121-98-2Relevant articles and documents
Evaluation of nanostructured vanadium(v) oxide in catalytic oxidations
Drew, Eric T.,Yang, Yang,Russo, Julia A.,Campbell, McKenzie L.,Rackley, Samuel A.,Hudson, Joan,Schmuki, Patrik,Whitehead, Daniel C.
, p. 2610 - 2613 (2013)
Nanostructured V2O5 was prepared by electrochemical anodization in the presence of complex fluoride electrolytes. The reactivity of nanostructured V2O5 was compared to a commercially available V2O5 sample in several oxidation reactions. Catalyst nanostructuring offers improvements in yields as well as rate enhancement in oxidations.
Alkoxycarbonylation reactions using aryl fluorosulfonates
Roth, Gregory P.,Thomas, Jeanine A.
, p. 1959 - 1962 (1992)
Aryl fluorosulfonates are shown to undergo palladium catalysed alkoxycarbonylation with a variety of alcohols under mild basic conditions at ambient CO pressure.
Synthesis, biological evaluation of benzothiazole derivatives bearing a 1,3,4-oxadiazole moiety as potential anti-oxidant and anti-inflammatory agents
Bai, Xue-Qian,Cui, Ming-Yue,Li, Chun-Shi,Liang, Cheng-Wu,Song, Ze-Wen,Wang, Hui-Yan,Zhang, Tian-Yi,Zheng, Xian-Jing
, (2020)
Twenty benzothiazole derivatives bearing a 1,3,4-oxadiazole moiety were synthesized and evaluated for their anti-oxidant and anti-inflammatory activities. Among these compounds, 8h and 8l were appeared to have high radical scavenging efficacies as 0.05 ± 0.02 and 0.07 ± 0.03 mmol/L of IC50 values in ABTS+[rad] bioassay, respectively. In anti-inflammatory tests, compound 8h displayed good activity with 57.35% inhibition after intraperitoneal administration, which was more potent than the reference drug (indomethacin). Molecular modeling studies were performed to investigate the binding mode of the representative compound 8h into COX-2 enzyme. In vitro enzyme study implied that compound 8h exerted its anti-inflammatory activity through COX-2 inhibition.
Kito et al.
, p. 3490 (1972)
Total synthesis of aristogin C in aqueous systems
Gao, Hong-Yun,Ha, Cheng-Yong
, p. 3283 - 3286 (2006)
Aristogin C (4), a new diaryl either isolated from the leaves of Aristolochia elegans, was synthesized through a three-step procedure with readily available materials. All of the three reactions were carried out in aqueous systems. Copyright Taylor & Francis Group, LLC.
Photoelectrochemistry on TiO2/Ti anodes as a tool to increase the knowledge about some photo-oxidation mechanisms in CH3CN
Bettoni, Marta,Rol, Cesare,Sebastiani, Giovanni V.
, p. 219 - 224 (2008)
Through current efficiency measurements, obtained from the photoelectrochemical oxidation at TiO2 (rutile)/Ti anodes, further mechanistic information has been obtained regarding the TiO2 photosensitized oxidation of benzylic alcohols, ethers and 1,2-diols in CH 3CN. In deaerated medium, two electrons are captured by the semiconductor from all the considered substrates (one from the substrate, the second from the intermediate benzylic radical). In contrast, in aerated CH 3CN, the number of TiO2-captured electrons can be reduced to one because, depending on its oxidizability, the benzylic radical can be competitively captured by oxygen. Copyright
Electrochemical methoxylation of anethole on a graphite anode
Osadchenko,Tomilov
, p. 2035 - 2036 (2006)
A procedure is suggested for electrochemical methoxylation of anethole in an electrolyzer with a graphite cathode and potassium p-toluenesulfonate in methanol as supporting electrolyte; a mixture of two products is formed in the process.
Design, synthesis, antimicrobial evaluation and molecular modeling study of 1,2,4-triazole-based 4-thiazolidinones
Ahmed, Sahar,Zayed, Mohamed F.,El-Messery, Shahenda M.,Al-Agamy, Mohamed H.,Abdel-Rahman, Hamdy M.
, (2016)
A series of 3-(2H-1,2,4-triazol-5-yl)-1,3-thiazolidin-4-one derivatives (7c-l) was designed and synthesized. Their structures have been elucidated based on analytical and spectral data. They were evaluated for their antibacterial and antifungal activities. Compound 7h showed the highest activity against all tested strains, except P. vulgaris, with MIC 8 μg/mL and 4 μg/mL against S. aureus and C. albicans, respectively. Furthermore, Compounds 7c, 7h, and 7j demonstrated moderate anti-mycobacterium activity. The binding mode of the synthesized thiazolidinones to bacterial MurB enzyme was also studied. Good interactions between the docked compounds to the MurB active site were observed primarily with Asn83, Arg310, Arg188 and Ser82 amino acid residues.
