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54 results on '"Armstrong, Robert"'

1. Self-assembly directed by NH...O hydrogen bonding: new layered molecular arrays derived from 4-tert- butylbenzoic acid and aliphatic diamines.

Author

Armstrong RS, Atkinson IM, Carter E, Mahinay MS, Skelton BW, Turner P, Wei G, White AH, and Lindoy LF

Subjects
Benzoic Acid chemistry, Computer Simulation, Crystallization, Diamines chemistry, Hydrogen Bonding, Kinetics, Macromolecular Substances, Magnetic Resonance Spectroscopy, Mass Spectrometry, Models, Chemical, Models, Molecular, Spectrophotometry, Infrared, Spectrum Analysis, Raman, Temperature, Benzoates chemistry, Chemistry methods, Oxygen chemistry, Quaternary Ammonium Compounds chemistry
Abstract

(1H) and (13)C NMR titrations in both CDCl(3) and CD(3)OD demonstrate that 4-tert-butylbenzoic acid interacts with both propane-1,2-diamine and propane-1,3-diamine to yield 1:2 host-guest complexes in these solvents. Based on this observation, the isolation of new three-dimensional molecular arrays through cocrystallization of the above diamines and 4-tert-butylbenzoic acid (in a 1:2 molar ratio) has been achieved. X-ray studies of these self-assembled structures show that they incorporate [propane-1,2-diamine x (4-tert-butylbenzoic acid)(2)] or [propane-1,3-diamine x (4-tert-butylbenzoic acid)(2)] hydrogen-bonded motifs. Three structural derivatives of the latter type (two monohydrate forms and one anhydrous form) have been characterized. The structures are compared with a previously described three-dimensional array based on the "parent" [ethane-1,2-diamine x (benzoic acid)(2)] motif. Similarities occur between each of the structures. In each, a two-dimensional "ionic" layer consisting of an extensive network of hydrogen bonds is sandwiched between two "less polar" aromatic ring-containing layers. In the respective ionic layers, the carboxylic acid protons have been transferred onto the amines to yield diammonium cations, with all ammonium protons being involved in hydrogen bonding. In part, the adoption of these unusual layered structures seems to reflect a tendency toward maximization of both the number and strengths of the hydrogen bond interactions in the respective ionic layers.

Published
2002
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2. Detemination of Fe-ligand bond lengths and the Fe-N-O bond angles in soybean ferrous and ferric nitrosylleghemoglobin a using multiple-scattering XAFS analyses

Author

Rich, Anne M., Ellis, Paul J., Tennant, Linda, Wright, Peter E., Armstrong, Robert S., and Lay, Peter A.

Subjects
Biochemistry -- Research, Ligands -- Research, Proteins -- Research, Biological sciences, Chemistry
Abstract

Ferric nitrosylleghemoglobin and XAS experiments carried out on frozen aqueous solutions of Lb (super)II NO and Lb (super)III NO are discussed. Multiple-scattering analyses of the XAFS data are presented.

Published
1999

3. Determination of iron-ligand bond lengths in ferric and ferrous horse heart cytochrome c using multiple scattering analyses of XAFS data

Author

Cheng, Ming-Chu, Rich, Anne M., Armstrong, Robert S., Ellis, Paul J., and Lay, Peter A.

Subjects
Ligands -- Research, Cytochrome c -- Research, Iron in the body -- Research, Electron transport -- Research, X-ray crystallography -- Usage, X-ray spectroscopy -- Usage, Chemistry
Abstract

Iron-ligand bond lengths in ferric and ferrous horse heart cytochrome c have been determined through use of multiple scattering (MS) analyses of X-ray absorption fine structure (XAFS) data. Bond lengths determined with this method are more accurate than those based on X-ray crystallographic data and show small differences in bond lengths consistent with near-zero reorganizational energy terms required for fast electron-transfer properties of ferricyt c and ferrocyt c.

Published
1999

4. How to Synthesise High Purity, Crystalline d‐Glucaric Acid Selectively

Author

Armstrong, Robert D., Kariuki, Benson M., Knight, David W., and Hutchings, Graham J.

Subjects
chemistry.chemical_classification, Glucaric acid, 010405 organic chemistry, Chemistry, Communication, Organic Chemistry, D-Glucaric Acid, Glucaric Acid Synthesis | Very Important Paper, Carbohydrates, Polymer, 010402 general chemistry, 01 natural sciences, Glucaric Acid, Communications, 0104 chemical sciences, Chemoselectivity, Azeotrope, Yield (chemistry), Molecule, Organic chemistry, Physical and Theoretical Chemistry, Platform molecule
Abstract

Glucaric acid has potential applications in food, pharmaceutical and polymer industries yet no methodology exists within the public domain for isolation of this key bio-derived platform molecule as a pure, crystalline solid. Here we demonstrate the difficulties, which arise in doing so and report development of a process for derivation of free-glucaric acid from its Ca2+/K+ glucarate salts, which are both commercially available. Employing Amberlyst-15 (H+) exchange resin and azeotrope drying, powdered glucaric acid is prepared at > 99.96 % purity in 98.7 % dry yield.

Published
2017

5. Total synthesis of calyculin C

Author

Ogawa, Anthony K. and Armstrong, Robert W.

Subjects
Phosphatases -- Research, Chemical inhibitors -- Research, Enzyme inhibitors -- Research, Chemistry
Abstract

An analysis of the total synthesis of calyculin C showed that the diastereoselectivity characterizing C10-C11-propionate stereocenters exhibited a remote protecting group effect. This effect was observed for the serine/threonine phosphatase inhibitor's C1-C25 fragment. Other synthesis results include the development of C25-C26 double bond through a deprotected C26-C37 phosphonium salt and confirmation of stereochemistry at C34.

Published
1998

6. A case study of employing spectroscopic tools for monitoring reactions in the developmental stage of a combinatorial chemistry library

Author

Luo, Ying, Ouyang, Xiaohu, Armstrong, Robert W., and Murphy, Martin M.

Subjects
Gums and resins -- Research, Chemical reactions -- Research, Non-destructive testing -- Research, Amines -- Research, Alkylation -- Research, Biological sciences, Chemistry
Abstract

A study was conducted to characterize a way to monitor a reaction sequence on resin. Magic angle spinning nuclear magnetic resonance (NMR) and Fourier transform infrared were used for the nondestructive monitoring process. The identity of acrylate was determined using 13C NMR while alkylation was carried out to form the tetrasubstituted amine salt with allylic bromide. Results indicated that the combination of techniques can effectively support the nondestructive testing of resins.

Published
1998

7. A novel cleavage technique to generate small molecule compounds and libraries via a two-resin system

Author

Ouyang, Xiaohu, Armstrong, Robert W., and Murphy, Martin M.

Subjects
Amines -- Research, Organic compounds -- Synthesis, Gums and resins -- Research, Biological sciences, Chemistry
Abstract

Research was conducted to investigate the application of the Hofmann elimination of tetrasubsituted amine salts on solid-phase resin to produce diverse combinatorial libraries of trisubstituted amines. The diversity of disubstituted amines, cyclic and noncyclic was examined as a second step of alkylation while quaternary ammonium compounds were bound by overnight agitation. Results showed the success of amberlite-promoted Hofmann eliminations in solution-phase organic syntheses.

Published
1998

8. The Ugi five-component condensation using CO2, CS2, and COS as oxidized carbon sources

Author

Keating, Thomas A. and Armstrong, Robert W.

Subjects
Condensation products (Chemistry) -- Research, Alcohol -- Research, Amides -- Research, Biological sciences, Chemistry
Abstract

Investigations into the Ugi five-component condensation (5CC), which allows the synthesis of carbamate-protected aminoamide, aminothioamide and thiourea-thioamide core structures in a single reaction, were conducted. The 5CC is the condensation of an amine, a carbonyl compound, an alcohol, an isocyanide and carbon dioxide to produce an alpha-(alkoxylcarbonylamino)amide. Results demonstrate that the yields of product range from poor to very good and reveal that methanol is clearly the superior alcohol substrate.

Published
1998

9. A remarkable two-step synthesis of diverse 1,4-benzodiazepine-2,5-diones using the Ugi four-component condensation

Author

Keating, Thomas A. and Armstrong, Robert W.

Subjects
Anticonvulsants -- Analysis, Antineoplastic agents -- Analysis, Organic compounds -- Synthesis, Biological sciences, Chemistry
Abstract

A novel method for the synthesis of 1,4-benzodiazepine-2,5-diones (BZDs) was developed based on an Ugi four-component condensation mediated by isocyanide(1-isocyanocyclohexene). The novel two-step procedure for the synthesis of diverse 1,4-benzodiazepine-2,5-diones takes advantage of the maximal input diversity offered by the Ugi four-component condensation. Furthermore, the synthetic process is characterized by the conformational isomerization of the BZD skeleton and slow alkyl substitution.

Published
1997

10. Raman excitation profiles of C70 in benzene solution. Assignment of the electronic spectrum in the 380 - 510-nm region

Author

Gallagher, Sean H., Armstrong, Robert S., Bolskar, Robert D., Lay, Peter A., and Reed, Christopher A.

Subjects
Carbon allotropes -- Analysis, Benzene -- Analysis, Chemistry
Abstract

The resonance Raman spectrum of C70 was examined in benzene employing 11 laser excitation energies across the main visible absorption band (MVAB) of C70 between 514.5 and 406.7 nm. Three electronic transitions under the MVAB were determined and assigned definitively: the HOMO - 4(e2') -> LUMO + 1 (e1') transition in the 514/501-nm excitation region, the HOMO - 5 (e1') -> LUMO + 1 (e1') transition in the 476/472-nm excitation region and the HOMO (a2') -> LUMO + 2 (a1') in the 457/452-nm excitation region. The REPs indicated that these three electronic transitions are vibronically coupled to the strong electronic transition at 382 nm.

Published
1997

11. A remarkable two-step synthesis of diverse 1,4-benzodiazepine-2,5-diones using the Ugi four-component condensation

Author

Keating, Thomas A. and Armstrong, Robert W.

