496-72-0Relevant articles and documents
Differential antiproliferative activity of new benzimidazole-4,7-diones
Garuti, Laura,Roberti, Marinella,Pizzirani, Daniela,Pession, Annalisa,Leoncini, Emanuela,Cenci, Valentina,Hrelia, Silvana
, p. 663 - 668 (2004)
Ten benzimidazole-4,7-diones were synthesized and tested in vitro on two tumor cell lines. Several compounds showed a significant antiproliferative activity on K562 cells, although to a different extent, whereas compound 1i showed a highly significant activity on SW620 cells, comparable to that of doxorubicin. Both the substituents in the quinone ring and the position of the nitrogen atom in the pyridine moiety play a crucial role for the biological activity.
Photocatalytic Oxidative [2+2] Cycloelimination Reactions with Flavinium Salts: Mechanistic Study and Influence of the Catalyst Structure
Hartman, Tomá?,Reisnerová, Martina,Chudoba, Josef,Svobodová, Eva,Archipowa, Nataliya,Kutta, Roger Jan,Cibulka, Radek
, p. 373 - 386 (2021/02/01)
Flavinium salts are frequently used in organocatalysis but their application in photoredox catalysis has not been systematically investigated to date. We synthesized a series of 5-ethyl-1,3-dimethylalloxazinium salts with different substituents in the positions 7 and 8 and investigated their application in light-dependent oxidative cycloelimination of cyclobutanes. Detailed mechanistic investigations with a coumarin dimer as a model substrate reveal that the reaction preferentially occurs via the triplet-born radical pair after electron transfer from the substrate to the triplet state of an alloxazinium salt. The very photostable 7,8-dimethoxy derivative is a superior catalyst with a sufficiently high oxidation power (E=2.26 V) allowing the conversion of various cyclobutanes (with Eox up to 2.05 V) in high yields. Even compounds such as all-trans dimethyl 3,4-bis(4-methoxyphenyl)cyclobutane-1,2-dicarboxylate can be converted, whose opening requires a high activation energy due to a missing pre-activation caused by bulky adjacent substituents in cis-position.
Novel cathepsin K inhibitors block osteoclasts in vitro and increase spinal bone density in zebrafish
Xue, Si-Tu,Wang, Ya-Li,Han, Xiao-Wan,Yi, Hong,Jiang, Wei,Si, Shu-Yi,Guo, Hui-Fang,Li, Zhuo-Rong
, p. 8600 - 8607 (2019/03/21)
Cathepsin K (Cat K) is a predominant cysteine protease and highly potent collagenase expressed in osteoclasts. Cat K inhibitors are anti-resorptive agents to treat osteoporosis. A novel scaffold of cathepsin K inhibitors, exemplified by lead compound 1x, was used as the template for designing and synthesizing a total of 61 derivatives that have not been reported before. An exploratory structure-activity relationship analysis identified the potent Cat K inhibitor A22, which displayed an IC50 value of 0.44 μM against Cat K. A22 was very specific for Cat K and caused a significantly higher in vitro inhibition of the enzyme as compared to that of lead compound 1x. A surface plasmon resonance analysis confirmed in vitro binding of A22 to Cat K. Molecular docking studies indicated several favourable interaction sites for A22 within the active pocket of Cat K. Furthermore, A22 also blocked active osteoclasts in vitro and increased spinal bone density in zebrafish, in which it showed an activity that was higher than that of the marketed therapeutic bone metabolizer etidronate disodium. A22 represents a very promising lead compound for the development of novel antiresorptive agents functioning as orthosteric inhibitors of Cat K.
Pd-Pt/modified GO as an efficient and selective heterogeneous catalyst for the reduction of nitroaromatic compounds to amino aromatic compounds by the hydrogen source
Salahshournia, Hossein,Ghiaci, Mehran
, (2019/02/14)
In this work, different nitroaromatic compounds were successfully reduced to their corresponding aromatic amines with excellent conversion and selectivity in methanol at 50?°C by using Pd-Pt nanoparticles immobilized on the modified grapheme oxide (m-GO) and hydrogen as the reducing source. The catalytic efficiency of Pd and Pd-Pt loading on the modified GO was investigated for the reduction of various nitroaromatic compounds, and the Pd-Pt/m-GO system demonstrated the highest conversion and selectivity. The catalyst was characterized by different techniques including FT-IR, Raman, UV–Vis, XRD, BET, XPS, FESEM, EDS, and TEM. The metal nanoparticles with the size of less than 10?nm were uniformly distributed on the m-GO. The catalyst could be reused at least five times without losing activity, showing the stability of the catalyst structure. Finally, the efficiency of the prepared catalyst was compared with Pd-Pt/AC, and Pd-Pt/GO catalysts.
Green synthesis and: In situ immobilization of gold nanoparticles and their application for the reduction of p -nitrophenol in continuous-flow mode
Szcs, Rózsa,Balogh-Weiser, Diána,Sánta-Bell, Evelin,Tóth-Szeles, Eszter,Varga, Tamás,Kónya, Zoltán,Poppe, László,Lagzi, István
, p. 9193 - 9197 (2019/03/28)
A green and facile method has been developed for the preparation of in situ immobilized gold nanoparticles (AuNPs) using agarose as a reducing and stabilizing agent. The size of the synthesized AuNPs ranges between 10 and 100 nm, and their average size can be controlled by the concentrations of the agarose and gold salt. The agarose matrix as a mild and green reaction medium can provide a good dispersion environment for forming AuNPs, and the hydrogel can be well homogenized with polyacrylic macroporous microbeads as well, which can adsorb and stabilize the particles leading to the simultaneous synthesis and immobilization of AuNPs avoiding harmful inorganic compounds or organic solvents. The supported gold nanocatalyst was successfully applied as a catalyst in packed bed reactors for efficient NaBH4-mediated reduction of p-nitrophenol in continuous-flow mode.
