrasekar Balachandran, Jebiti Haribabu, Kumaramangalam Jeyalakshmi, Nattamai S P Bhuvanesh, Ramasamy Karvembu, Nobuhiko Emi, Suresh Awale
Three novel complexes (1, 3 and 4) ligating N-substituted isatin thiosemicarbazone derivatives have been synthesized and their structural and biological characteristics have been compared with those of the known analogs (2, 5-7 and 8). In addition, the structure of the representative ligands (L1, L3 and L4) and complex (4) was confirmed by single crystal X-ray diffraction method. All the complexes (1-8) were assessed for their cytotoxic property against a panel of four human cancer cells such as HepG-2 (liver), MOLM-14 (acute monocytic leukemia), U937 (histiocytic lymphoma)...
February 24, 2018: Journal of Inorganic Biochemistry
Víctor Laina-Martín, Jorge Humbrías-Martín, José A Fernández-Salas, José Alemán
A highly enantioselective organocatalytic vinylogous Mukaiyama aldol reaction of silyloxy dienes and isatins under bifunctional organocatalysis is presented. Substituted 3-hydroxy-2-oxindoles are synthesised in good yields and enantioselectivities. These synthetic intermediates are used for the construction of more complex molecules with biological properties such as the formal synthesis of a CB2 agonist presented.
February 27, 2018: Chemical Communications: Chem Comm
Bence Szilágyi, Péter Kovács, György G Ferenczy, Anita Rácz, Krisztina Németh, Júlia Visy, Pál Szabó, Janez Ilas, György T Balogh, Katalin Monostory, István Vincze, Tamás Tábi, Éva Szökő, György M Keserű
d-Amino acid oxidase (DAAO) is a potential target in the treatment of schizophrenia as its inhibition increases brain d-serine level and thus contributes to NMDA receptor activation. Inhibitors of DAAO were sought testing [6+5] type heterocycles and identified isatin derivatives as micromolar DAAO inhibitors. A pharmacophore and structure-activity relationship analysis of isatins and reported DAAO inhibitors led us to investigate 1H-indazol-3-ol derivatives and nanomolar inhibitors were identified. The series was further characterized by pKa and isothermal titration calorimetry measurements...
February 8, 2018: Bioorganic & Medicinal Chemistry
P V Ershov, Yu V Mezentsev, E O Yablokov, L A Kalushskiy, A V Florinskaya, A V Svirid, A A Gilep, S A Usanov, A E Medvedev, A S Ivanov
Cytochrome P450-dependent monooxygenase systems exist basically in all living organisms, where they perform various important functions. The coordinated functioning of these systems involves many proteins participating in different protein-protein interactions (PPI). Previously, we have found that the endogenous non-peptide bioregulator isatin (indoledione-2,3), synthesized from indole by means of certain cytochromes P450 (e.g. P450 2E1, P450 2C19, P450 2A6) regulates affinity of some PPI. In this work, an attempt has been undertaken to register a direct interaction of isatin with a set of different proteins related to the functioning of cytochrome P450-dependent monooxygenase: five isoforms of cytochromes P450, two isoforms of cytochrome b5, cytochrome P450 reductase, adrenodoxin, adrenodoxin reductase and ferrochelatase...
January 2018: Biomedit︠s︡inskai︠a︡ Khimii︠a︡
Nai-Kai Li, Wei-Tai Fan, Jun-Qi Zhang, Bing-Bing Sun, Jun-Bo Chen, Xing-Wang Wang
A combination of metal- and organo-catalysts sequentially catalyzing the Friedel-Crafts/aldol tandem reaction between 3-pyrrolyl-oxindoles and isatin-derived β,γ-unsaturated α-ketoesters has been reported, which leads to two types of diastereomeric enantio-enriched bispirooxindoles with three quaternary stereocentres and synthetically valuable functional groups in high yields with excellent enantioselectivity and diastereoselectivity.