Subjects
Ring formation (Chemistry) -- Research, Benzodiazepines -- Structure-activity relationships, Condensation products (Chemistry) -- Research, Biological sciences, Chemistry
Abstract

The Ugi reaction was used in synthesizing diverse 1,4-benzodiaepine-2,5-diones (BZDs) 1 to derive the precursor alpha-acylaminoamide 3. The Ugi four-component condensation is also considered for a diverse compound class using a convertible isocyanide. The method improves initial BZD tests and offers greater potential for molecular diversity.

Published
1996

12. Generation of C-glycoside peptide ligands for cell surface carbohydrate receptors using a four-component condensation on solid support

Author

Sutherlin, Daniel P., Stark, Todd M., Hughes, Robert, and Armstrong, Robert W.

Subjects
Carbohydrates -- Analysis, Condensation -- Research, Glycosides -- Analysis, Ligands (Biochemistry) -- Analysis, Biological sciences, Chemistry
Abstract

The solid phase Ugi four-component condensation with various functionalized C-glycosides which can utilize different protecting group techniques is used to demonstrate the solid phase synthesis of glycomimetic candidiates which structurally resemble cell surface carbohydrates. It is touted as a simple yet highly efficient method for attaining rapid diversity in libraries focusing on carbohydrate receptor ligands. It is demonstrated through the synthesis of eight monosaccharides and disaccharides and a 96-well, 192-compound library of glycomimetics targeting the receptors of sialyl Lewis x.

Published
1996

13. X-ray crystallographic study of the ruthenium blue complexes [Ru2Cl3(tacn)2](PF6)2.4H2O, [Ru2Br3(tacn)2](PF6)2.H2O, and [Ru2I3(tacn)2]: steric interactions and the Ru-Ru 'bond length'

Author

Clucas, Wendy A., Armstrong, Robert S., Buys, Irmi E., Hambley, Trevor W., and Nugent, Kerry W.

Subjects
Ruthenium -- Analysis, Ligands -- Analysis, Complex compounds -- Analysis, Coordination compounds -- Analysis, Chemistry
Abstract

The crystal structure of [Ru2Cl3(tacn)2]2+, [Ru2Br3(tacn)2]3+ and [Ru2I3(tacn)2]3+ were analyzed by Raman spectroscopy to determine the mechanims that affect their steric interactions. The tridentate tacn ligands of the ruthenium blue complexes exhibited higher steric hindrance compared to the unidentate NH3 ligands. Furthermore, steric hindrance between the hydrogen and alpha-carbons of the tacn and halide bridges of the ligands increases the Ru-X-Ru bond angles.

Published
1996

14. Synthesis and conformational analysis of the multidrug resistance-reversing agent hapalosin and its non-N-methyl analog

Author

Dinh, Tam Q., Du, Xiaohui, and Armstrong, Robert W.

Subjects
Peptides -- Synthesis, Organic compounds -- Synthesis, Conformational analysis -- Research, Biosynthesis -- Research, Biological sciences, Chemistry
Abstract

Synthesis of hapalosin by chelation-controlled reduction of a gamma-amino-beta-keto-ester and cycloamidation revealed the synthetic hapalosin as a 2:3:1 mixture of conformers while its non-N-Me analog exists as a single conformer. Their conformations are determined by the configuration of the amide bond. The major conformer has an s-cis amide bond while the minor conformer as well as the non-N-Me analog have s-trans amide bonds. The major conformer of hapalosin and the non-N-Me analog have vastly different conformations. On the other hand, the minor conformer and the non-N-Me analog have very similar conformations.

Published
1996

15. Synthesis of the C1-C25 fragment

Author

Scarlato, Gerard R., DeMattei, John A., Chong, Lee S., Ogawa, Anthony K., Lin, Mavis R., and Armstrong, Robert W.

Subjects
Organic compounds -- Synthesis, Stereochemistry -- Analysis, Biological sciences, Chemistry
Abstract

Synthesis of the C1-C25 spiroketal core fragment of calyculin C was conducted based on an allylboration strategy. The process focused on the initial disconnection of the C25-C26 double bonds which leads to the formation of a product with two similar functional density. The desired stereochemistry was acquired by the initial synthesis of the C21-C25 spiroketal core and its subsequent homologation based on chiral allylboration strategy.

Published
1996

16. Synthesis of the C26-C37 fragment and model Wittig couplings

Author

Ogawa, Anthony K., DeMattei, John A., Scarlato, Gerard R., Tellew, John E., Chong, Lee S., and Armstrong, Robert W.

Subjects
Organic compounds -- Synthesis, Sugars -- Analysis, Chemical bonds -- Analysis, Biological sciences, Chemistry
Abstract

A functionalized C26-C37 oxazole fragment was synthesized based on a stereospecific method that utilizes an amino acid-based strategy. The method was based on the disconnection of the C33-N3 amide bond for the efficient use of C33-C37 aza-sugar fragment and the C26-C32 fragment. The synthesis of enantiomeric C33-C37 fragments depends on the abundant supply of aldopentoses and requires a double inversion at the C4 of D-ribose. The production of the C26-C37 fragment was based on the identification of the proper sequence of phosphonium salt formation and debenzylation.

Published
1996

17. Synthesis of the C1-C21 fragment of the serine/threonine phosphatase inhibitor tautomycin

Author

Maurer, Karl W. and Armstrong, Robert W.

Subjects
Serine -- Research, Threonine -- Research, Enzyme inhibitors -- Research, Cyclic compounds -- Research, Chloromethyl group -- Research, Biological sciences, Chemistry
Abstract

The present route for the synthesis of tautomycin allows isotopic labeling and minor structural modification. The spiroketal compound, incorporating the C-1 to C-21 fragment of tautomycin, is synthesized from methaneboric acid. Stereocenters at C-3 and C-13 to C-21 are put up in the spirocyclic half of tautomycin by Matteson's stereospecific insertion of chloromethylene into a boron-carbon bond as guided by the pinanediol chiral auxiliary. The two spirocyclic halves undergo coupling in the presence of Cr/Ni and generate a structure with the C-1 to C-21 portion of tautomycin.

Published
1996

18. Postcondensation modifications of Ugi four-component condensation products: 1-isocyanocyclohexene as a convertible isocyanide: mechanism of conversation, synthesis of diverse structures, and demonstration of resin capture

Author

Keating, Thomas A. and Armstrong, Robert W.

Subjects
Condensation products (Chemistry) -- Research, Isocyanates -- Research, Cyclohexane -- Research, Chemistry
Abstract

The use of 1-isocyanocyclohexene as an 'universal isocyanide' input in the Ugi one-pot condensation enables the postcondensation conversion of its Ugi four-component product, alpha-(acylamino) amides such as cyclohexenamide, into a variety of functionalities. These include carboxylic acids, esters, thioesters, pyrroles, sugars and 1,4-benzodiazepine-2,5-diones. The trapping Ugi products of a solution reaction onto a solid support resin is also carried out.

Published
1996

19. Dehydroamino acid derivatives from D-arabinose and L-serine: synthesis of models for the azinomycin antitumor antibiotics

Author

Moran, Edmund J., Tellew, John E., Zuchun Zhao, and Armstrong, Robert W.

Subjects
Amino acids -- Research, Serine -- Analysis, Antineoplastic antibiotics -- Analysis, Biological sciences, Chemistry
Abstract

Key precursors for the production of extremely functionalized dehydroamino acid derivatives, upon condensation with glycyl phosphonates, resulted from the preparation of aldehydes from D-arabinose. The azabicyclo (3.1.0) hex-2-ylidine ring systems believed to be present in the azinothycin antitumor antibiotics, resulted from brominatin and intramolecular addition/elimination.

Published
1993

20. Effect of electrolyte concentration on axial anion ligation in manganese(III) meso-tetraphenylporphyrin chlorides

Author

Foran, Garry J., Armstrong, Robert S., Crossley, Maxwell J., and Lay, Peter A.

Subjects
Porphyrins -- Research, Chemistry
Abstract

The effect of increasing electrolyte concentration on axial ligation in a series of substituted manganese(III) 5,10,15, 20-tetraarylporphyrin chlorides was investigated. It was found that increasing the concentration of Bu4N(super 1+)(BF4 super 1-) promotes the dissociation of the axial chloride ligand of the metalloporphyrins. Furthermore, the responsiveness of these manganese(III) prophyrins to this electrolyte-promoted axial-anion dissocation depends on the character of the peripheral aryl substituent.

Published
1992

21. Stereoselective synthesis of (E)- and (Z)-1-azabicyclo(3.1.0)hex-2-ylidene dehydroamino acid derivatives

Author

Armstrong, Robert W., Tellew, John E., and Moran, Edmund J.

Subjects
Bromine -- Research, Cyclic compounds -- Research, Olefins -- Research, Elimination reactions -- Research, Biological sciences, Chemistry
Abstract

The (E)- and (Z)-1-azabicyclo(3.1.0)hex-2-ylidine dehydroamino acid compounds can be prepared from the bromination of dehydroamino acids followed by cyclization of the olefinic beta-bromodehydroamino acid derivatives. The bromination process involves the introduction of either N-bromosuccinimide or Br2/2,6-lutidine which promotes the formation of vinyl bromides with high diastereoselectivity. Moreover, an intramolecular Michael addition-elimination with retention of olefin configuration characterizes the cyclization process which eventually forms 1-azabicyclo(3.1.0)hex-2-ylidine ring structures that correspond to azinomycin antibiotics.

Published
1992

22. Synthesis of alpha-methyl 1',2'-dideoxycellobioside: a novel C-disaccharide

Author

Armstrong, Robert W. and Teegarden, Bradley R.

Subjects
Carbohydrates -- Research, Organic compounds -- Synthesis, Olefins -- Usage, Biological sciences, Chemistry
Abstract

A stereoselective route to beta-disaccharides with methylene in place of oxygen links involves bromine-catalyzed 6-endo-trig cyclization of D-arabinose-derived E olefins. This method is used to prepare alpha-methyl 1',2'- dideoxycellobioside. The use of trans-actonide olefins prevents furan formationdue to restricted rotation about the glycosidic bond. Stereocenters at the exo-anomeric carbon, which is prevented from taking part in the cyclization, are thus stabilized. This allows a unique staggered conformation for the disaccharide.

Published
1992

23. In situ Fe K-edge X-ray absorption spectroscopy of a nitrosyl iron(II) porphyrin adduct adsorbed on a high-area carbon electrode in aqueous electrolytes

Author

Bae, In Tae, Tolmachev, Yuriy, Mo, Yibo, Scherson, Daniel, Scheidt, W. Robert, Ellison, Mary K., Ming-Chu Cheng, Armstrong, Robert S., and Lay, Peter A.

