930-88-1Relevant academic research and scientific papers
Oxidative Cleavage of Indoles Mediated by Urea Hydrogen Peroxide or H2O2 in Polar Solvents
Llopis, Natalia,Gisbert, Patricia,Baeza, Alejandro
supporting information, p. 3245 - 3249 (2021/06/08)
The oxidative cleavage of indoles (Witkop oxidation) involving the use of H2O2 or urea hydrogen peroxide in combination with a polar solvent has been described. Among these solvents, 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) stands out as the one affording the corresponding 2-ketoacetanilides generally in higher yields The protocol described has also enabled the oxidation of different pyrroles and furans derivatives. Furthermore, the procedure was implemented in a larger-scale and HFIP was distilled from the reaction mixture and reused (up to 4 cycles) without a significant detriment in the reaction outcome, which remarks its sustainability and applicability. (Figure presented.).
Design, synthesis and biochemical evaluation of novel ethanoanthracenes and related compounds to target burkitt’s lymphoma
Byrne, Andrew J.,Bright, Sandra A.,McKeown, James P.,O’brien, John E.,Twamley, Brendan,Fayne, Darren,Williams, D. Clive,Meegan, Mary J.
, (2020/01/31)
Lymphomas (cancers of the lymphatic system) account for 12% of malignant diseases worldwide. Burkitt’s lymphoma (BL) is a rare form of non-Hodgkin’s lymphoma in which the cancer starts in the immune B-cells. We report the synthesis and preliminary studies on the antiproliferative activity of a library of 9,10-dihydro-9,10-ethanoanthracene based compounds structurally related to the antidepressant drug maprotiline against BL cell lines MUTU-1 and DG- 75. Structural modifications were achieved by Diels-Alder reaction of the core 9-(2- nitrovinyl)anthracene with number of dienophiles including maleic anhydride, maleimides, acrylonitrile and benzyne. The antiproliferative activity of these compounds was evaluated in BL cell lines EBV? MUTU-1 and EBV+ DG-75 (chemoresistant). The most potent compounds 13j, 15, 16a, 16b, 16c, 16d and 19a displayed IC50 values in the range 0.17–0.38 μM against the BL cell line EBV? MUTU-1 and IC50 values in the range 0.45–0.78 μM against the chemoresistant BL cell line EBV+ DG- 75. Compounds 15, 16b and 16c demonstrated potent ROS dependent apoptotic effects on the BL cell lines which were superior to the control drug taxol and showed minimal cytotoxicity to peripheral blood mononuclear cells (PBMCs). The results suggest that this class of compounds merits further investigation as antiproliferative agents for BL.
The discovery, design and synthesis of potent agonists of adenylyl cyclase type 2 by virtual screening combining biological evaluation
Li, Shanshan,Song, Gao,Wang, Liang-Liang,Weng, Zhiying,Xu, Guowei,Yang, Weimin,Yang, Yanming,Yang, Yaqing,Zhang, Jiajun,Zuo, Zhili
supporting information, (2020/02/27)
Adenylate cyclases (ACs), play a critical role in the conversion of adenosine triphosphate (ATP) into the second messenger cyclic adenosine monophosphate (cAMP). Studies have indicated that adenylyl cyclase type 2 (AC2) is potential drug target for many diseases, however, up to now, there is no AC2-selective agonist reported. In this research, docking-based virtual screening with the combination of cell-based biological assays have been performed for discovering novel potent and selective AC2 agonists. Virtual screening disclosed a novel hit compound 8 as an AC2 agonist with EC50 value of 8.10 μM on recombinant human hAC2 + HEK293 cells. The SAR (structure activity relationship) based on the derivatives of compound 8 was further explored on recombinant AC2 cells and compound 73 was found to be the most active agonist with the EC50 of 90 nM, which is 160-fold more potent than the reported agonist Forskolin and could selectively activate AC2 to inhibit the expression of Interleukin-6. The discovery of a new class of AC2-selective agonists would provide a novel chemical probe to study the physiological function of AC2.
