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agents halogénés

Cristina Müller, Renáta Farkas, Francesca Borgna, Raffaella M Schmid, Martina Benešová, Roger Schibli
The development of (radio)pharmaceuticals with favorable pharmacokinetic profiles is crucial for allowing the optimization of the imaging or therapeutic potential and the minimization of undesired side effects. The aim of this study was, therefore, to evaluate and compare three different plasma protein binders (PPB-01, PPB-02, and PPB-03) that are potentially useful in combination with (radio)pharmaceuticals to enhance their half-life in the blood. The entities were functionalized with a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator via a l-lysine and β-alanine linker moiety using solid-phase peptide chemistry and labeled with (177)Lu (T1/2 = 6...
September 12, 2017: Bioconjugate Chemistry
Jianhua Zou, Zhihui Yin, Kaikai Ding, Qianyun Tang, Jiewei Li, Weili Si, Jinjun Shao, Qi Zhang, Wei Huang, Xiaochen Dong
Heavy atom effect and configuration are important for BODIPY derivatives to generate singlet oxygen ((1)O2) for photodynamic therapy. Herein, a series of BODIPY derivatives with different halogens were synthesized. (1)O2 quantum yields (QYs) and MTT assay confirm that incorporation of more heavy atoms onto dimeric BODIPY cannot effectively enhance the (1)O2 QYs. Rather, the dark toxicity increases. This phenomenon can be attributed to the competition of heavy atom effect and configuration of dimeric BODIPY...
September 13, 2017: ACS Applied Materials & Interfaces
Dennis Wirth, Kolbein Kolste, Stephen Kanick, David W Roberts, Frédéric Leblond, Keith D Paulsen
Studies have shown that fluorescent agents demarcate tumor from surrounding brain tissue and offer intraoperative guidance during resection. However, visualization of fluorescence signal from tumor below the surgical surface or through the appearance of blood in the surgical field is challenging. We have previously described red light imaging techniques for estimating fluorescent depths in turbid media. In this study, we evaluate these methods over a broader range of fluorophore concentrations, and investigate the ability to resolve multiple fluorescent emissions in the same plane or at different depths along the axis of imaging...
August 1, 2017: Biomedical Optics Express
Amit S Tapkir, Sohan S Chitlange, Ritesh P Bhole
Fragment based Quantitative structure activity relationship (QSAR) analysis on reported 25 2-(2-(4-aryloxybenzylidene) hydrazinyl) benzothiazole dataset as antitubercular agents were carried out. Molecules in the current dataset were fragmented into six fragments (R1, R2, R3, R4, R5, R6).Group based QSAR Models were derived using Multiple linear regression (MLR) analysis and selected on the basis of various statistical parameters. Dataset of benzothiazole reveled importance of presence of halogen atoms on is essential requirement...
October 2017: Data in Brief
Xiaodong Xiong, Fei Tan, Ying-Yeung Yeung
A zwitterionic-salt-catalyzed electrophilic monobromination of arenes with high regioselectivity has been developed. Under mild reaction conditions, a wide range of monobrominated aromatic compounds can be obtained in excellent yields. The reaction can be operated using an extremely low catalyst loading (0.05 mol %) with the inexpensive brominating agent N-bromosuccinimide. The versatility of this catalytic protocol has been demonstrated by the scale-up reaction with a 0.01 mol % catalyst loading to provide the selectively halogenated compound in quantitative yield...
August 7, 2017: Organic Letters
Moritz Balkenhohl, Robert Greiner, Ilya S Makarov, Benjamin Heinz, Konstantin Karaghiosoff, Hendrik Zipse, Paul Knochel
A set of successive regioselective metalations and functionalizations of the 1,5-naphthyridine scaffold are described. A combination of Zn-, Mg-, and Li-TMP (TMP=2,2,6,6-tetramethylpiperidyl) bases and the presence or absence of a Lewis acid (BF3 ⋅OEt2 ) allows the introduction of up to three substituents to the 1,5-naphthyridine core. Also, a novel "halogen dance" reaction was discovered upon metalation of an 8-iodo-2,4-trifunctionalized 1,5-naphthyridine allowing a fourth regioselective functionalization...
August 4, 2017: Chemistry: a European Journal
Barbara Böttcher, Bettina Sarg, Herbert H Lindner, Markus Nagl
Rapid inactivation of antimicrobial test agents after exact incubation times with microorganisms is required in time-kill assays. Sodium thiosulphate and a combination of methionine and histidine were compared for neutralisation of active halogen compounds. Test oxidants were mixed with surplus sodium thiosulphate (3%-6%) or histidine/methionine (1% each) in phosphate-buffered saline and incubated for different times, followed by addition of Staphylococcus aureus, Escherichia coli, or Pseudomonas aeruginosa at 1000CFU/ml...