Subjects
Chemistry, Inorganic -- Research, Iron -- Physiological aspects, X-ray spectroscopy -- Usage, Porphyrins -- Physiological aspects, Carbon -- Physiological aspects, Electrolytes -- Usage, Chemistry
Abstract

Research has been conducted on the nitrosyl iron(II) porphyrin adduct adsorbed on the electrode surface. The results of the in situ Fe K-edge X-ray absorption spectroscopic study of the properties of this adduct are reported.

Published
2001

24. Preparation of spiro hydroxy S-methylisothioureas from cyclic ketones

Author

McAlpine, Indrawan J. and Armstrong, Robert W.

Subjects
Organic compounds -- Synthesis, Ketones -- Research, Biological sciences, Chemistry
Abstract

A mild procedure for preparing spiro alpha-hydroxy S-methylisothioureas from cyclic ketones is discussed. It involves the derivation of 2-thiohydantoin 4-imine via an Ugi four-component condensation using benzyl isocyanide followed by the reduction of the 4-imine with sodium cyanoborohydride and iodine in methylene choride and tetrahydrofuran. The latter affords an alpha-benzylamino thiourea which may be converted into an alpha-hydroxy thiourea. Meanwhile, modification of the process yields alpha-hydroxy S-methylisothiourea.

Published
1996

25. Demonstrating oxygen loss and associated structural reorganization in the lithium battery cathode Li[[Ni.sub.0.2][Li.sub.0.2][Mn.sub.0.6]][O.sub.2]

Author

Armstrong, Robert A., Thackeray, Michael M., Bruce, Peter G., Holzapfel, Michael, Novak, Petr, Johnson, Christopher S., and Sun-Ho Kang

Subjects
Lithium cells -- Research, Lithium cells -- Properties, Cathodes -- Research, Electrodes -- Research, Chemistry
Abstract

Direct evidence for oxygen evolution associated with charging a layered lithium-manganese-nickel-oxide electrode with [Li.sub.2]Mn[O.sub.3]-like character beyond the typical limit for deintercalation (4.5 V) is presented. The removal of [Li.sub.2]O from the electrode structure, on account of the charging across the 4.5 V plateau results in a layered M[O.sub.2] electrode structure in which the M octahedral sites are occupied almost exclusively by manganese and nickel.

Published
2006

26. Determination of the nature of the heme environment in nitrosyl indoleamine 2,3-dioxygenase using multiple-scattering analyses of x-ray absorption fine structure

Author

Aitken, Jade B., Thomas, Sushila E., Stocker, Roland, Thomas, Shane R., Takikawa, Osamu, Lay, Peter A., and Armstrong, Robert S.

Subjects
Absorption -- Research, Nitrogen oxide -- Optical properties, Biological sciences, Chemistry
Abstract

The first directional structural information about the iron center for multiple-scattering analyses of x-ray absorption fine structure data on the nitrogen oxide (NO) adducts of indoleamine 2,3-dioxygenase (IDO) and analyses of x-ray absorption near-edge structure (XANES) is presented. The results show that the blocking of heme site to O2 binding and conformational changes induces the breaking of the Fe-N(sub member of) bond, which is an important mechanism by which NO inhibits IDO in vitro and in vivo.

Published
2004

27. Bonding in HNO-myoglobin as characterized by X-ray absorption and resonance Raman spectroscopies

Author

Immoos, Chad E., Levina, Aviva, Sulc, Filip, Aitken, Jade B., Farmer, Patrick J., Armstrong, Robert, Czarnecki, Kazimierz, Lay, Peter, and Bocian, David F.

Subjects
Nitro compounds -- Structure, Nitro compounds -- Chemical properties, Myoglobin -- Structure, Myoglobin -- Chemical properties, Raman spectroscopy -- Usage, Chemistry
Abstract

A resonance Raman (RR) and X-ray absorption characterization of Mb-HNO, which yields new information on bonding within this species, is discussed. The results provided definitive evidence for the structure of Mb-HNO, which supports the structure deduced on the basis of NMR experiments and is the first structural characterization of an HNO bound to a heme protein.

Published
2005

28. Synthesis of the C(sub 59)N(super +) carbocation. A monomeric azafullerene isoelectronic to C60

Author

Kee-Chan Kim, Hauke, Frank, Hirsch, Andreas, Boyd, Peter D.W., Carter, Elizabeth, Reed, Christopher A., Lay, Peter A., and Armstrong, Robert S.

Subjects
Oxidation-reduction reaction -- Methods, Carbon -- Chemical properties, Chemistry
Abstract

The monomeric C59N(super +) cation, which is isoelectronic with C60, can be isolated as a carborane anion salt. An azafullerene analogue of C60 is accessible through chemical oxidation of dimeric (C59N)(sub 2) with a strong electron-hole oxidant.

Published
2003

29. Parallel synthesis of tamoxifen and derivatives on solid support via resin capture

Author

Brown, S. David and Armstrong, Robert W.

Subjects
Tamoxifen -- Analysis, Estrogen -- Antagonists, Biological sciences, Chemistry
Abstract

Solid support via resin capture method was used to synthesize the estrogen antagonist tamoxifen and its derivatives. Isolation of the resin was done by filtration and purified by washing. Results show that these derivative forming reactions are dependent on resin capture and a silicon linker. Modification of each position about the ethylene core can be done using resin capture with the appropriate choice of alkyne, aryl halide and cleavage conditions.

Published
1997

30. Synthesis of benzofuran derivatives on solid support via SmI2-mediated radical cyclization

Author

Du, Xiaohui and Armstrong, Robert W.

Subjects
Ring formation (Chemistry) -- Analysis, Scission (Chemistry) -- Analysis, Furans -- Analysis, Biological sciences, Chemistry
Abstract

An alternative method of synthesizing benzofuran derivatives was designed through SmI2-mediated aryl radical cyclizations on solid support. The design featured the utilization of polyethylene glycol-grafted resins as coupling medium. NMR spectra of the crude products have shown the predominance of cyclized products with a small percentage of the reduced products. Reduction of the aryl iodide was a minor side reaction.

Published
1997

31. Cyclobutenedione derivatives on solid support: Toward multiple core structure libraries

Author

Tempest, Paul A. and Armstrong, Robert W.

Subjects
Molecular structure -- Observations, Chemical reactions -- Observations, Chemistry
Abstract

The squaric acid derived synthesis of fused aromatic and heteroaromatic cores was identified as a reaction platform for the generation of MCSLs. The first route involved a halogenated aryl ether on Wang resin, generated through the Mitsunobu reaction, coupled with tributyltin isopropyl squarate under Stille conditions. The second route avoided the synthesis of the stannylated squarate.

Published
1997

32. Analogs incorporating trans-4-hydroxy-L-proline that reverse multidrug resistance better than hapalosin

Author

Dinh, Tam Q., Smith, Charles D., and Armstrong, Robert

Subjects
Drug resistance -- Research, Peptides -- Synthesis, Biological sciences, Chemistry
Abstract

The synthesis of the four proline analogs of the cyclic depsipeptide hapalosin is described. The anti-multidrug resistance properties of the synthetic hapalosin and its analogs were determined by cytotoxicity and drug accumulation assays using MNC-7/ADR cells. The results showed the importance of a free hydroxyl and an aromatic group in the anti-MDR activities of the compounds.

Published
1997

33. The synthesis of C-trisaccharides exploiting the stereochemical diversity of a central sugar

Author

Sutherlin, Daniel P. and Armstrong, Robert W.

Subjects
Sugars -- Research, Organic compounds -- Synthesis, Chemistry
Abstract

A general approach for the synthesis of C-trisaccharides bearing 1,2 sugar branching was developed using the H type I blood group determinant. Two pendant sugars were attached to the terminus of the trisaccharide. A central hexose core was created for the C-trisaccharide and permutational mutations to these core caused changes to the trisaccharide's overall conformation. The steps to the synthesis of more trisaccharides bearing a variety of structures are discussed.

Published
1996

34. Synthesis of tetrasubstituted ethylenes on solid support via resin capture

Author

Brown, S. David and Armstrong, Robert W.

Subjects
Ethylene compounds -- Analysis, Organic compounds -- Synthesis, Chemistry
Abstract

Tetrasubstituted ethylenes may be synthesized on a solid support by means of resin capture. Platinum-catalyzed diboration of alkynes yields bis(boryl)alkenes. The bis(boryl)alkenes are then monoalkylated in a solution Suzuki reaction with halide substrates, then reacted in the same manner again with a resin-bound halide. A library may thus be generated of alkyl, benzyl, allyl, vinyl and aryl halides and stored on resin.

Published
1996

35. A convergent synthesis of the multidrug resistance-reversing agent hapalosin

Author

Dinh, Tam Q. and Armstrong, Robert W.

Subjects
Peptides -- Synthesis, Organic compounds -- Synthesis, Biological sciences, Chemistry
Abstract

The acid chloride coupling method was employed to synthesize hapalosin, a cyclic depsipeptide which can contravene P-glycoprotein-mediated multidrug resistance in vitro. The procedure, which produced a 13% yield of hapalosin, involved the coupling of a synthetic amino alcohol and ester acid, the macrolactonization of a hydroxyacid under Mukaiyama conditions, and deprotection of the TBS ether of the macrolide.

Published
1995

36. Radio frequency tag encoded combinatorial library method for the discovery of tripeptide-substituted cinnamic acid inhibitors of the protein tyrosine phosphatase PTP1

Author

Moran, Edmund J., Sarshar, Sepehr, Cargill, John F., Shahbaz, Manouchehr M., Lio, Anna, Mjalli, Adnan M.M., and Armstrong, Robert W.

Subjects
Chemical inhibitors -- Analysis, Phosphatases -- Analysis, Chemistry
Abstract

A new combinatorial library method involving radio frequency encodable microchip with a polypropylene capsule of derivatized polystyrene suitably identifies novel protein tripeptide-substituted cinnamic acid inhibitors of protein tyrosine phosphatase. A tripeptide amide acetylated at the N-terminus is used as the library substrate. The library reveals glutamate residues in most potent inhibitors however CinnGEL and CinnGEE lack this position. Electron density maps of protein surface reveal an aggregate of positively charged clusters.