Regioselective hydroarylation and arylation of maleimides with indazoles: Via a Rh(iii)-catalyzed C-H activation
Ghosh, Asim Kumar,Samanta, Sadhanendu,Ghosh, Payel,Neogi, Sukanya,Hajra, Alakananda
supporting information, p. 3093 - 3097 (2020/05/08)
Switchable Rh(iii)-catalyzed highly regioselective hydroarylation and oxidative arylation of maleimides with 2-arylindazoles via C-H activation have been demonstrated. The reaction affords 3-(2-(2H-indazol-2-yl)phenyl)succinimide and 3-(2-(2H-indazol-2-yl)phenyl)maleimide derivatives in high yields with wide functional group tolerance. A mechanistic study was performed to depict C-H bond cleavage that might be involved in the turnover limiting step.
Nickel(II) Tetraphenylporphyrin as an Efficient Photocatalyst Featuring Visible Light Promoted Dual Redox Activities
Mandal, Tanumoy,Das, Sanju,De Sarkar, Suman
supporting information, p. 3200 - 3209 (2019/05/16)
Nickel(II) tetraphenylporphyrin (NiTPP) is presented as a robust, cost-effective and efficient visible light induced photoredox catalyst. The ground state electrochemical data (CV) and electronic absorption (UV-Vis) spectra reveal the excited state redox potentials for [NiTPP]*/[NiTPP].? and NiTPP].+/[NiTPP]* couples as +1.17 V and ?1.57 V vs SCE respectively. The potential values represent NiTPP as a more potent photocatalyst compare to the well-explored [Ru(bpy)3]2+. The non-precious photocatalyst exhibits excited state redox reactions in dual fashions, i. e., it is capable of undergoing both oxidative as well as reductive quenching pathways. Such versatility of a photocatalyst based on first-row transition metals is very scarce. This unique phenomenon allows one to perform diverse types of redox reactions by employing a single catalyst. Two different sets of chemical reactions have been performed to represent the synthetic utility. The catalyst showed superior efficiency in both carbon-carbon and carbon-heteroatom bond-forming reactions. Thus, we believe that NiTPP is a valuable addition to the photocatalyst library and this study will lead to more practical synthetic applications of earth-abundant-metal-based photoredox catalysts. (Figure presented.).
Cp?Co(III)-Catalyzed C-H Alkylation with Maleimides Using Weakly Coordinating Carbonyl Directing Groups
Mandal, Rajib,Emayavaramban, Balakumar,Sundararaju, Basker
supporting information, p. 2835 - 2838 (2018/05/29)
A novel protocol for ortho-C-H alkylation of aromatic and heteroaromatic ketones and esters under Cp?Co(III) catalysis has been developed for the first time. The reaction proceeds through initial cyclometalation via weak chelation-assisted C-H bond activation, followed by coordination of activated alkene, insertion between Co-C, and protodemetalation.
Healing by the Joule effect of electrically conductive poly(ester-urethane)/carbon nanotube nanocomposites
Willocq,Bose,Khelifa,Garcia,Dubois,Raquez
, p. 4089 - 4097 (2016/03/19)
Recent demands for polymers with autonomous self-healing properties are being constantly raised due to the need for high-performance and reliable materials. So far, the advances in this field are limited to the production of self-healing materials requiring a high energy input. Therefore there is an urgent need to develop self-healing polymer systems, in which healing can be easily and specifically induced by external stimuli for economical and viable applications. In the current work we demonstrate, for the first time to our knowledge, the possibility to heal local macroscopic damage by a confined temperature increase arising from the Joule effect. The damage healing is promoted by the resistance to an electrical current at the crack tip. This new concept is studied on thermo-reversible and electrically conductive poly(ester-urethane)/carbon nanotube nanocomposites derived from thermo-reversible Diels-Alder reactions between furfuryl- and maleimide-functionalized poly(ε-caprolactone) (PCL)-based precursors. Electrically conductive materials are then obtained after incorporating multi-walled carbon nanotubes into the thermo-reversible networks using reactive extrusion. Under mild electrical conditions, temperature in the range of the retro-Diels-Alder reaction can be obtained near the damaged site. The obtained results reveal the potential of this new approach for healing materials locally while maintaining the overall material properties.
