150-13-0Relevant articles and documents
Rescuing auxotrophic microorganisms with nonenzymatic chemistry
Lee, Yunmi,Umeano, Afoma,Balskus, Emily P.
, p. 11800 - 11803 (2013)
Organic chemistry to the rescue: Two unrelated nonenzymatic chemical reactions can support the growth of auxotrophic E.-coli strains by generating essential nutrients in-situ. These biocompatible reactions, which take place in the presence of the organisms and are designed to interface with cellular metabolic processes, provide a means of linking the growth of an organism to the success of a nonbiological chemical transformation. Copyright
A general Staudinger protocol for solution-phase parallel synthesis
Lindsley, Craig W,Zhao, Zhijian,Newton, Randall C,Leister, William H,Strauss, Kimberly A
, p. 4467 - 4470 (2002)
The Staudinger reaction has been adapted for parallel synthesis by the application of fluorous-tethered triphenyl phosphine. The fluorous-tethered triphenylphosphine is expediently removed in parallel by FluoroFlash SPE columns to afford functionalized amines in high yields and purities.
Sulfonated covalent triazine polymer loaded with Pd nanoparticles as a bifunctional catalyst for one pot hydrogenation esterification reaction
Ravi, S.,Raza, A. Ahmed,Sheriff, A. K. Ibrahim,Tajudeen, S. Syed
, (2021)
Highly dispersed Pd nanoparticles over covalent triazine polymer functionalized with sulfonic acid groups (CTP-SO3H/Pd) were prepared by facile Friedel-Crafts reaction, post synthetic sulfonation and Pd immobilization method. The prepared catalyst was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption-desorption, inductively coupled plasma - optical emission spectrometry (ICP-OES), elemental analysis and X-ray photoelectron spectroscopy (XPS). The sulfonic acid groups were grafted into the terphenyl backbone and the presence of triazine functionality within the framework enabled the uniform dispersion of palladium nanoparticles over the polymer network. When used as a bifunctional catalyst in one pot hydrogenation-esterification (OHE) reaction, the CTP-SO3H/Pd exhibited good activity and stability. The performance of CTP-SO3H/Pd is due to the surface-active acid/metal sites and was evident from the yield of the product in the reaction. The catalyst was easily recovered by filtration and recycle tests showed that it could be re-used for at least five repetitive runs with minor loss of catalytic activity suggesting its potential utility in OHE reaction. A plausible mechanistic pathway for OHE reaction over CTP-SO3H/Pd was also proposed.
Gold(II) Porphyrins in Photoinduced Electron Transfer Reactions
Prei?, Sebastian,P?pcke, Ayla,Burkhardt, Lukas,Gro?mann, Luca,Lochbrunner, Stefan,Bauer, Matthias,Opatz, Till,Heinze, Katja
, p. 5940 - 5949 (2019)
In the context of solar-to-chemical energy conversion, inspired by natural photosynthesis, the synthesis, electrochemical properties and photoinduced electron-transfer processes of three novel zinc(II)-gold(III) bis(porphyrin) dyads [ZnII(P)–AuIII(P)]+ are presented (P: tetraaryl porphyrin). Time-resolved spectroscopic studies indicated ultrafast dynamics (kET1>1010 s?1) after visible-light excitation, which finally yielded a charge-shifted state [ZnII(P?+)–AuII(P)]+ featuring a gold(II) center. The lifetime of this excited state is quite long due to a comparably slow charge recombination (kBET2 ≈3×108 s?1). The [ZnII(P?+)–AuII(P)]+ charge-shifted state is reductively quenched by amines in bimolecular reactions, yielding the neutral zinc(II)–gold(II) bis(porphyrin) ZnII(P)–AuII(P). The electronic nature of this key gold(II) intermediate, prepared by chemical or photochemical reduction, is elucidated by UV/Vis, X-band EPR, gold L3-edge X-ray absorption near edge structure (XANES) and paramagnetic 1H NMR spectroscopy as well as by quantum chemical calculations. Finally, the gold(II) site in ZnII(P)–AuII(P) is thermodynamically and kinetically competent to reduce an aryl azide to the corresponding aryl amine, paving the way to catalytic applications of gold(III) porphyrins in photoredox catalysis involving the gold(III/II) redox couple.
A facile reduction of nitroarenes to anilines using FeCl 3·6H2O/indium
Yoo, Byung Woo,Choi, Jin Woo,Hwang, Sun Kyun,Kim, Dong Yoon,Baek, Heung Soo,Choi, Kyung Il,Kim, Joong Hyup
, p. 2985 - 2988 (2003)
Reduction of a variety of nitroaromatic compounds to the corresponding anilines occurs chemoselectively in high yields upon treatment with a new reduction system consisting of FeCl3·6H2O/indium in aqueous methanol.
Possible role of hydroxyl radicals in the oxidative degradation of folic acid
Patro, Birija S.,Adhikari, Soumyakanti,Mukherjee, Tulsi,Chattopadhyay, Subrata
, p. 67 - 71 (2005)
An unprecedented .OH radical-induced N-dealkylation of amines including folic acid is reported, the reaction proceeding via a direct hydrogen atom abstraction mechanism as revealed by pulse radiolysis experiments. Hydroxyl radicals have been found to cause oxidative N-dealkylation of amines including folic acid via a hydrogen atom transfer mechanism.