Published
1995

37. D-term scattering in the resonance Raman spectrum of C60

Author

Gallagher, Sean H., Armstrong, Robert S., Lay, Peter A., and Reed, Christopher A.

Subjects
Carbon allotropes -- Research, Raman effect -- Research, Chemistry
Abstract

Band analysis of the electronic spectrum of C60 in toluene and resonance Raman (RR) spectra of C60 in toluene support the involvement of D-term scattering in the significant non-adiabatic vibronic coupling between few excited electronic states of C60. Spectral data suggest the involvement of vibronic coupling in the transfer of intensity from C state to A state. Examination of the influence of solvatochrome on the electronic spectrum of C60 indicates the participation of A-term, B-term and A-term/B-term interference scattering and Jahn-Teller effects in the RR scattering mechanism.

Published
1994

38. Novel interstrand cross-links induced by the antitumor antibiotic carzinophilin/azynomycin

Author

Armstrong, Robert W., Salvati, Mark E., and Nguyen, Michael

Subjects
Structure-activity relationships (Biochemistry) -- Research, Tumor antigens -- Research, Chemistry
Abstract

Carzinophilin is an antitumor antibiotic which is found to cause significant DNA damage due to cross-link formation. It is discovered that bifunctional alkylation of carzinophilincauses interstrand cross-links in the major groove between G and certain purine residues. This is shown by the rational design of synthetic oligonucleotides containing the bases inosine and 7-deazaguanine at the target alkylation sites.

Published
1992

39. Stereoselective synthesis of 1-azabicyclo(3.1.0)hex-2-ylidene dehydroamino acid derivative related to the azinomycin antitumor antibiotics

Author

Armstrong, Robert W. and Moran, Edmund J.

Subjects
Antineoplastic agents -- Structure-activity relationships, Organic compounds -- Synthesis, Chemistry
Abstract

The successful stereoselective synthesis of 1-azabicyclo(3.1.0)hex-2-ylidene acetophenone provides a potential route to thepractical synthesis of azinomycins. Azinomycins are potent anti-leukemia drugs presently extracted from Streptomyces griseofuscus. The active component of azinomycin is the dehydroamino acid containing the 1-azabicyclo(3.1.0)hex-2-ylidene ring system. The key step in the synthesis is the intramolecular cyclization of aziridine, accomplished through addition of triethylamine at 50 degC. The yield is 75% Z isomer.

Published
1992

40. Total synthesis of motuporin (nodularin-V)

Author

Bauer, Shawn M. and Armstrong, Robert W.

Subjects
Enzyme inhibitors -- Research, Phosphatases -- Research, Proteins -- Synthesis, Cyclic compounds -- Research, Chemistry
Abstract

Research was conducted to examine the total synthesis of motuporin. The objective was to analyze the varied functionality of the molecule as well as to gain an insight into the synthesis of a number of inhibitors in the nodularin class. It was hypothesized that in the corresponding pentapeptide structure, the residue should also be in the active site and hence would be a good choice for modification and analogue studies.

Published
1999

41. Determination of iron - ligand bond lengths in horse heart met- and deoxymyoglobin using multiple-scattering XAFS analyses

Author

Rich, Anne M., Armstrong, Robert S., Ellis, Paul J., Freeman, Hans C., and Lay, Peter A.

Subjects
Myoglobin -- Research, Hemoproteins -- Research, Blood proteins -- Research, Metalloproteins -- Research, Spectrum analysis -- Usage, Chemistry
Abstract

MS XAFS spectroscopic methods were used to analyze horse heart met- and deoxy-myoglobin. The study provides examples of both the strengths and weaknesses of XAFS as a tool for the study of metalloproteins. The new values of the metal-ligand bond lengths in horse heart met- and deoxy-myoglobin have probable errors in the 0.02-0.03 A range in comparison to the figures derived for well-refined crystal structures at a certain resolution.

Published
1998

42. Determination of the Fe-ligand bond lengths and Fe-N-O bond angles in horse heart ferric and ferrous nitrosylmyoglobin using multiple-scattering XAFS analyses

Author

Rich, Anne M., Armstrong, Robert S., Ellis, Paul J., and Lay, Peter A.

Subjects
Myoglobin -- Research, Iron compounds -- Research, Biomolecules -- Research, Chemistry
Abstract

Multiple-scattering X-ray absorption fine structure analyses were conducted to determine the bond lengths between iron and its ligand as well as the bond angles formed by iron, nitrogen and oxygen in ferrous nitrosylmyoglobin from horse heart. The distances between iron and nitrogen are 2.00, 2.05 and 1.75 angstrom units for the pyrrole, imidazole and nitric oxide ligands respectively. The bond angle between iron, nitrogen and oxygen is 150 degrees.