February 13, 2018: Chemical Communications: Chem Comm
Dominik R Brkić, Aleksandra R Božić, Aleksandar D Marinković, Miloš K Milčić, Nevena Ž Prlainović, Fathi H Assaleh, Ilija N Cvijetić, Jasmina B Nikolić, Saša Ž Drmanić
The ratios of E/Z isomers of sixteen synthesized 1,3-dihydro-3-(substituted phenylimino)-2H-indol-2-one were studied using experimental and theoretical methodology. Linear solvation energy relationships (LSER) rationalized solvent influence of the solvent-solute interactions on the UV-Vis absorption maxima shifts (νmax) of both geometrical isomers using the Kamlet-Taft equation. Linear free energy relationships (LFER) in the form of single substituent parameter equation (SSP) was used to analyze substituent effect on pKa, NMR chemical shifts and νmax values...
February 2, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Gehad Lotfy, El Sayed H El Ashry, Mohamed M Said, El Sayed El Tamany, Yasmine M Abdel Aziz, Abdullah Al-Dhfyan, Abdullah M Al-Majid, Assem Barakat
Owing to their structural novelty and inherent three-dimensionality, spiro scaffolds have been shown indisputable promise as chemopreventive agents. A new series of heterocycles containing spirooxindole and pyrrolidine rings were synthesized by the 1,3-dipolar cycloaddition of an azomethine ylide, which was generated in situ by the condensation of a secondary amino acid (l‑proline) and dicarbonyl compounds (isatin), with dipolarophiles. This method is simple and provides diverse and biologically interesting products...
January 31, 2018: Journal of Photochemistry and Photobiology. B, Biology
Dr Sanjeeva Kumar Arupula, Soumitra Guin, Anubha Yadav, Shaikh M Mobin, Sampak Samanta
An efficient, organocatalytic and eco-friendly method has been developed for the quick construction of a wide array of 3,3-disubstituted oxindoles in good to excellent yields and diastereomeric ratio (up to ≤96:4) with excellent functional group tolerance via an allylic alkylation reaction of cyclic sulfamidate imines with a number of MBH carbonates of isatins in 2-MeTHF as environment benign solvent at room temperature using 5 mol% of DABCO. Furthermore, a metal-free based one-shot synthesis of a medicinally promising polycyclic spirooxindoles with an all carbon spirocenter has been achieved in outstanding dr value (up to ≤99:1)...
February 7, 2018: Journal of Organic Chemistry
Ryan D Brown, Steven A Corcelli, S Alex Kandel
Traditionally, the goal of self-assembly and supramolecular chemistry is to engineer an equilibrium structure with a desired geometry and functionality; this is achieved through careful choice of molecular monomers, growth conditions, and substrate. Supramolecular assemblies produced under nonequilibrium conditions, in contrast, can form metastable structures with conformations quite different from those accessible in equilibrium self-assembly. The study of nonequilibrium growth of clusters potentially impacts the study of nucleation in atmospheric aerosols, nucleation in organic crystallization, and mesoscale organization for systems ranging from biological molecules to molecular electronics...
January 30, 2018: Accounts of Chemical Research
Xiao-Long He, Hui-Ru Zhao, Chuan-Qi Duan, Wei Du, Ying-Chun Chen
A previously unreported activation mode is developed through the generation of dearomatizative tetraenamine species between 5-allylic furfurals and a bifunctional amine-thiourea catalyst. The very remote ζ,η-alkenes perform as effective HOMO-raised dienophiles in inverse-electron-demand oxa-Diels-Alder cycloadditions with isatin-derived oxadiene substrates, delivering multifunctional spirocyclic oxindoles incorporating a dihydropyran skeleton in moderate to high yields with good to excellent enantio- and diastereoselectivity...