9,10-Dibromo-N-aryl-9,10-dihydro-9,10-[3,4]epipyrroloanthracene-12,14-diones: Synthesis and Investigation of Their Effects on Carbonic Anhydrase Isozymes I, II, IX, and XII
G?ksu, Haydar,Topal, Meryem,Keskin, Ali,Gültekin, Mehmet S.,?elik, Murat,Gül?in, Ilhami,Tanc, Muhammet,Supuran, Claudiu T.
, p. 466 - 474 (2016/06/09)
N-substituted maleimides were synthesized from maleic anhydride and primary amines. 1,4-Dibromo-dibenzo[e,h]bicyclo-[2,2,2]octane-2,3-dicarboximide derivatives (4a-f) were prepared by the [4+2] cycloaddition reaction of dibromoanthracenes with the N-substituted maleimide derivatives. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the new derivatives were assayed against the human (h) isozymes hCA I, II, IX, and XII. All tested bicyclo dicarboximide derivatives exhibited excellent inhibitory effects in the nanomolar range, with Ki values in the range of 117.73-232.87 nM against hCA I and of 69.74-111.51 nM against hCA II, whereas they were low micromolar inhibitors against hCA IX and XII. A series of 9,10-dibromo-N-aryl-9,10-dihydro-9,10-[3,4]epipyrroloanthracene-12,14-diones (4a-f) were synthesized from N-substituted maleimide derivatives and 9,10-dibromoanthracene. Compounds 4a-f were assayed against human carbonic anhydrases (hCA) IX and XII, which are the two tumor-associated isozymes, and hCA I and II, which represent the most common off-targets for the development of selective anticancer CA inhibitors.
Photoorganocatalysed and visible light photoredox catalysed trifluoromethylation of olefins and (hetero)aromatics in batch and continuous flow
Lefebvre, Quentin,Hoffmann, Norbert,Rueping, Magnus
supporting information, p. 2493 - 2496 (2016/02/18)
Trifluoromethylation of olefins and (hetero)aromatics with sodium triflinate as CF3 source and readily accessible benzophenone derivatives as photosensitisers has been developed in batch and flow. The use of an iridium-based photocatalyst enables the trifluoromethylation to proceed under visible light irradiation.
Study of the diels-alder and retro-diels-alder reaction between furan derivatives and maleimide for the creation of new materials
Froidevaux,Borne,Laborbe,Auvergne,Gandini,Boutevin
, p. 37742 - 37754 (2015/05/13)
The Diels-Alder reaction leads to a mixture of two diastereomers, one called endo and the other one exo. The cyclo-reversion temperature of the first one is lower than the exo adduct and the ratio between endo and exo adducts varies according to the substituents of the Diels-Alder partners and experimental parameters. Therefore, the influence of some reaction parameters such as the substituents of furan and maleimide derivatives, the reaction temperature and the presence of a nucleophile on the endo/exo Diels-Alder ratio and/or the retro-Diels-Alder reaction have been studied. For instance, furan and maleimide derivatives with electron withdrawing substituents induced the creation of the endo adduct preferentially. Also the presence of a far electron withdrawing substituent on furan and/or an electron attracting mesomeric substituent on maleimide resulted in a faster reversibility of the endo adduct. Finally, a high temperature and the presence of a nucleophile (thiol) also induced faster retro-Diels-Alder kinetics. Moreover, it was proved that isomerization from the endo to the exo diastereomer is preceded by a retro-Diels-Alder reaction of the endo adduct. The presence of a nucleophile in the mixture confirmed this result. This study allowed the highlighting of different parameters of the Diels-Alder reaction to obtain as much endo adduct as possible, and a fast and/or full retro-Diels-Alder reaction of this adduct.
