Antioxidant potential of curcumin-related compounds studied by chemiluminescence kinetics, chain-breaking efficiencies, scavenging activity (ORAC) and DFT calculations

• Adriana K. Slavova-Kazakova,
• Silvia E. Angelova,
• Timur L. Veprintsev,
• Petko Denev,
• Davide Fabbri,
• Maria Antonietta Dettori,
• Maria Kratchanova,
• Vladimir V. Naumov,
• Aleksei V. Trofimov,
• Rostislav F. Vasil’ev,
• Giovanna Delogu and
• Vessela D. Kancheva

Beilstein J. Org. Chem. 2015, 11, 1398–1411, doi:10.3762/bjoc.11.151

• the side chain that influences the dihedral angle of biphenyl structure. Model 2: Lipid autoxidation Kinetic curves of the lipid autoxidation at concentrations of 1 mM of the studied compounds and of DL-α-tocopherol (11) are presented in Figure 4 and the main kinetic parameters, characterizing the

• phenolic –OH group, which is responsible for the resonance stabilization of the phenoxyl radicals formed and for the lowest level of side reactions. In case of curcumin, considered also as a dehydrozingerone dimer, the relative antioxidant kinetic parameters observed are almost the same as for the couple

• halves are linked together in the biphenyl molecule, i.e., in ortho-position to the phenol –OH group, a steric factor of the longer side chain exerts a different influence on monomer 4 and its corresponding dimer 8. Small differences in the relative kinetic parameters for the couple dimer 7/monomer 3

New palladium–oxazoline complexes: Synthesis and evaluation of the optical properties and the catalytic power during the oxidation of textile dyes

• Rym Hassani,
• Mahjoub Jabli,
• Yakdhane Kacem,
• Jérôme Marrot,
• Damien Prim and
• Béchir Ben Hassine

Beilstein J. Org. Chem. 2015, 11, 1175–1186, doi:10.3762/bjoc.11.132

• . Thermodynamic parameters To better understand the degradation process, the pseudo first-order kinetic equation was used to determine the kinetic parameters. The Arrhenius law was used to calculate the activation energy (Ea). The determination of the entropy and the enthalpy of activations (ΔS* and ΔH*) were

Release of β-galactosidase from poloxamine/α-cyclodextrin hydrogels

• César A. Estévez,
• José Ramón Isasi,
• Eneko Larrañeta and
• Itziar Vélaz

Beilstein J. Org. Chem. 2014, 10, 3127–3135, doi:10.3762/bjoc.10.330

• 90R4 (25%, t50 = 40–50 min). Also, the amount of enzyme released was higher for mixtures with 25% Tetronic. Using suitable mathematical models, the corresponding kinetic parameters have been calculated. In all cases, the release data fit quite well to the Peppas–Sahlin model equation, indicating that

Tailoring of organic dyes with oxidoreductive compounds to obtain photocyclic radical generator systems exhibiting photocatalytic behavior

• Christian Ley,
• Julien Christmann,
• Ahmad Ibrahim,
• Luciano H. Di Stefano and
• Xavier Allonas

Beilstein J. Org. Chem. 2014, 10, 936–947, doi:10.3762/bjoc.10.92

• reductive pathway, while on the left side the primary reaction occurs with the acceptor A leading to the oxidative pathway. Gibbs free energy of the different electron transfer reactions occurring in a three component PCIS. Thermodynamic and kinetic parameters of the PCIS simulation, kq: quenching rate

Continuous flow nitration in miniaturized devices

• Amol A. Kulkarni

Beilstein J. Org. Chem. 2014, 10, 405–424, doi:10.3762/bjoc.10.38

• limited. The authors showed that the kinetic parameters are a function of the sulfuric acid concentration, which acts as a catalyst. While the adiabatic operation was shown to work in this case, the set of optimal conditions or the effect of various parameters on the yield of the product was not reported

Electron self-exchange activation parameters of diethyl sulfide and tetrahydrothiophene

• Martin Goez and
• Martin Vogtherr

Beilstein J. Org. Chem. 2013, 9, 1448–1454, doi:10.3762/bjoc.9.164

• (wavelength, 308 nm) and the NMR observation pulse (width, 1 μs; tip angle, 22.5°).The fit function is given by Equation 4, in conjunction with Equation 5 and Equation 6. Best-fit kinetic parameters: k0, 8.80 × 106 s−1, corresponding to a quenching rate constant of 1.8 × 109 M−1 s−1; kex, 5.37 × 107 M−1 s−1

Modulating the activity of short arginine-tryptophan containing antibacterial peptides with N-terminal metallocenoyl groups

• H. Bauke Albada,
• Alina-Iulia Chiriac,
• Michaela Wenzel,
• Maya Penkova,
• Julia E. Bandow,
• Hans-Georg Sahl and
• Nils Metzler-Nolte

Beilstein J. Org. Chem. 2012, 8, 1753–1764, doi:10.3762/bjoc.8.200

• of ~90 µM, indicating a potentially interesting therapeutic window. Both the killing kinetics and growth inhibition studies presented in this work point to a membrane-based mode of action for these two peptides, each having different kinetic parameters. Keywords: antimicrobial peptides; arginine

• synthesized and tested for antimicrobial activity. In this paper we add another metal to the spectrum of existing organometallic synAMPs and we provide a detailed assessment of the kinetic parameters of this peptide. Specifically, we describe the effect of the introduction of ruthenocenoyl (ruthenocene

Highly efficient cyclosarin degradation mediated by a β-cyclodextrin derivative containing an oxime-derived substituent

• Michael Zengerle,
• Florian Brandhuber,
• Christian Schneider,
• Franz Worek,
• Georg Reiter and
• Stefan Kubik

Beilstein J. Org. Chem. 2011, 7, 1543–1554, doi:10.3762/bjoc.7.182

• 1c, and the triazole-linked derivative 2a were also included in this study. Quantitative assay. The kinetic parameters for the reduction of GF concentration in solution mediated by 1b, 1c, and 2a were determined as described previously for other cyclodextrin derivatives [23]. Briefly, a buffered

Unusual behavior in the reactivity of 5-substituted-1H-tetrazoles in a resistively heated microreactor

• Bernhard Gutmann,
• Toma N. Glasnov,
• Tahseen Razzaq,
• Walter Goessler,
• Dominique M. Roberge and
• C. Oliver Kappe

Beilstein J. Org. Chem. 2011, 7, 503–517, doi:10.3762/bjoc.7.59

• magnitude. When 5-benzhydryl-1H-tetrazole was exposed to 220 °C in this type of flow reactor, decomposition to diphenylmethane was complete within 10 min. The mechanism and kinetic parameters of tetrazole decomposition under a variety of reaction conditions were investigated. A number of possible

Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis

• Ulrich Kunz and
• Thomas Turek

Beilstein J. Org. Chem. 2009, 5, No. 70, doi:10.3762/bjoc.5.70

• determination of kinetic parameters. The reaction is of industrial importance. It is the main process for production of formic acid. For the kinetic measurements two directly electrically heated and independently temperature regulated tubes in series were used. The same power supply delivers enough current for