Published
1998

45. Ofatumumab versus Teriflunomide in Multiple Sclerosis

Author

Hauser S. L., Bar-Or A., Cohen J. A., Comi G., Correale J., Coyle P. K., Cross A. H., de Seze J., Leppert D., Montalban X., Selmaj K., Wiendl H., Kerloeguen C., Willi R., Li B., Kakarieka A., Tomic D., Goodyear A., Pingili R., Haring D. A., Ramanathan K., Merschhemke M., Kappos L., Stephen L Hauser, Ludwig Kappos, Amit Bar-Or, Jeffrey A Cohen, Giancarlo Comi, Jorge Correale, Patricia K Coyle, Anne Cross, Jerome de Seze, Xavier Montalban, Krzysztof Selmaj, Heinz Wiendl, Stephen C Reingold, Garry R Cutter, Thomas Doerner, Hans-Peter Hartung, Per Soelberg Sørensen, Israel Steiner, Jerry S Wolinsky, Carlos Ballario, Christian Calvo Vildoso, Jorge Gustavo Jose, Norma Haydee Deri, Susana Liwacki, Jeannette Lechner-Scott, John Parratt, Suzanne Hodgkinson, Eva-Maria Maida, Fritz Leutmezer, Barbara Willekens, Bart Van Wijmeersch, Guy Laureys, Jo Caekebeke, Karine Geens, Ludo Vanopdenbosch, Olivier Deryck, Valerie Delvaux, Vincent Van Pesch, Ivan Milanov, Ivaylo Tarnev, Lyubomir Haralanov, Maria Manova Slavova, Penko Shotekov, Francois Emond, Francois Grandmaison, Francois Jacques, Liesly Lee, Marie Sarah Gagne Brosseau, Mark Freedman, Martin Cloutier, Robert Carruthers, Sarah Morrow, Yves Lapierre, Anton Vladic, Hana Bokun, Igor Antoncic, Marija Bosnjak Pasic, Mario Habek, Silva Butkovic Soldo, Vladimira Vuletic, Alena Martinkova, Eva Meluzinova, Ivana Stetkarova, Jan Mares, Jolana Markova, Marta Vachova, Martin Valis, Michaela Tyblova, Michal Dufek, Ondrej Skoda, Pavel Hradilek, Ana Voldsgaard Jensen, Helle Hvilsted Nielsen, Kristina Svendsen, Mads Ravnborg, Peter Vestergaard Rasmussen, Katrin Gross-Paju, Sulev Haldre, Juha Pekka Eralinna, Marja-Liisa Sumelahti, Bruno Brochet, Celine Louapre, Christine Lebrun-Frenay, David Axel Laplaud, Gilles Edan, Giovanni Castelnovo, Marc Debouverie, Patrick Vermersch, Pierre Clavelou, Pierre Labauge, Achim Berthele, Aiden Haghikia, Anselm Kornhuber, Arnfin Bergmann, Benedikt Frank, Birte Elias-Hamp, Bjoern Tackenberg, Brigitte Wildemann, Erik Strauss, Eugen Schlegel, Florian Then Bergh, Gereon Nelles, Hayrettin Tumani, Karl-Otto Sigel, Martin Stangel, Matthias Boehringer, Olaf Martin Hoffmann, Patrick Oschmann, Reinhard Hohlfeld, Silke Walter, Sylvia Menck, Till Sprenger, Tjalf Ziemssen, Veit Ulrich Becker, Vera Straeten, Konstantinos Kilidireas, Konstantinos Voumvourakis, Nikolaos Fakas, Nikolaos Grigoriadis, Agnes Koves, Csilla Rozsa, Krisztina Kovacs, Laszlo Vecsei, Satori Maria, Zita Biro, Anshu Rohatgi, Dheeraj Khurana, Jeyaraj Durai Pandian, Joy Dev Mukherji, Lekha Pandit, Meena Angamuthu Kanikannan, Pahari Ghosh, Rahul Chakor, Rahul Kulkarni, Roopkumar Gursahani, Sangeeta Ravat, Srinivasa Rangasetty, Suresh Kumar, Alla Shifrin, Arnon Karni, Radi Shahien, Ron Milo, Antonio Uccelli, Carlo Pozzilli, Francesco Sacca, Giacomo Lus, Girolama Alessandra Marfia, Laura Brambilla, Marco Salvetti, Massimo Filippi, Mauro Zaffaroni, Paolo Gallo, Silvia Rossi, Simona Bonavita, Valeria Studer, Andrejs Millers, Guntis Karelis, Jolanta Kalnina, Dalia Mickeviciene, Rasa Kizlaitiene, Angelica Carbajal Ramirez, Juan Jose Lopez Prieto, Beatrijs Wokke, Bob W Van Oosten, Peter Van Domburg, Raymond Hupperts, Rogier Q Hintzen, Astrid Edland, Cesar Castaneda, Julio Perez, Martin Gavidia, Andrzej Wiak, Bartosz Karaszewski, Elzbieta Jasinska, Halina Bartosik Psujek, Iwona Jastrzebska, Jaroslaw Slawek, Maciej Maciejowski, Miroslaw Dziki, Monika Adamczyk Sowa, Robert Bonek, Waldemar Fryze, Ana Martins Da Silva, Angela Timoteo, Antonio Vasco Salgado, Carlos Capela, Carlos Veira, Filipe Correia, Joao Cerqueira, Joao De Sa, Livia De Sousa, Raquel Gouveia, Alina Sergeevna Agafina, Anna Naumovna Belova, Denis Viktorovich Sazonov, Dmitry Pokhabov, Ekaterina Igorevna Kairbekova, Elena Gennadievna Arefieva, Farit Axatovich Khabirov, Igor Vyacheslavovich Litvinenko, Igor Stolyarov, Irina Aleksandrovna Sokolova, Larisa Ivanovna Volkova, Maria Vafaevna Davydovskaya, Maria Nikolaevna Zaharova, Nadezhda Alekseevna Malkova, Natalia Agafonovna Totolyan, Nikolay Vasilievich Dorogov, Stella Anatolievna Sivertseva, Egon Kurca, Georgi Krastev, Miroslav Brozman, Peter Koleda, Peter Turcani, Peter Valkovic, Viera Hancinova, Vladimir Donath, Chris Retief, Michael Isaacs, Albert Saiz Hinarejos, Alfredo Rodriguez Antigüedad, Bonaventura Casanova Estruch, Celia Oreja-Guevara, Gemma Reig Rosello, Jose Carlos Alvarez Cermeño, Jose Martinez Rodriguez, Jose Meca Lallana, Juan Antonio Garcia Merino, Lucia Forero Diaz, Lucienne Costa Frossard Franca, Luis Querol Gutierrez, Lluis Ramio Torrenta, Pedro Serrano Castro, Rafael Arroyo Gonzalez, Sara Eichau Madueño, Sergio Martinez Yelamos, Tamara Castillo Trivino, Virgina Meca Lallana, Xaviere Montalban Gairin, Fredrik Piehl, Jan Lycke, Chiara Zecca, Tobias Derfuss, Thy-Sheng Lin, Somsak Tiamkao, Ayse Nur Yuceyar, Aysun Soysal, Belgin Petek Balci, Cavit Boz, Husnu Efendi, Murat Terzi, Serhan Sevim, Serkan Ozakbas, Andrew Gale, Ben Turner, David Barnes, David Paling, Eli Silber, James Overell, Matthew Craner, Aaron Carlson, Adam Wolff, Adaeze Onuoha, Adnan Subei, Ahmad Ata, Aimee Borazanci, Akram Dastagir, Alberto Vasquez, Alison Brooke Allen, Andrew P Keegan, Angel Carrasco, Angel R Chinea Martinez, Ann Bass, Annette Okai, April Erwin, Ariel Antezana-Antezana, Barbara Green, Bharathy E Sundaram, Bhupendra Khatri, Bhupesh Dihenia, Bogdan Gheorghiu, Brian Costell, Brian Steingo, Bruce L Hughes, Carrie M Hersh, Christopher Laganke, Christopher Luzzio, Corey Ford, Craig Edward Herrman, Craig Senzon, Cynthia Huffman, Daniel R Wynn, David D O Bear, David Lesch, David H Mattson, David Weisman, Deborah A Burke, Dennis W Dietrich, Deren Huang, Derrick Robertson, Djamchid Lotfi, Don Joseph Alfonso, Dusan Stefoski, Edward J Fox, Emily Pharr, Enrique Alvarez, Evanthia Bernitsas, Faria Amjad, Gabriel Pardo, Geoffrey Eubank, Gerald Mcintosh, Giles F Crowell, Hemanth Rao, J Michael Hemphill, Jack H Florin, Jacqueline Nicholas, James Napier, James Scott, Jason M Silversteen, Javier Vasallo, Jean-Raphael Schneider, Jeanette Wendt, Jeffrey Cohen, Jeffrey Gross, Jeffrey Groves, Jeffrey Kaplan, Jessica Stulc, Joanna A Cooper, John Foley, John Scagnelli, Jonathan C Calkwood, Jose Pizarro Otero, Jose Rafecas, Joshua Katz, Juliette S Saad, Katherine Standley, Keith Edwards, Kenneth Sharlin, Khurram Bashir, Kimberly Wagner, Kore Liow, Larry Lee Blankenship Jr, Laszlo Mate, Liliana Montoya, Lon D Lynn, Mark Agius, Mark Cascione, Mark Allan Goldstein, Mark Janicki, Martin R Bialow, Mary Denise Hughes, Matthew J Baker, Michelle Apperson, Michelle B Kuczma, M Mateo Paz Soldan, Mirela Cerghet, Nathaniel Robb Whaley, Paul K Winner, Pavle Repovic, Praful Kelkar, Romero Rekha Pillai, Ricardo Ayala, Richard Sater, Randall Trudell, Robert Fairborn Armstrong, Robert Thomas Nahouraii, Robert Naismith, Ronald S Murray, Samuel Hunter, Sara Qureshi, Sharon Lynch, Sibyl Wray, Silvia R Delgado, Stacy Donlon, Stanley Cohan, Stanya Smith, Stuart James Shafer, Susan Azalone, Susan Hibbs, Tamara A Miller, Thomas Giancarlo, Troy Desai, Varun K Saxena, Virginia Simnad, William David Honeycutt, William Logan, William E McElveen, William Wagner, University of California [San Francisco] (UCSF), University of California, Perelman School of Medicine, University of Pennsylvania [Philadelphia], Cleveland Clinic, IRCCS Ospedale San Raffaele [Milan, Italy], Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia [Buenos Aires] (FLENI), FLENI, Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Washington University School of Medicine in St. Louis, Washington University in Saint Louis (WUSTL), CIC Strasbourg (Centre d’Investigation Clinique Plurithématique (CIC - P) ), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Strasbourg (UNISTRA)-Hôpital de Hautepierre [Strasbourg]-Nouvel Hôpital Civil de Strasbourg, University Hospital Basel [Basel], Vall d'Hebron University Hospital [Barcelona], University of Warmia and Mazury [Olsztyn], University of Münster, Novartis Pharma S.A.S., Novartis Pharmaceuticals, University of Basel (Unibas), Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), Université de Montpellier (UM), Willekens, Barbara, ASCLEPIOS I and ASCLEPIOS II Trial Groups, Hauser, S. L., Bar-Or, A., Cohen, J. A., Comi, G., Correale, J., Coyle, P. K., Cross, A. H., de Seze, J., Leppert, D., Montalban, X., Selmaj, K., Wiendl, H., Kerloeguen, C., Willi, R., Li, B., Kakarieka, A., Tomic, D., Goodyear, A., Pingili, R., Haring, D. A., Ramanathan, K., Merschhemke, M., Kappos, L., Asclepios, I and ASCLEPIOS II Trial Group, Filippi, M, L Hauser, Stephen, Kappos, Ludwig, Bar-Or, Amit, A Cohen, Jeffrey, Comi, Giancarlo, Correale, Jorge, K Coyle, Patricia, Cross, Anne, de Seze, Jerome, Montalban, Xavier, Selmaj, Krzysztof, Wiendl, Heinz, C Reingold, Stephen, R Cutter, Garry, Doerner, Thoma, Hartung, Hans-Peter, Soelberg Sørensen, Per, Steiner, Israel, S Wolinsky, Jerry, Ballario, Carlo, Calvo Vildoso, Christian, Gustavo Jose, Jorge, Haydee Deri, Norma, Liwacki, Susana, Lechner-Scott, Jeannette, Parratt, John, Hodgkinson, Suzanne, Maida, Eva-Maria, Leutmezer, Fritz, Van Wijmeersch, Bart, Laureys, Guy, Caekebeke, Jo, Geens, Karine, Vanopdenbosch, Ludo, Deryck, Olivier, Delvaux, Valerie, Van Pesch, Vincent, Milanov, Ivan, Tarnev, Ivaylo, Haralanov, Lyubomir, Manova Slavova, Maria, Shotekov, Penko, Emond, Francoi, Grandmaison, Francoi, Jacques, Francoi, Lee, Liesly, Sarah Gagne Brosseau, Marie, Freedman, Mark, Cloutier, Martin, Carruthers, Robert, Morrow, Sarah, Lapierre, Yve, Vladic, Anton, Bokun, Hana, Antoncic, Igor, Bosnjak Pasic, Marija, Habek, Mario, Butkovic Soldo, Silva, Vuletic, Vladimira, Martinkova, Alena, Meluzinova, Eva, Stetkarova, Ivana, Mares, Jan, Markova, Jolana, Vachova, Marta, Valis, Martin, Tyblova, Michaela, Dufek, Michal, Skoda, Ondrej, Hradilek, Pavel, Voldsgaard Jensen, Ana, Hvilsted Nielsen, Helle, Svendsen, Kristina, Ravnborg, Mad, Vestergaard Rasmussen, Peter, Gross-Paju, Katrin, Haldre, Sulev, Pekka Eralinna, Juha, Sumelahti, Marja-Liisa, Brochet, Bruno, Louapre, Celine, Lebrun-Frenay, Christine, Axel Laplaud, David, Edan, Gille, Castelnovo, Giovanni, Debouverie, Marc, Vermersch, Patrick, Clavelou, Pierre, Labauge, Pierre, Berthele, Achim, Haghikia, Aiden, Kornhuber, Anselm, Bergmann, Arnfin, Frank, Benedikt, Elias-Hamp, Birte, Tackenberg, Bjoern, Wildemann, Brigitte, Strauss, Erik, Schlegel, Eugen, Then Bergh, Florian, Nelles, Gereon, Tumani, Hayrettin, Sigel, Karl-Otto, Stangel, Martin, Boehringer, Matthia, Martin Hoffmann, Olaf, Oschmann, Patrick, Hohlfeld, Reinhard, Walter, Silke, Menck, Sylvia, Sprenger, Till, Ziemssen, Tjalf, Ulrich Becker, Veit, Straeten, Vera, Kilidireas, Konstantino, Voumvourakis, Konstantino, Fakas, Nikolao, Grigoriadis, Nikolao, Koves, Agne, Rozsa, Csilla, Kovacs, Krisztina, Vecsei, Laszlo, Maria, Satori, Biro, Zita, Rohatgi, Anshu, Khurana, Dheeraj, Durai Pandian, Jeyaraj, Dev Mukherji, Joy, Pandit, Lekha, Angamuthu Kanikannan, Meena, Ghosh, Pahari, Chakor, Rahul, Kulkarni, Rahul, Gursahani, Roopkumar, Ravat, Sangeeta, Rangasetty, Srinivasa, Kumar, Suresh, Shifrin, Alla, Karni, Arnon, Shahien, Radi, Milo, Ron, Uccelli, Antonio, Pozzilli, Carlo, Sacca, Francesco, Lus, Giacomo, Alessandra Marfia, Girolama, Brambilla, Laura, Salvetti, Marco, Filippi, Massimo, Zaffaroni, Mauro, Gallo, Paolo, Rossi, Silvia, Bonavita, Simona, Studer, Valeria, Millers, Andrej, Karelis, Gunti, Kalnina, Jolanta, Mickeviciene, Dalia, Kizlaitiene, Rasa, Carbajal Ramirez, Angelica, Jose Lopez Prieto, Juan, Wokke, Beatrij, W Van Oosten, Bob, Van Domburg, Peter, Hupperts, Raymond, Q