124-07-2Relevant articles and documents
A safe and efficient flow oxidation of aldehydes with O2
Vanoye, Laurent,Aloui, Asma,Pablos, Mertxe,Philippe, Regis,Percheron, Aurelien,Favre-Reguillon, Alain,De Bellefon, Claude
, p. 5978 - 5981 (2013)
A safe, straightforward, and atom economic approach for the oxidation of aliphatic aldehydes to the corresponding carboxylic acids within a continuous flow reactor is reported. Typically, the reaction is performed at room temperature using 5 bar of oxygen in PFA tubing and does require neither additional catalysts nor radical initiators except for those already contained in the starting materials. In some cases, a catalytic amount of a Mn(II) catalyst is added. Such a flow process may prove to be a valuable alternative to traditionally catalyzed aerobic processes.
Transformations of peroxide products of olefin ozonolysis in tetrahydrofuran in reactions with hydroxylamine and semicarbazide hydrochlorides
Ishmuratov,Legostaeva,Garifullina,Botsman,Muslukhov,Ishmuratova,Tolstikov
, p. 928 - 933 (2014)
Treatment with hydroxylamine and semicarbazide hydrochlorides of peroxide products obtained by ozonolysis of olefins in tetrahydrofuran gives mainly carboxylic acids and their derivatives.
A green and efficient oxidation of alcohols by amphiphilic resin-supported gold nanoparticles in aqueous H2O2
Xie, Ting,Lu, Min,Zhang, Wenwen,Li, Jun
, p. 397 - 399 (2011)
A green and highly efficient oxidation of alcohols in aqueous H 2O2 using amphiphilic resin (PS-PEG-NH2)-supported gold nanoparticles is described. The reaction proceeded with excellent yields and selectivities, in particular, for nonactivated alcohols without base. The catalyst, in addition, could be readily recovered by simple work-up and reused several times without significant loss of its catalytic activity.
Pentasaccharide resin glycosides with multidrug resistance reversal activities from the seeds of: Pharbitis nil
Li, Jun,Wang, Wen-Qiong,Tang, Shuai,Song, Wei-Bin,Huang, Min,Xuan, Li-Jiang
, p. 52001 - 52009 (2017)
Resin glycosides are novel P-glycoprotein inhibitors. In order to evaluate their multidrug resistance (MDR) reversal activities, we isolated seven new resin glycosides, pharbitins A-G (1-7) from the seeds of Pharbitis nil. Their chemical structures were determined by extensive application of high resolution 2D NMR techniques, HRESIMS and chemical methods. Compounds 1-4 and 6 were evaluated for their MDR reversal activities in KB/VCR, A549/T and K562/ADR cells. Among them, compound 2 showed moderate MDR reversal activity in KB/VCR cells, and increased the cytotoxicity of vincristine by 2.2-fold when incorporated at 25 μM. A structure-activity relationship study revealed that substituting Rha′′ C-3 with a trans-cinnamoyl group improves the MDR reversal activity. Also, an intracellular Rh123 accumulation assay demonstrated that compound 2 could inhibit the function of P-gp.
Synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases
Brodl, Eveline,Ivkovic, Jakov,Tabib, Chaitanya R.,Breinbauer, Rolf,Macheroux, Peter
, p. 1487 - 1495 (2017)
Bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490?nm. In this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. These α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. The luciferase of Photobacterium leiognathi was found to convert these analogs and showed a reduced but significant bioluminescence activity compared to tetradecanal. This study showed the trend that aldehydes, both saturated and unsaturated, with longer chain lengths had higher activity in terms of bioluminescence than shorter chain lengths. The maximal light intensity of (E)-tetradec-2-enal was approximately half with luciferase of P. leiognathi, compared to tetradecanal. Luciferases of Vibrio harveyi and Aliivibrio fisheri accepted these newly synthesized substrates but light emission dropped drastically compared to saturated aldehydes. The onset and the decay rate of bioluminescence were much slower, when using unsaturated substrates, indicating a kinetic effect. As a result the duration of the light emission is doubled. These results suggest that the substrate scope of bacterial luciferases is broader than previously reported.
Pentasaccharide resin glycosides from ipoma pes-caprae
Yu, Bang-Wei,Luo, Jian-Guang,Wang, Jun-Song,Zhang, Dong-Ming,Yu, Shi-Shan,Kong, Ling-Yi
, p. 620 - 628 (2011)
Pescapreins XXI-XXX (1-10), pentasaccharide resin glycosides, together with the known pescapreins I-IV and stoloniferin III were isolated from the aerial parts of Ipoma pes-caprae (beach morning-glory). The pescapreins are macrolactones of simonic acid B, partially esterified with different fatty acids. The lactonization site of the aglycone, jalapinolic acid, was located at C-2 or C-3 of the second saccharide moiety. Their structures were established by a combination of spectroscopic and chemical methods. Compounds 1-10 were evaluated for their potential to modulate multidrug resistance in the human breast cancer cell line MCF-7/ADR. The combined use of these new compounds at a concentration of 5 μg/mL increased the cytotoxicity of doxorubicin by 1.5-3.7-fold.