July 29, 2017: Journal of Microbiological Methods
Shengnan Xiao, Shuai Chen, Yuanyuan Sun, Wuxi Zhou, Huri Piao, Yuqing Zhao
In the current work, 13 novel panaxadiol (PD) derivatives were synthesized by reacting with chloroacetyl chloride and bromoacetyl bromide. Their in vitro antitumor activities were evaluated on three human tumor cell lines (HCT-116, BGC-823, SW-480) and three normal cells (human gastric epithelial cell line-GES-1, hair follicle dermal papilla cell line-HHDPC and rat myocardial cell line-H9C2) by MTT assay. Compared with PD, the results demonstrated that compound 1e, 2d, 2e showed significant anti-tumor activity against three tumor cell lines, the IC50 value of compound 2d against HCT-116 was the lowest (3...
September 1, 2017: Bioorganic & Medicinal Chemistry Letters
Yoshimi Ichimaru, Takeshi Fujii, Hiroaki Saito, Makoto Sano, Taketo Uchiyama, Shinichi Miyairi
Indirubin 3'-oxime (Indox (1b)) suppresses cancer cell growth (IC50: 15μM towards HepG2 cells) and inhibits cell cycle-related kinases such as cyclin-dependent kinases and glycogen synthase kinase-3β. We have previously reported that the conjugation of 1b with oxirane, a protein-reactive component, enhanced the cytotoxic activity of Indox as determined from the IC50 value (1.7μM) of indirubin 3'-(O-oxiran-2-ylmethyl)oxime (Epox/Ind (1c)). Here we prepared Epox/Ind derivatives with one or two halogen atoms or a methoxy group on the aromatic ring(s) of an Indox moiety and studied the structure-activity relationships of the substituent(s)...
July 8, 2017: Bioorganic & Medicinal Chemistry
Steve Scheiner
A series of halide receptors are constructed and the geometries and energetics of their binding to F(-), Cl(-), and Br(-) assessed by quantum calculations. The dicationic receptors are based on a pair of imidazolium units, connected via a benzene spacer. The imidazoliums each donate a proton to a halide in a pair of H-bonds. Replacement of the two bonding protons by Br leads to binding via a pair of halogen bonds. Likewise, chalcogen, pnicogen, and tetrel bonds occur when the protons are replaced, respectively, by Se, As, and Ge...
July 21, 2017: Faraday Discussions
Lucia Carlucci, Angelo Gavezzotti
A theoretical investigation of bond lengths and bond energies for several kinds of halogen bonding interactions is carried out using the PIXEL method. The effect of different kinds of activating agents, fluoro-, nitro-, ethynyl substitution and combinations thereof, is assessed quantitatively, and is found to be fully consistent with the results of literature screenings of the corresponding strengths, as judged by the ease of formation of cocrystals. In the best combination of activators the halogen bond is comparable or superior to a strong O-HO hydrogen bond in what concerns stabilization energies and stretching force constants...
July 5, 2017: Physical Chemistry Chemical Physics: PCCP
Farman Ali, Khalid Mohammed Khan, Uzma Salar, Muhammad Taha, Nor Hadiani Ismail, Abdul Wadood, Muhammad Riaz, Shahnaz Perveen
Acarbose, miglitol, and voglibose are the inhibitors of α-glucosidase enzyme and being clinically used for the management of type-II diabetes mellitus. However, many adverse effects are also associated with them. So, the development of new therapeutic agents is an utmost interest in medicinal chemistry research. Current study is based on the identification of new α-glucosidase inhibitors. For that purpose, hydrazinyl arylthiazole based pyridine derivatives 1-39 were synthesized via two step reaction and fully characterized by spectroscopic techniques EI-MS, HREI-MS, (1)H-, and (13)C NMR...
June 26, 2017: European Journal of Medicinal Chemistry
Frank Keppler, Jan Fischer, Tobias Sattler, Daniela Polag, Nicole Jaeger, Heinz Friedrich Schöler, Markus Greule
Chloromethane (CH3Cl), currently the most abundant chlorinated organic compound in the atmosphere at around ~550 parts per trillion by volume (pptv), is considered responsible for approximately 16% of halogen-catalyzed stratospheric ozone destruction. Although emissions of CH3Cl are known to occur from animals such as cattle, formation and release of CH3Cl from humans has not yet been reported. In this study a pre-concentration unit coupled with a gas chromatograph directly linked to a mass spectrometer was used to precisely measure concentrations of CH3Cl at the pptv level in exhaled breath from 31 human subjects with ages ranging from 3 to 87years...