Palladium-catalyzed cleavage reaction of carbon-carbon triple bond with molecular oxygen promoted by lewis acid
Wang, Azhong,Jiang, Huanfeng
, p. 5030 - 5031 (2008)
A new Lewis acid promoted and palladium-catalyzed cleavage reaction of carbon-carbon triple bond with molecular oxygen was reported, in which alkyne or 1.3-diynes is split into carboxylic ester in various alcohols. Copyright
A tunable precious metal-free system for selective oxidative esterification of biobased 5-(hydroxymethyl)furfural
Kozlov, Kirill S.,Romashov, Leonid V.,Ananikov, Valentine P.
, p. 3464 - 3468 (2019)
Oxidative esterification of biomass-derived 5-(hydroxymethyl) furfural (HMF) and furfural and their derivatives has been performed using a simple MnO2/NaCN system. The developed method allows the selective one-pot transformation of HMF to dimethyl furan-2,5-dicarboxylate (FDME) in 83% isolated yield without the formation of a free acid. Simplification of FDME production provides the missing link for manufacturing sustainable value-added materials from biomass. Addition of water to the oxidative system allows fine-tuning of reaction selectivity to obtain the previously difficult-to-access pure methyl 5-(hydroxylmethyl)furan-2-carboxylate in one step directly from the unprotected HMF without chromatographic separation.
End-to-End Azido-Bridged Lanthanide Chain Complexes (Dy, Er, Gd, and Y) with a Pentadentate Schiff-Base [N3O2] Ligand: Synthesis, Structure, and Magnetism
Bazhenova, Tamara A.,Mironov, Vladimir S.,Yakushev, Ilya A.,Svetogorov, Roman D.,Maximova, Olga V.,Manakin, Yuriy V.,Kornev, Alexey B.,Vasiliev, Alexander N.,Yagubskii, Eduard B.
, p. 563 - 578 (2020)
The syntheses, structure and magnetic properties are reported for five novel 1D polymeric azido-bridged lanthanide complexes with the general formula {[Ln(DAPMBH)(N3)C2H5OH]C2H5OH}n where H2DAPMBH = 2,6-diacetylpyridine bis(4-methoxybenzoylhydrazone) - a new pentadentate pyridine-base [N3O2] ligand and Ln = Dy (1), Y0.930Dy0.070 (2), Er (3), Y0.923Er0.077 (4), and Gd (5). X-ray diffraction analysis of 1-5 show that the central lanthanide atoms are eight-coordinated with the N5O3 donor set originating from the ligand DAPMBH, one coordinated ethanol molecule and two end-to-end type N3- bridges connecting the metal centers into infinite chain. The [LnN5O3] coordination polyhedron can be regarded as a distorted dodecahedron (D2d). AC magnetic measurements revealed that compounds 1-4 show field-induced single-molecule magnet behavior, with estimated energy barriers Ueff ≈ 47-17 K. The experimental study of magnetic properties was complemented by theoretical analysis based on crystal-field calculations. Direct current magnetic susceptibility studies revealed marginally weak intrachain exchange interaction between Ln3+ ions mediated by the end-to-end azide bridging groups (J ≈ -0.015 cm-1 for 5). Comparative analysis of static and dynamic magnetic properties of magnetically concentrated (1, 3) and diluted (2, 4) Dy and Er compounds showed that, despite fascinating 1D azido-bridged chain structure, compounds 1 and 3 are not single-chain magnets; their magnetic behavior is largely due to single-ion magnetic anisotropy of individual Ln3+ ions.
Metal-free carbonylations by photoredox catalysis
Majek, Michal,Von Wangelin, Axel Jacobi
, p. 2270 - 2274 (2015)
The synthesis of benzoates from aryl electrophiles and carbon monoxide is a prime example of a transition-metalcatalyzed carbonylation reaction which is widely applied in research and industrial processes. Such reactions proceed in the presence of Pd or Ni catalysts, suitable ligands, and stoichiometric bases. We have developed an alternative procedure that is free of any metal, ligand, and base. The method involves a redox reaction driven by visible light and catalyzed by eosin Y which affords alkyl benzoates from arene diazonium salts, carbon monoxide, and alcohols under mild conditions. Tertiary esters can also be prepared in high yields. DFT calculations and radical trapping experiments support a catalytic photoredox pathway without the requirement for sacrificial redox partners.