Hydration of nitriles to amides in water by SiO2-supported Ag catalysts promoted by adsorbed oxygen atoms
Shimizu, Ken-Ichi,Imaiida, Naomichi,Sawabe, Kyoichi,Satsuma, Atsushi
, p. 114 - 120 (2012)
A series of silica-supported silver catalysts with similar Ag loading (5 or 7 wt%) but with different preparation methods (calcination in air and reduction by H2 or NaBH4) were prepared, and their structure was characterized by microscopy (STEM), X-ray absorption fine structure (XAFS), and CO-titration of surface oxygen atom. Ag is present as metal nanoparticle with a size range of 17-30 nm. Their surface was partially covered with oxygen atoms, and the surface coverage of the oxygen depends on the preparation condition. For hydration of 2-cyanopyridine as a test reaction, turnover frequency (TOF) per surface Ag species is estimated. TOF does not show a good correlation with Ag particle size, but it linearly increases with the coverage of the surface oxygen atoms on Ag particles. The Ag/SiO2 catalyst prepared by H 2 reduction at 700 °C shows the highest TOF and it acts as effective and recyclable heterogeneous catalyst for selective hydration of various nitriles to the corresponding amides. Kinetic and Raman spectroscopic studies suggest that the surface oxygen atom adjacent to Ag0 sites plays an important role in the dissociation of H2O.
A dicationic ionic liquid-modified phosphotungstate hybrid catalyst for the heterogeneous oxidation of alcohols with H2O2
Leng, Yan,Zhao, Pingping,Zhang, Mingjue,Chen, Guojian,Wang, Jun
, p. 1796 - 1801 (2012)
An ionic hybrid catalyst 1,1'-(butane-1,4-diyl)-bis(3-methylimidazolium) phosphotungstate (abbreviated [Dmim]1.5PW) has been prepared by anion-exchange of the divalent ionic liquid (IL) 1,1'-(butane-1,4-diyl)-bis(3- methylimidazolium) di(bromide) with the Keggin phosphotungstic acid H 3PW12O40, and characterized by IR, 1H NMR, 13C NMR, ESI-MS, TG, SEM, XRD, BET surface area measurements, elemental analysis, and melting point. The hybrid material was evaluated as a catalyst for the oxidation of alcohols with aqueous hydrogen peroxide under various conditions. The catalytic performance of [Dmim] 1.5PW was also compared with related catalysts bearing other cations or anions. The new hybrid [Dmim]1.5PW proved to be an efficient liquid-solid heterogeneous catalyst for H2O2-based oxidation of alcohols, with the advantages of high conversion and selectivity, easy recovery, and quite good reusability. Science China Press and Springer-Verlag Berlin Heidelberg 2012.
Identification of novel fatty acid glucosides from the tropical fruit Morinda citrifolia L.
Kim, Hye-Kyeong,Kwon, Min-Kyong,Kim, Jin-Nam,Kim, Chang-Kwon,Lee, Yeon-Ju,Shin, Hee Jae,Lee, Joongku,Lee, Hyi-Seung
, p. 238 - 241 (2010)
Two new fatty acid glucosides, 1,6-di-O-octanoyl-β-D-glucopyranose (1) and 6-O-(β-D-glucopyranosyl)-1-O-decanoyl-β-D-glucopyranose (2), were isolated from a methanol extract of the fruit of Morinda citrifolia L. along with five known saccharide fatty acid esters. The structures of these compounds were determined by combination of spectral and chemical analyses. These fatty acid glucosides exhibited inhibitory effect against copper-induced low-density lipoprotein oxidation. Compound 2 had the strongest effect, which was almost comparable to that of butylated hydroxytoluene.
Effects of Sulfobetaine-Sodium Dodecanoate Micelles on Deacylation and Indicator Equilibrium
Frescura, Vera L. A.,Marconi, Dilma M. O.,Zanette, Dino,Nome, Faruk,Blasko, Andrei,Bunton, Clifford A.
, p. 11494 - 11500 (1995)
Fractional micellar ionization, α, and micelle concentrations have been measured for mixed micelles of sodium dodecanoate (SDOD) and sulfobetaines (CnH2n+1N+Me2(CH2)3SO3-, SB3-n, n = 10, 12, 14, 16), and values of pHapp have been calculated from deprotonation of 1-dodecylpyridinium-4-aldoxime bromide.For 0.1 M total surfactant first-order rate constants of hydrolyses of 2,4-dinitrophenyl acetate and octanoate (DNPA and DNPO, respectively) and benzoic anhydride (Bz2O) go through maxima at a mole fraction of SDOD of ca. 0.5 for DNPA and DNPO and 0.8 for Bz2O.These rate maxima are fitted quantitatively in terms of reactions of OH- and dodecanoate ion on the assumption that sulfobetaine micelles increase the nucleophilicity of the carboxylate ion.This rate effect is ascribed to decreased hydration and ion-pairing of the dodecanoate ion in the mixed micelles, on the basis of 1H NMR spectrometry in mixtures of SDOD and SB3-14.Therefore, incorporation of dodecanoate ion in SB3-n slows reaction by "dilution" in the micelle, but this inhibition is offset by activation of the nucleophilic dodecanoate ion.