December 15, 2017: Science of the Total Environment
Bhaskar Das, Sanjukta Patra
Microbial degradation of phenolic pollutants in industrial wastewater is dependent on enzymatic pathway comprising a cascade of phenol metabolizing enzymes. Phenol hydroxylase is the first enzyme of the pathway catalyzing the initial attack on phenol in green algae Chlorella pyrenoidosa. The present work reports cost effective production of partially purified microalgal phenol hydroylase by single step purification and characterization of its kinetic properties with the view of application for enzyme based remediation of phenolic wastewater or in phenolic biosensor...
June 30, 2017: Environmental Technology
Mohamed A B Mostafa, Rosalind M Bowley, Daugirdas T Racys, Martyn C Henry, Andrew Sutherland
A general and regioselective method for the chlorination of activated arenes has been developed. The transformation uses iron(III) triflimide as a powerful Lewis acid for the activation of N-chlorosuccinimide and the subsequent chlorination of a wide range of anisole, aniline, acetanilide, and phenol derivatives. The reaction was utilized for the late-stage mono- and dichlorination of a range of target compounds such as the natural product nitrofungin, the antibacterial agent chloroxylenol, and the herbicide chloroxynil...
July 3, 2017: Journal of Organic Chemistry
Jeffrey A Boerth, Jonathan A Ellman
A Co(III) -catalyzed three-component coupling of C(sp(2) )-H bonds, alkynes, and halogenating agents to give alkenyl halides is reported. This transformation proceeds with high regio- and diastereoselectivity, and is effective for a broad range of aryl and alkyl terminal alkynes. Diverse C-H bond partners also exhibit good reactivity for a range of heteroaryl and aryl systems as well as synthetically useful secondary and tertiary amide, urea, and pyrazole directing groups. This multicomponent transformation is also compatible with allenes in place of alkynes to furnish tetrasubstituted alkenyl halides, showcasing the first halo-arylation of allenes...
August 7, 2017: Angewandte Chemie
Ahmet Atilgan, Timur Islamoglu, Ashlee J Howarth, Joseph T Hupp, Omar K Farha
Effective detoxification of chemical warfare agents is a global necessity. As a powerful photosensitizer, a halogenated BODIPY ligand is postsynthetically appended to the Zr6 nodes of the metal-organic framework (MOF), NU-1000, to enhance singlet oxygen generation from the MOF. The BODIPY/MOF material is then used as a heterogeneous photocatalyst to produce singlet oxygen under green LED irradiation. The singlet oxygen selectively detoxifies the sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES), to the less toxic sulfoxide derivative (2-chloroethyl ethyl sulfoxide, CEESO) with a half-life of approximately 2 min...
July 17, 2017: ACS Applied Materials & Interfaces
Christoph Ascheberg, Jonathan Bock, Florenz Buß, Christian Mück-Lichtenfeld, Constantin G Daniliuc, Klaus Bergander, Fabian Dielmann, Ulrich Hennecke
Electrophilic halogenating agents are an important class of reagents in chemical synthesis. Herein, we show that sterically demanding bromiranium ions with weakly coordinating counterions are highly reactive electrophilic brominating agents. Despite their high reactivity these reagents are stable, in one case even under ambient conditions and can be applied in electrophilic halogenations of alkenes as well as heteroatoms.
June 21, 2017: Chemistry: a European Journal
Joanna Giebułtowicz, Monika Rużycka, Piotr Wroczyński, David A Purser, Anna A Stec
Dwelling fires have changed over the years because building contents and the materials used in then have changed. They all contribute to an ever-growing diversity of chemical species found in fires, many of them highly toxic. These arise largely from the changing nature of materials in interior finishes and furniture, with an increasing content of synthetic materials containing higher levels of nitrogen, halogen and phosphorus additives. While there is still a belief that carbon monoxide is the major lethal toxic agent in fires, the hydrogen cyanide and acid gases released from these additives are now well-recognised as major contributory causes of incapacitation, morbidity and mortality in domestic fires...
June 9, 2017: Forensic Science International
Philipp Schäfer, Thomas Palacin, Mireia Sidera, Stephen P Fletcher
Using asymmetric catalysis to simultaneously form carbon-carbon bonds and generate single isomer products is strategically important. Suzuki-Miyaura cross-coupling is widely used in the academic and industrial sectors to synthesize drugs, agrochemicals and biologically active and advanced materials. However, widely applicable enantioselective Suzuki-Miyaura variations to provide 3D molecules remain elusive. Here we report a rhodium-catalysed asymmetric Suzuki-Miyaura reaction with important partners including aryls, vinyls, heteroaromatics and heterocycles...
June 13, 2017: Nature Communications
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