Metal-free Reduction of Nitro Aromatics to Amines with B 2 (OH) 4 /H 2 O
Chen, Danyi,Zhou, Yanmei,Zhou, Haifeng,Liu, Sensheng,Liu, Qixing,Zhang, Kaili,Uozumi, Yasuhiro
supporting information, p. 1765 - 1768 (2018/06/26)
A metal-free reduction of nitro aromatics mediated by diboronic acid with water as both the hydrogen donor and solvent under mild conditions has been developed. A series of aromatic amines were obtained with good functional group tolerance and in good yields.
A capping agent dissolution method for the synthesis of metal nanosponges and their catalytic activity towards nitroarene reduction under mild conditions
Ghosh, Sourav,Jagirdar, Balaji R.
, p. 17401 - 17411 (2019/01/03)
We report a general strategy for the synthesis of metal nanosponges (M = Ag, Au, Pt, Pd, and Cu) using a capping agent dissolution method where addition of water to the M@BNHx nanocomposite affords the metal nanosponges. The B-H bond of the BNHx polymer gets hydrolysed upon addition of water and produces hydrogen gas bubbles which act as dynamic templates leading to the formation of nanosponges. The rate of B-H bond hydrolysis has a direct impact on the final nanostructure of the materials. The metal nanosponges were characterized using powder XRD, electron microscopy, XPS, and BET surface area analyzer techniques. The porous structure of these nanosponges offers a large number of accessible surface sites for catalytic reactions. The catalytic activity of these metal nanosponges has been demonstrated for the reduction of 4-nitrophenol where palladium exhibits the highest catalytic activity (k = 0.314 min?1). The catalytic activity of palladium nanosponge was verified for the tandem dehydrogenation of ammonia borane and the hydrogenation of nitroarenes to arylamines in methanol at room temperature. The reduction of various substituted nitroarenes was proven to be functional group tolerant except for a few halogenated nitroarenes (X = Br and I) and >99% conversion was noted within 30-60 min with high turnover frequencies (TOF) at low catalyst loading (0.1 mol%). The catalyst could be easily separated out from the reaction mixture via centrifugation and was recyclable over several cycles, retaining its porous structure.
Water as a hydrogen source in palladium-catalyzed reduction and reductive amination of nitroarenes mediated by diboronic acid
Zhou, Yanmei,Zhou, Haifeng,Liu, Sensheng,Pi, Danwei,Shen, Guanshuo
, p. 3898 - 3904 (2017/06/13)
An unprecedented palladium-catalyzed chemoselective reduction and reductive amination of nitroarenes with water as a hydrogen source mediated by diboronic acid have been discovered. A series of aryl amines containing various reducible functional groups were obtained in good to excellent yields.
A containing methyl pyrazine structure of the hydrazone compound and its preparation method and application (by machine translation)
-
Paragraph 0027, (2017/06/02)
The invention discloses a containing methyl pyrazine structure of the hydrazone compound and its preparation method and application. It to 5 - methyl O-nitroaniline and hydrazine hydrate to obtain compound 1; compound 1 with the role of the BMF prepared compound 2; compound 2 by the reaction of the compound with phosphorus oxychloride 3; compound 3 is obtained by the reaction with hydrazine hydrate compound 4; compound 4 with the substituted aldehyde compound by the reaction of the compound (I). Its raw material is simple and easy, simple preparation method, after treatment is convenient, high product yield, but the compound is has herbicidal activity, in particular against bentgrasses, has certain herbicidal effect, to provide the basis for a new pesticide research. (by machine translation)
Potent, Selective, and Cell Active Protein Arginine Methyltransferase 5 (PRMT5) Inhibitor Developed by Structure-Based Virtual Screening and Hit Optimization
Mao, Ruifeng,Shao, Jingwei,Zhu, Kongkai,Zhang, Yuanyuan,Ding, Hong,Zhang, Chenhua,Shi, Zhe,Jiang, Hualiang,Sun, Dequn,Duan, Wenhu,Luo, Cheng
, p. 6289 - 6304 (2017/08/02)
PRMT5 plays important roles in diverse cellular processes and is upregulated in several human malignancies. Besides, PRMT5 has been validated as an anticancer target in mantle cell lymphoma. In this study, we found a potent and selective PRMT5 inhibitor by performing structure-based virtual screening and hit optimization. The identified compound 17 (IC50 = 0.33 μM) exhibited a broad selectivity against a panel of other methyltransferases. The direct binding of 17 to PRMT5 was validated by surface plasmon resonance experiments, with a Kd of 0.987 μM. Kinetic experiments indicated that 17 was a SAM competitive inhibitor other than the substrate. In addition, 17 showed selective antiproliferative effects against MV4-11 cells, and further studies indicated that the mechanism of cellular antitumor activity was due to the inhibition of PRMT5 mediated SmD3 methylation. 17 may represent a promising lead compound to understand more about PRMT5 and potentially assist the development of treatments for leukemia indications.