Design and synthesis of novel HDAC8 inhibitory 2,5-disubstituted-1,3,4-oxadiazoles containing glycine and alanine hybrids with anti cancer activity
Pidugu, Vijaya Rao,Yarla, Nagendra Sastry,Pedada, Srinivasa Rao,Kalle, Arunasree M.,Satya, A. Krishna
, p. 5611 - 5617 (2016)
Oxadiazole is a heterocyclic compound containing an oxygen atom and two nitrogen atoms in a five-membered ring. Of the four oxadiazoles known, 1,3,4-oxadiazole has become an important structural motif for the development of new drugs and the compounds containing 1,3,4-oxadiazole cores have a broad spectrum of biological activity. Herein, we describe the design, synthesis and biological evaluation of a series of novel 2,5-disubstituted 1,3,4-oxadiazoles (10a–10j) as class I histone deacetylase (HDAC) inhibitors. The compounds were designed and evaluated for HDAC8 selectivity using in silico docking software (Glide) and the top 10 compounds with high dock score and obeying Lipinski's rule were synthesized organically. Further the biological HDAC inhibitory and selectivity assays and anti-proliferative assays were carried out. In in silico and in vitro studies, all compounds (10a–10j) showed significant HDAC inhibition and exhibited HDAC8 selectivity. Among all tested compounds, 10b showed substantial HDAC8 inhibitory activity and better anticancer activity which is comparable to the positive control, a FDA approved drug, vorinostat (SAHA). Structural activity relation is discussed with various substitutions in the benzene ring connected on 1,3,4-oxadizole and glycine/alanine. The study warranted further investigations to develop HDAC8-selective inhibitory molecule as a drug for neoplastic diseases. Novel 1,3,4-oxadizole substituted with glycine/alanine showed HDAC8 inhibition.
Aerobic oxidative cleavage and esterification of C[dbnd]C bonds catalyzed by iron-based nanocatalyst
An, Yue,Fu, Weiru,Tan, Shangzhi,Wang, Lianyue,Yu, Xiangzhu,Zhao, Zhengjia,Zhu, Lina
, (2022/02/03)
Functionalization of C[dbnd]C bonds by oxidative cleavage plays an important role in organic synthesis. However, the traditional functionalized products are mainly aldehydes, ketones and carboxylic acids, and the substrates are limited to examples of active aromatic olefins with very scarce inactive olefins. Herein we disclose an efficient protocol for the direct formation of esters by oxidative cleavage of C[dbnd]C bonds using heterogeneous iron nanocomposite catalyst supported on nitrogen-doped carbon materials with molecular oxygen and tert-butylhydroperoxide (TBHP) as the oxidants. The results show that molecular oxygen as the terminal oxidant is mainly responsible for the cleavage process, and that the auxiliary oxidant TBHP promotes the formation of the intermediate epoxide, thus increasing the selectivity of the product. The catalytic system has a wide range of substrate compatibility involving the challenging inactive aliphatic and long-chain alkyl aryl olefins. The catalyst was reused seven times with no loss in catalytic activity. Characterization and control experiments uncover that the core-shell Fe and Fe3C nanoparticles encapsulated by graphitic carbon play a predominant role in catalyzing the oxidative cleavage of olefins to esters. Preliminary mechanistic studies disclose that this process involves both free radical reactions and tandem sequential reactions.
A Mild Heteroatom (O -, N -, and S -) Methylation Protocol Using Trimethyl Phosphate (TMP)-Ca(OH) 2Combination
Tang, Yu,Yu, Biao
, (2022/03/27)
A mild heteroatom methylation protocol using trimethyl phosphate (TMP)-Ca(OH)2combination has been developed, which proceeds in DMF, or water, or under neat conditions, at 80 °C or at room temperature. A series of O-, N-, and S-nucleophiles, including phenols, sulfonamides, N-heterocycles, such as 9H-carbazole, indole derivatives, and 1,8-naphthalimide, and aryl/alkyl thiols, are suitable substrates for this protocol. The high efficiency, operational simplicity, scalability, cost-efficiency, and environmentally friendly nature of this protocol make it an attractive alternative to the conventional base-promoted heteroatom methylation procedures.
Electro-Oxidative Selective Esterification of Methylarenes and Benzaldehydes
Yu, Congjun,?zkaya, Bünyamin,Patureau, Frederic W.
supporting information, p. 3682 - 3687 (2021/02/01)
A mild and green electro-oxidative protocol to construct aromatic esters from methylarenes and alcohols is herein reported. Importantly, the reaction is free of metals, chemical oxidants, bases, acids, and operates at room temperature. Moreover, the design of the electrolyte was found critical for the oxidation state and structure of the coupling products, a rarely documented effect. This electro-oxidative coupling process also displays exceptional tolerance of many fragile easily oxidized functional groups such as hydroxy, aldehyde, olefin, alkyne, as well as neighboring benzylic positions. The enantiomeric enrichment of some chiral alcohols is moreover preserved during this electro-oxidative coupling reaction, making it overall a promising synthetic tool.