January 22, 2018: Organic Letters
A V Svirid, P V Ershov, E O Yablokov, L A Kaluzhskiy, Yu V Mezentsev, A V Florinskaya, T A Sushko, N V Strushkevich, A A Gilep, S A Usanov, A E Medvedev, A S Ivanov
Thromboxane synthase (TBXAS1) catalyzes the isomerization reaction of prostaglandin H2 producing thromboxane A2, the autocrine and paracrine factor in many cell types. A high activity and metastability by these arachidonic acid derivatives suggests the existence of supramolecular structures that are involved in the regulation of the biosynthesis and directed translocation of thromboxane to the receptor. The objective of this study was to identify TBXAS1 protein partners from human liver tissue lysate using a complex approach based on the direct molecular fishing technique, LC-MS/MS protein identification, and protein-protein interaction validation by surface plasmon resonance (SPR)...
October 2017: Acta Naturae
Alexei Medvedev, Olga Buneeva, Oksana Gnedenko, Pavel Ershov, Alexis Ivanov
Isatin (indole-2,3-dione) is an oxidized indole. It is widely distributed in mammalian tissues and body fluids, where isatin concentrations vary significantly from <0.1 to > 10 µM. Isatin output is increased under conditions of stress. Exogenously administered isatin is characterized by low toxicity, mutagenicity, and genotoxicity in vivo. Cytotoxic effects of isatin on various cell cultures are usually observed at concentrations exceeding 100 µM. Binding of [3 H]isatin to rat brain sections is consistent with its physiological concentrations...
January 16, 2018: BioFactors
Bao-Qu Wang, Cong-Hai Zhang, Xiao-Xue Tian, Jun Lin, Sheng-Jiao Yan
A one-step methodology for the synthesis of multisubstituted quinoline-4-carboxamides was developed by simply refluxing a mixture of isatins 1 and various kinds of 1,1-enediamines 2-4 in a reaction catalyzed by NH2SO3H. As a result, a series of quinolone-4-carboxamides were produced through a novel cascade reaction mechanism. This reaction involved the formation of the quinoline ring accompanied by the formation of an amide bond in one step. Accordingly, this protocol is suitable for combinatorial and parallel syntheses of quinolone-4-carboxamide drugs or natural products...
January 11, 2018: Organic Letters
Hamid Reza Safaei, Mohsen Shekouhy
γ-Spiroiminolactone derivatives can be synthesized through an one-pot three-component reaction of cyclic carbonyl compounds (isatin, acenaphthoquinone, ninhydrin), activated α-methylene carbonyl groups and isocyanides in water using sodium dodecyl sulfate (SDS) as a commercially available and cheap surfactant compound. All products were obtained in good to excellent yields without formation of any by-products in water as a green and benign reaction medium. Moreover, presented method was successfully applied for the synthesis of some novel bis(spiroiminolactone) derivatives...
December 2017: Acta Chimica Slovenica
Max Moskowitz, Kaluvu Balaraman, Christian Wolf
A highly diastereoselective organocatalytic method that produces 3-fluoro-3'-hydroxy-3,3'-bisoxindoles and the corresponding 3-fluoro-3'-amino derivatives having two adjacent chirality centers from fluorooxindoles and isatins in high yields is described. The reaction occurs in protic solvents at room temperature, it can be upscaled without compromising yield and stereoselectivity, and chromatographic product purification is not required.
January 9, 2018: Journal of Organic Chemistry
Mahshid Hamzehloueian, Zakieh Davari
The molecular mechanism of the [3+2] cycloaddition (32CA) reaction of an azomethine ylide, generated in situ from isatin and sarcosine, with benzo-imidazol-2-yl-3-phenylacrylonitrile have been theoretically studied by using DFT at the B3LYP and M06-2X levels of theory. This reaction takes place through an asynchronous one-step mechanism. Analysis of the global electron density transfer (GEDT) indicates that this 32CA has a polar character. The regiochemistry of this reaction was investigated using Parr functions analysis, as well as HSAB principle and potential energy surface analysis, where the results are in agreement with the experimental observations...
December 29, 2017: Journal of Molecular Graphics & Modelling
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