Hintzen, Rogier, Edland, Astrid, Castaneda, Cesar, Perez, Julio, Gavidia, Martin, Wiak, Andrzej, Karaszewski, Bartosz, Jasinska, Elzbieta, Bartosik Psujek, Halina, Jastrzebska, Iwona, Slawek, Jaroslaw, Maciejowski, Maciej, Dziki, Miroslaw, Adamczyk Sowa, Monika, Bonek, Robert, Fryze, Waldemar, Martins Da Silva, Ana, Timoteo, Angela, Vasco Salgado, Antonio, Capela, Carlo, Veira, Carlo, Correia, Filipe, Cerqueira, Joao, De Sa, Joao, De Sousa, Livia, Gouveia, Raquel, Sergeevna Agafina, Alina, Naumovna Belova, Anna, Viktorovich Sazonov, Deni, Pokhabov, Dmitry, Igorevna Kairbekova, Ekaterina, Gennadievna Arefieva, Elena, Axatovich Khabirov, Farit, Vyacheslavovich Litvinenko, Igor, Stolyarov, Igor, Aleksandrovna Sokolova, Irina, Ivanovna Volkova, Larisa, Vafaevna Davydovskaya, Maria, Nikolaevna Zaharova, Maria, Alekseevna Malkova, Nadezhda, Agafonovna Totolyan, Natalia, Vasilievich Dorogov, Nikolay, Anatolievna Sivertseva, Stella, Kurca, Egon, Krastev, Georgi, Brozman, Miroslav, Koleda, Peter, Turcani, Peter, Valkovic, Peter, Hancinova, Viera, Donath, Vladimir, Retief, Chri, Isaacs, Michael, Saiz Hinarejos, Albert, Rodriguez Antigüedad, Alfredo, Casanova Estruch, Bonaventura, Oreja-Guevara, Celia, Reig Rosello, Gemma, Carlos Alvarez Cermeño, Jose, Martinez Rodriguez, Jose, Meca Lallana, Jose, Antonio Garcia Merino, Juan, Forero Diaz, Lucia, Costa Frossard Franca, Lucienne, Querol Gutierrez, Lui, Ramio Torrenta, Llui, Serrano Castro, Pedro, Arroyo Gonzalez, Rafael, Eichau Madueño, Sara, Martinez Yelamos, Sergio, Castillo Trivino, Tamara, Meca Lallana, Virgina, Montalban Gairin, Xaviere, Piehl, Fredrik, Lycke, Jan, Zecca, Chiara, Derfuss, Tobia, Lin, Thy-Sheng, Tiamkao, Somsak, Nur Yuceyar, Ayse, Soysal, Aysun, Petek Balci, Belgin, Boz, Cavit, Efendi, Husnu, Terzi, Murat, Sevim, Serhan, Ozakbas, Serkan, Gale, Andrew, Turner, Ben, Barnes, David, Paling, David, Silber, Eli, Overell, Jame, Craner, Matthew, Carlson, Aaron, Wolff, Adam, Onuoha, Adaeze, Subei, Adnan, Ata, Ahmad, Borazanci, Aimee, Dastagir, Akram, Vasquez, Alberto, Brooke Allen, Alison, P Keegan, Andrew, Carrasco, Angel, R Chinea Martinez, Angel, Bass, Ann, Okai, Annette, Erwin, April, Antezana-Antezana, Ariel, Green, Barbara, E Sundaram, Bharathy, Khatri, Bhupendra, Dihenia, Bhupesh, Gheorghiu, Bogdan, Costell, Brian, Steingo, Brian, L Hughes, Bruce, M Hersh, Carrie, Laganke, Christopher, Luzzio, Christopher, Ford, Corey, Edward Herrman, Craig, Senzon, Craig, Huffman, Cynthia, R Wynn, Daniel, O Bear, David D, Lesch, David, H Mattson, David, Weisman, David, A Burke, Deborah, W Dietrich, Denni, Huang, Deren, Robertson, Derrick, Lotfi, Djamchid, Joseph Alfonso, Don, Stefoski, Dusan, J Fox, Edward, Pharr, Emily, Alvarez, Enrique, Bernitsas, Evanthia, Amjad, Faria, Pardo, Gabriel, Eubank, Geoffrey, Mcintosh, Gerald, F Crowell, Gile, Rao, Hemanth, Michael Hemphill, J, H Florin, Jack, Nicholas, Jacqueline, Napier, Jame, Scott, Jame, M Silversteen, Jason, Vasallo, Javier, Schneider, Jean-Raphael, Wendt, Jeanette, Cohen, Jeffrey, Gross, Jeffrey, Groves, Jeffrey, Kaplan, Jeffrey, Stulc, Jessica, A Cooper, Joanna, Foley, John, Scagnelli, John, C Calkwood, Jonathan, Pizarro Otero, Jose, Rafecas, Jose, Katz, Joshua, S Saad, Juliette, Standley, Katherine, Edwards, Keith, Sharlin, Kenneth, Bashir, Khurram, Wagner, Kimberly, Liow, Kore, Lee Blankenship Jr, Larry, Mate, Laszlo, Montoya, Liliana, D Lynn, Lon, Agius, Mark, Cascione, Mark, Allan Goldstein, Mark, Janicki, Mark, R Bialow, Martin, Denise Hughes, Mary, J Baker, Matthew, Apperson, Michelle, B Kuczma, Michelle, Mateo Paz Soldan, M, Cerghet, Mirela, Robb Whaley, Nathaniel, K Winner, Paul, Repovic, Pavle, Kelkar, Praful, Rekha Pillai, Romero, Ayala, Ricardo, Sater, Richard, Trudell, Randall, Fairborn Armstrong, Robert, Thomas Nahouraii, Robert, Naismith, Robert, S Murray, Ronald, Hunter, Samuel, Qureshi, Sara, Lynch, Sharon, Wray, Sibyl, R Delgado, Silvia, Donlon, Stacy, Cohan, Stanley, Smith, Stanya, James Shafer, Stuart, Azalone, Susan, Hibbs, Susan, A Miller, Tamara, Giancarlo, Thoma, Desai, Troy, K Saxena, Varun, Simnad, Virginia, David Honeycutt, William, Logan, William, E McElveen, William, Wagner, William, Stephen, L Hauser, Ludwig, Kappo, Amit, Bar-Or, Jeffrey, A Cohen, Giancarlo, Comi, Jorge, Correale, Patricia, K Coyle, Anne, Cro, Jerome de Seze, Xavier, Montalban, Krzysztof, Selmaj, Heinz, Wiendl, Stephen, C Reingold, Garry, R Cutter, Thomas, Doerner, Hans-Peter, Hartung, Per Soelberg Sørensen, Israel, Steiner, Jerry, S Wolinsky, Carlos, Ballario, Christian Calvo Vildoso, Jorge Gustavo Jose, Norma Haydee Deri, Susana, Liwacki, Jeannette, Lechner-Scott, John, Parratt, Suzanne, Hodgkinson, Eva-Maria, Maida, Fritz, Leutmezer, Barbara, Willeken, Bart Van Wijmeersch, Guy, Laurey, Karine, Geen, Ludo, Vanopdenbosch, Olivier, Deryck, Valerie, Delvaux, Vincent Van Pesch, Ivan, Milanov, Ivaylo, Tarnev, Lyubomir, Haralanov, Maria Manova Slavova, Penko, Shotekov, Francois, Emond, Francois, Grandmaison, Francois, Jacque, Liesly, Lee, Marie Sarah Gagne Brosseau, Mark, Freedman, Martin, Cloutier, Robert, Carruther, Sarah, Morrow, Yves, Lapierre, Anton, Vladic, Hana, Bokun, Igor, Antoncic, Marija Bosnjak Pasic, Mario, Habek, Silva Butkovic Soldo, Vladimira, Vuletic, Alena, Martinkova, Eva, Meluzinova, Ivana, Stetkarova, Jan, Mare, Jolana, Markova, Marta, Vachova, Martin, Vali, Michaela, Tyblova, Michal, Dufek, Ondrej, Skoda, Pavel, Hradilek, Ana Voldsgaard Jensen, Helle Hvilsted Nielsen, Kristina, Svendsen, Mads, Ravnborg, Peter Vestergaard Rasmussen, Katrin, Gross-Paju, Sulev, Haldre, Juha Pekka Eralinna, Marja-Liisa, Sumelahti, Bruno, Brochet, Celine, Louapre, Christine, Lebrun-Frenay, David Axel Laplaud, Gilles, Edan, Giovanni, Castelnovo, Marc, Debouverie, Patrick, Vermersch, Pierre, Clavelou, Pierre, Labauge, Achim, Berthele, Aiden, Haghikia, Anselm, Kornhuber, Arnfin, Bergmann, Benedikt, Frank, Birte, Elias-Hamp, Bjoern, Tackenberg, Brigitte, Wildemann, Erik, Strau, Eugen, Schlegel, Florian Then Bergh, Gereon, Nelle, Hayrettin, Tumani, Karl-Otto, Sigel, Martin, Stangel, Matthias, Boehringer, Olaf Martin Hoffmann, Patrick, Oschmann, Reinhard, Hohlfeld, Silke, Walter, Sylvia, Menck, Till, Sprenger, Tjalf, Ziemssen, Veit Ulrich Becker, Vera, Straeten, Konstantinos, Kilidirea, Konstantinos, Voumvouraki, Nikolaos, Faka, Nikolaos, Grigoriadi, Agnes, Kove, Csilla, Rozsa, Krisztina, Kovac, Laszlo, Vecsei, Satori, Maria, Zita, Biro, Anshu, Rohatgi, Dheeraj, Khurana, Jeyaraj Durai Pandian, Joy Dev Mukherji, Lekha, Pandit, Meena Angamuthu Kanikannan, Pahari, Ghosh, Rahul, Chakor, Rahul, Kulkarni, Roopkumar, Gursahani, Sangeeta, Ravat, Srinivasa, Rangasetty, Suresh, Kumar, Alla, Shifrin, Arnon, Karni, Radi, Shahien, Ron, Milo, Antonio, Uccelli, Carlo, Pozzilli, Sacca', Francesco, Giacomo, Lu, Girolama Alessandra Marfia, Laura, Brambilla, Marco, Salvetti, Massimo, Filippi, Mauro, Zaffaroni, Paolo, Gallo, Silvia, Rossi, Simona, Bonavita, Valeria, Studer, Andrejs, Miller, Guntis, Kareli, Jolanta, Kalnina, Dalia, Mickeviciene, Rasa, Kizlaitiene, Angelica Carbajal Ramirez, Juan Jose Lopez Prieto, Beatrijs, Wokke, Bob, W Van Oosten, Peter Van Domburg, Raymond, Huppert, Rogier, Q Hintzen, Astrid, Edland, Cesar, Castaneda, Julio, Perez, Martin, Gavidia, Andrzej, Wiak, Bartosz, Karaszewski, Elzbieta, Jasinska, Halina Bartosik Psujek, Iwona, Jastrzebska, Jaroslaw, Slawek, Maciej, Maciejowski, Miroslaw, Dziki, Monika Adamczyk Sowa, Robert, Bonek, Waldemar, Fryze, Ana Martins Da Silva, Angela, Timoteo, Antonio Vasco Salgado, Carlos, Capela, Carlos, Veira, Filipe, Correia, Joao, Cerqueira, Joao De Sa, Livia De Sousa, Raquel, Gouveia, Alina Sergeevna Agafina, Anna Naumovna Belova, Denis Viktorovich Sazonov, Dmitry, Pokhabov, Ekaterina Igorevna Kairbekova, Elena Gennadievna Arefieva, Farit Axatovich Khabirov, Igor Vyacheslavovich Litvinenko, Igor, Stolyarov, Irina Aleksandrovna Sokolova, Larisa Ivanovna Volkova, Maria Vafaevna Davydovskaya, Maria Nikolaevna Zaharova, Nadezhda Alekseevna Malkova, Natalia Agafonovna Totolyan, Nikolay Vasilievich Dorogov, Stella Anatolievna Sivertseva, Egon, Kurca, Georgi, Krastev, Miroslav, Brozman, Peter, Koleda, Peter, Turcani, Peter, Valkovic, Viera, Hancinova, Vladimir, Donath, Chris, Retief, Michael, Isaac, Albert Saiz Hinarejos, Alfredo Rodriguez Antigüedad, Bonaventura Casanova Estruch, Celia, Oreja-Guevara, Gemma Reig Rosello, Jose Carlos Alvarez Cermeño, Jose Martinez Rodriguez, Jose Meca Lallana, Juan Antonio Garcia Merino, Lucia Forero Diaz, Lucienne Costa Frossard Franca, Luis Querol Gutierrez, Lluis Ramio Torrenta, Pedro Serrano Castro, Rafael Arroyo Gonzalez, Sara Eichau Madueño, Sergio Martinez Yelamos, Tamara Castillo Trivino, Virgina Meca Lallana, Xaviere Montalban Gairin, Fredrik, Piehl, Jan, Lycke, Chiara, Zecca, Tobias, Derfu, Thy-Sheng, Lin, Somsak, Tiamkao, Ayse Nur Yuceyar, Aysun, Soysal, Belgin Petek Balci, Cavit, Boz, Husnu, Efendi, Murat, Terzi, Serhan, Sevim, Serkan, Ozakba, Andrew, Gale, Ben, Turner, David, Barne, David, Paling, Eli, Silber, James, Overell, Matthew, Craner, Aaron, Carlson, Adam, Wolff, Adaeze, Onuoha, Adnan, Subei, Ahmad, Ata, Aimee, Borazanci, Akram, Dastagir, Alberto, Vasquez, Alison Brooke Allen, Andrew, P Keegan, Angel, Carrasco, Angel, R Chinea Martinez, Ann, Ba, Annette, Okai, April, Erwin, Ariel, Antezana-Antezana, Barbara, Green, Bharathy, E Sundaram, Bhupendra, Khatri, Bhupesh, Dihenia, Bogdan, Gheorghiu, Brian, Costell, Brian, Steingo, Bruce, L Hughe, Carrie, M Hersh, Christopher, Laganke, Christopher, Luzzio, Corey, Ford, Craig Edward Herrman, Craig, Senzon, Cynthia, Huffman, Daniel, R Wynn, David D, O Bear, David, Lesch, David, H Mattson, David, Weisman, Deborah, A Burke, Dennis, W Dietrich, Deren, Huang, Derrick, Robertson, Djamchid, Lotfi, Don Joseph Alfonso, Dusan, Stefoski, Edward, J Fox, Emily, Pharr, Enrique, Alvarez, Evanthia, Bernitsa, Faria, Amjad, Gabriel, Pardo, Geoffrey, Eubank, Gerald, Mcintosh, Giles, F Crowell, Hemanth, Rao, J Michael Hemphill, Jack, H Florin, Jacqueline, Nichola, James, Napier, James, Scott, Jason, M Silversteen, Javier, Vasallo, Jean-Raphael, Schneider, Jeanette, Wendt, Jeffrey, Cohen, Jeffrey, Gro, Jeffrey, Grove, Jeffrey, Kaplan, Jessica, Stulc, Joanna, A Cooper, John, Foley, John, Scagnelli, Jonathan, C Calkwood, Jose Pizarro Otero, Jose, Rafeca, Joshua, Katz, Juliette, S Saad, Katherine, Standley, Keith, Edward, Kenneth, Sharlin, Khurram, Bashir, Kimberly, Wagner, Kore, Liow, Larry Lee Blankenship Jr, Laszlo, Mate, Liliana, Montoya, Lon, D Lynn, Mark, Agiu, Mark, Cascione, Mark Allan Goldstein, Mark, Janicki, Martin, R Bialow, Mary Denise Hughes, Matthew, J Baker, Michelle, Apperson, Michelle, B Kuczma, M Mateo Paz Soldan, Mirela, Cerghet, Nathaniel Robb Whaley, Paul, K Winner, Pavle, Repovic, Praful, Kelkar, Romero Rekha Pillai, Ricardo, Ayala, Richard, Sater, Randall, Trudell, Robert Fairborn Armstrong, Robert Thomas Nahouraii, Robert, Naismith, Ronald, S Murray, Samuel, Hunter, Sara, Qureshi, Sharon, Lynch, Sibyl, Wray, Silvia, R Delgado, Stacy, Donlon, Stanley, Cohan, Stanya, Smith, Stuart James Shafer, Susan, Azalone, Susan, Hibb, Tamara, A Miller, Thomas, Giancarlo, Troy, Desai, Varun, K Saxena, Virginia, Simnad, William David Honeycutt, William, Logan, William, E McElveen, William, Wagner, University of California [San Francisco] (UC San Francisco), University of California (UC), University of Pennsylvania, Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Nouvel Hôpital Civil de Strasbourg-Hôpital de Hautepierre [Strasbourg], Westfälische Wilhelms-Universität Münster = University of Münster (WWU), Herrada, Anthony, and UCL - SSS/IONS/CEMO - Pôle Cellulaire et moléculaire