Characterization of the folate salvage enzyme p-aminobenzoylglutamate hydrolase in plants
Bozzo, Gale G.,Basset, Gilles J.C.,Naponelli, Valeria,Noiriel, Alexandre,Gregory III, Jesse F.,Hanson, Andrew D.
, p. 29 - 37 (2008)
Folates break down in vivo to give pterin and p-aminobenzoylglutamate (pABAGlu) fragments, the latter usually having a polyglutamyl tail. Pilot studies have shown that plants can hydrolyze pABAGlu and its polyglutamates to p-aminobenzoate, a folate biosynthesis precursor. The enzymatic basis of this hydrolysis was further investigated. pABAGlu hydrolase activity was found in all species and organs tested; activity levels implied that the proteins responsible are very rare. The activity was located in cytosol/vacuole and mitochondrial fractions of pea (Pisum sativum L.) leaves, and column chromatography of the activity from Arabidopsis tissues indicated at least three peaks. A major activity peak from Arabidopsis roots was purified 86-fold by a three-column procedure; activity loss during purification exceeded 95%. Size exclusion chromatography gave a molecular mass of ～200 kDa. Partially purified preparations showed a pH optimum near 7.5, a Km value for pABAGlu of 370 μM, and activity against folic acid. Activity was relatively insensitive to thiol and serine reagents, but was strongly inhibited by 8-hydroxyquinoline-5-sulfonic acid and stimulated by Mn2+, pointing to a metalloenzyme. The Arabidopsis genome was searched for proteins similar to Pseudomonas carboxypeptidase G, which contains zinc and is the only enzyme yet confirmed to attack pABAGlu. The sole significant matches were auxin conjugate hydrolase family members and the At4g17830 protein. None was found to have significant pABAGlu hydrolase activity, suggesting that this activity resides in hitherto unrecognized enzymes. The finding that Arabidopsis has folate-hydrolyzing activity points to an enzymatic component of folate degradation in plants.
FAST Hydrogenations as a Continuous Platform for Green Aromatic Nitroreductions
Manyar, Haresh,Moody, Thomas S.,Rahman, Md Taifur,Smyth, Megan,Wharry, Scott
, p. 581 - 586 (2020)
A continuous-flow packed-bed catalytic reactor has been developed for hydrogenation of aromatic nitrobenzoic acids in water to produce the corresponding anilines. These hydrogenations are green, more efficient, less consumptive, and safer than the conventional reduction process. Various industrially important aromatic amines have been produced in excellent yields and with high throughput. The optimized continuous-flow reduction process produces no detectable genotoxic intermediates, unlike the corresponding batch reduction. The reactor is modular in design and can be scaled up to produce several kilograms of product per day without extensive redesign.
Synthesis of six 8-quinolinate-based ruthenium complexes with high catalytic activity for nitroarene reduction
Jia, Wei-Guo,Cheng, Ming-Xia,Xu, Qiu-Tong,Gao, Li-Li,Yuan, Guozan
, p. 69 - 75 (2018)
Six ruthenium complexes were synthesized by treating different 2-substituted 8-hydroxyquinolinate ligands with [Ru(p-cymene)(μ-Cl)Cl]2. Their structures were fully characterized by a variety of techniques, including 1H and 13C NMR spectra, elemental analyses and infrared spectrometry. Additionally, single-crystal X-ray diffraction reveals that these ruthenium complexes possess similar half-sandwich structures. The mononuclear ruthenium building units are further linked into 1D or 2D supramolecular structures through non-covalent interactions, such as π?π stacking, hydrogen-bonding and C–H? halogen interactions. The catalytic activities of the six half-sandwich ruthenium complexes towards the hydrogenation of nitroarenes were explored under mild conditions. The ruthenium complexes displayed high catalytic activities in the synthesis of aromatic anilines from nitroarenes in the presence of NaBH4.
Oxidation of procainamide by diperiodatocuprate(III) complex in aqueous alkaline medium: a comparative kinetic study
Meti, Manjunath D.,Nandibewoor, Sharanappa T.,Chimatadar, Shivamurti A.
, p. 195 - 204 (2020)
A comparative study of uncatalysed and ruthenium(III) catalyzed oxidation of procainamide(PAH) was carried out spectrophotometrically using diperiodatocuprate(III) in aqueous alkali. Stoichiometry observed was 1:2 (PAH: DPC). The reaction was of first order in both catalyzed and uncatalyzed cases, with respect to [DPC] & [Ru(III)], less than unit order in [PAH] and [alkali]. Negative fraction in [periodate]. Other kinetic parameters viz., ionic strength, dielectric constant, temperature effect and intervention of free radical were also studied. The main oxidation products were characterized by different techniques. The activation parameters with respect to slow step of the mechanism, also the thermodynamic quantities were determined.