Subjects
Male, MESH: Multiple Sclerosis, Relapsing-Remitting, T-Lymphocytes, Hydroxybutyrates, Kaplan-Meier Estimate, 030204 cardiovascular system & hematology, Pharmacology, Relapsing-Remitting, MESH: Magnetic Resonance Imaging, chemistry.chemical_compound, 0302 clinical medicine, Teriflunomide, Monoclonal, MESH: Double-Blind Method, 030212 general & internal medicine, Humanized, MESH: Toluidines, B-Lymphocytes, [SDV.MHEP] Life Sciences [q-bio]/Human health and pathology, biology, Subcutaneous, B-Lymphocyte, Brain, General Medicine, Magnetic Resonance Imaging, MESH: Crotonates, Crotonates, Pyrimidine metabolism, Disease Progression, Female, MESH: Disease Progression, Antibody, Human, Adult, Multiple Sclerosis, Toluidines, medicine.drug_class, Injections, Subcutaneous, Injections, Subcutaneou, Monoclonal antibody, Ofatumumab, Settore MED/26, Antibodies, Monoclonal, Humanized, Crotonate, Antibodies, Injections, 03 medical and health sciences, MESH: Brain, Multiple Sclerosis, Relapsing-Remitting, Double-Blind Method, MESH: B-Lymphocytes, Nitriles, medicine, Humans, MESH: Kaplan-Meier Estimate, MESH: Humans, business.industry, Multiple sclerosis, MESH: Injections, Subcutaneous, MESH: Adult, medicine.disease, MESH: Male, MESH: T-Lymphocytes, T-Lymphocyte, Multicenter study, chemistry, MESH: Antibodies, Monoclonal, Humanized, biology.protein, Human medicine, business, MESH: Female, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; Background: Ofatumumab, a subcutaneous anti-CD20 monoclonal antibody, selectively depletes B cells. Teriflunomide, an oral inhibitor of pyrimidine synthesis, reduces T-cell and B-cell activation. The relative effects of these two drugs in patients with multiple sclerosis are not known.Methods: In two double-blind, double-dummy, phase 3 trials, we randomly assigned patients with relapsing multiple sclerosis to receive subcutaneous ofatumumab (20 mg every 4 weeks after 20-mg loading doses at days 1, 7, and 14) or oral teriflunomide (14 mg daily) for up to 30 months. The primary end point was the annualized relapse rate. Secondary end points included disability worsening confirmed at 3 months or 6 months, disability improvement confirmed at 6 months, the number of gadolinium-enhancing lesions per T1-weighted magnetic resonance imaging (MRI) scan, the annualized rate of new or enlarging lesions on T2-weighted MRI, serum neurofilament light chain levels at month 3, and change in brain volume.Results: Overall, 946 patients were assigned to receive ofatumumab and 936 to receive teriflunomide; the median follow-up was 1.6 years. The annualized relapse rates in the ofatumumab and teriflunomide groups were 0.11 and 0.22, respectively, in trial 1 (difference, -0.11; 95% confidence interval [CI], -0.16 to -0.06; P

Published
2020
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46. The Low-Temperature Oxidation of Propane by using H2O2and Fe/ZSM-5 Catalysts: Insights into the Active Site and Enhancement of Catalytic Turnover Frequencies

Author

Virginie Peneau, Robert Leyshon Jenkins, Greg Shaw, Stefan Peitz, Stuart Hamilton Taylor, Robert Armstrong, Graham J. Hutchings, Zanthoff Horst-Werner, Nikolaos Dimitratos, Jun Xu, Christopher J. Kiely, David J. Morgan, Qian He, Guido Stochniol, Peneau, Virginie, Armstrong, Robert D., Shaw, Greg, Xu, Jun, Jenkins, Robert L., Morgan, David J., Dimitratos, Nikolao, Taylor, Stuart H., Zanthoff, Horst W., Peitz, Stefan, Stochniol, Guido, He, Qian, Kiely, Christopher J., and Hutchings, Graham J.

Subjects
Inorganic chemistry, Iron oxide, 010402 general chemistry, 01 natural sciences, Catalysis, Catalysi, Inorganic Chemistry, chemistry.chemical_compound, Propane, QD, Partial oxidation, Physical and Theoretical Chemistry, Zeolite, propane oxidation, Alkane, chemistry.chemical_classification, Aqueous solution, 010405 organic chemistry, Organic Chemistry, selective oxidation, 0104 chemical sciences, natural ga, chemistry, ZSM-5, zeolite catalyst
Abstract

Fe-containing ZSM-5 catalysts are reported to be efficient catalysts for the partial oxidation of propane to oxygenated products at reaction temperatures as low as 50 °C in an aqueous phase reaction when using the green oxidant H2O2. It was previously proposed that extra framework Fe species at the exchange sites of the zeolite are responsible for activation of both the alkane and hydrogen peroxide. Through a systematic study of the influence of framework topology and exchange properties, it is now shown that this high catalytic activity is specific to the MFI-type Brønsted acidic zeolite ZSM-5. Furthermore, through a simple aqueous acid washing treatment, leaching of approximately 77 % of iron present within a Fe/ZSM-5 catalyst only caused the relative propane conversion to decrease by 17 %; implying that most of the initially loaded Fe does not actually contribute to the catalytic activity. This small change in conversion after ‘excess’ Fe removal, amounts to a three-fold increase in turnover frequency (TOF) (Fe) from 66 h−1 to 232 h−1 compared with the parent Fe/ZSM-5 catalyst. By comparing these samples, it is shown by NH3 temperature-programmed desorption, 27Al magic angle spinning NMR spectroscopy, X-ray photoelectron spectroscopy and TEM analysis that surface iron oxide species are effectively spectators in the oxidation of propane with H2O2. This provides further insight as to the location and true nature of the catalytically active Fe species.

Published
2017
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47. Low temperature selective oxidation of methane to methanol using titania supported gold palladium copper catalysts

Author

Jose Antonio Lopez-Sanchez, Robert Armstrong, David J. Morgan, Robert Leyshon Jenkins, Stuart Hamilton Taylor, Graham J. Hutchings, Michael M. Forde, Nikolaos Dimitratos, Ceri Hammond, Mohd Hasbi Ab. Rahim, Simon J. Freakley, G. Lalev, Ab Rahim, Mohd Hasbi, Armstrong, Robert D., Hammond, Ceri, Dimitratos, Nikolao, Freakley, Simon J., Forde, Michael M., Morgan, David J., Lalev, Georgi, Jenkins, Robert L., Lopez-Sanchez, Jose Antonio, Taylor, Stuart H., and Hutchings, Graham J.

Subjects
010405 organic chemistry, Inorganic chemistry, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Copper, Methane, Catalysis, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Methanol, Selectivity, Bimetallic strip, Incipient wetness impregnation, Palladium
Abstract

The selective oxidation of methane to methanol has been studied using trimetallic AuPdCu/TiO2 catalysts prepared by incipient wetness impregnation. They are able to catalyse the selective oxidation of methane to methanol under mild aqueous reaction conditions using H2O2 as the oxidant. When compared with bimetallic, Au-Pd/TiO2 analogues, the new trimetallic catalysts present productivities which are up to 5 times greater under the same test conditions, and this is coupled with methanol selectivity of up to 83 %. Characterisation shows that whilst Au-Pd is present as Au- core Pd- shell nanoparticles, copper is present as either Cu or Cu2O in < 5 nm particles.

Published
2016

48. The partial oxidation of propane under mild aqueous conditions with H2O2 and ZSM-5 catalysts

Author

Robert Leyshon Jenkins, Zanthoff Horst-Werner, Stefan Pietz, Nikolaos Dimitratos, Virginie Peneau, Guido Stochniol, Greg Shaw, Stuart Hamilton Taylor, Graham J. Hutchings, Robert Armstrong, Peneau, Virginie, Shaw, Greg, Armstrong, Robert D., Jenkins, Robert L., Dimitratos, Nikolao, Taylor, Stuart H., Zanthoff, Horst W., Peitz, Stefan, Stochniol, Guido, and Hutchings, Graham J.

Subjects
Aqueous solution, 010405 organic chemistry, Chemistry, Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Redox, Catalysis, 0104 chemical sciences, Propene, chemistry.chemical_compound, Propane, QD, Partial oxidation, ZSM-5, Selectivity
Abstract

We report the oxidation of propane under mild aqueous conditions using H2O2 as the oxidant. Various reaction conditions have been studied with a view to optimising the conversion of propane in the presence of a Fe/ ZSM-5 (30) catalyst. Process optimisation afforded 52% propane conversion in 0.5 h at a temperature of 70 oC. C3 products are shown to undergo sequential catalytic C-C scission and oxidation reactions in the presence of the catalysts, yielding C2 and C1 products. This leads to an inverse relationship between propane conversion and reaction selectivity. Addition of Cu to Fe /ZSM-5 (30) shifted reaction selectivity towards propene (≤ 34 %) with increasing conversion.

Published
2016

49. Methane oxidation using silica-supported N-bridged di-iron phthalocyanine catalyst

Author

Jose Antonio Lopez-Sanchez, Stuart Hamilton Taylor, Graham J. Hutchings, Robert Armstrong, Nikolaos Dimitratos, Michael M. Forde, Bezzu C. Grazia, Robert Leyshon Jenkins, Albert Frederick Carley, Mohd Hasbi Ab. Rahim, Neil B. McKeown, Forde, Michael M., Grazia, Bezzu C., Armstrong, Robert, Jenkins, Robert L., Rahim, Mohammed Hasbi Ab, Carley, Albert F., Dimitratos, Nikolao, Lopez-Sanchez, Jose Antonio, Taylor, Stuart H., McKeown, Neil B., and Hutchings, Graham John

Subjects
Methane oxidation, Cyclohexane, Inorganic chemistry, Aqueous two-phase system, Catalysis, Methane, Catalysi, chemistry.chemical_compound, chemistry, Anaerobic oxidation of methane, di-iron phthalocyanine catalyst, Leaching (metallurgy), Physical and Theoretical Chemistry, Hydrogen peroxide, Selectivity
Abstract

Methane oxidation in water using hydrogen peroxide with a μ-nitrido iron phthalocyanine complex grafted on silica has been investigated in detail. Methyl hydroperoxide is identified as the main primary reaction product from methane oxidation. The catalyst is unstable under reaction conditions and this is discussed. However, the unmodified silica support is also found to be active for this reaction, and in particular, a Fe/SiO 2 catalyst prepared by wet impregnation is also found to be as effective as the μ-nitrido iron phthalocyanine complex grafted on silica, with higher selectivity to useful oxygenates (>80%) and displays minimal leaching or instability. A method for the reliable quantification of CO 2 in both the gas and aqueous phase is reported as this presents a key experimental difficulty in the oxidation of methane in aqueous media. © 2012 Elsevier Inc. All rights reserved.

Published
2012
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50. Light alkane oxidation using catalysts prepared by chemical vapour impregnation: Tuning alcohol selectivity through catalyst pre-treatment

Author

Li Lu, Graham J. Hutchings, Michael M. Forde, Christopher J. Kiely, Nikolaos Dimitratos, Rebecca McVicker, Robert Leyshon Jenkins, Robert Armstrong, Ceri Hammond, Jose Antonio Lopez-Sanchez, Qian He, Peter P. Wells, Forde, Michael M., Armstrong, Robert D., McVicker, Rebecca, Wells, Peter P., Dimitratos, Nikolao, He, Qian, Lu, Li, Jenkins, Robert L., Hammond, Ceri, Lopez-Sanchez, Jose Antonio, Kiely, Christopher J., and Hutchings, Graham J.

Subjects
Alkane, chemistry.chemical_classification, Hydrogen, Reducing atmosphere, Inorganic chemistry, Chemistry (all), chemistry.chemical_element, General Chemistry, Methane, Catalysis, chemistry.chemical_compound, chemistry, Oxidation state, QD, Hydrogen peroxide, Selectivity
Abstract

Fe/ZSM-5(30) catalysts have been prepared by chemical vapour impregnation (CVI) using iron(iii) acetylacetonate as the precursor. These materials have been used for the oxidation of methane and ethane using aqueous hydrogen peroxide as oxidant. Heating in air leads to materials that exhibit high catalytic activity and give formic and acetic acid with high selectivity from methane and ethane respectively. Heat treatment of the uncalcined materials under a reducing atmosphere results in partial reduction of iron from the FeIII to FeII oxidation state with the majority of the iron being present as isolated octahedral extra-framework species having oxygen neighbours and showing no evidence of a coordination shell containing Al or Fe, as evidenced from studies using X-ray absorption and UV-Vis spectroscopies. These hydrogen treated catalysts show the same catalytic activity as their analogues formed by heating in air, but in contrast exhibit higher alcohol selectivities for both methane and ethane conversion to oxygenates and are reusable. Our findings for both the oxidation of methane and ethane indicate that the selectivity to the oxidation products, i.e. acids or alcohols, can be controlled by tuning the active site structure and/or oxidation state of the Fe species in Fe/ZSM-5. © 2014 the Partner Organisations.

Published
2014

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