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Extracellular Gluco-Oligosaccharide Degradation By Caulobacter Crescentus, Gerald Presley, Matthew Payea, Logan Hurst, Annie Egan, Brandon Martin, Gopal Periyannan
Extracellular Gluco-Oligosaccharide Degradation By Caulobacter Crescentus, Gerald Presley, Matthew Payea, Logan Hurst, Annie Egan, Brandon Martin, Gopal Periyannan
Faculty Research and Creative Activity
The oligotrophic bacterium Caulobacter crescentus has the ability to metabolize various organic molecules, including plant structural carbohydrates, as a carbon source. The nature of β-glucosidase (BGL)-mediated gluco-oligosaccharide degradation and nutrient transport across the outer membrane in C. crescentus was investigated. All gluco-oligosaccharides tested (up to celloheptose) supported growth in M2 minimal media but not cellulose or CM-cellulose. The periplasmic and outer membrane fractions showed highest BGL activity, but no significant BGL activity was observed in the cytosol or extracellular medium. Cells grown in cellobiose showed expression of specific BGLs and TonB-dependent receptors (TBDRs). Carbonyl cyanide 3-chlorophenylhydrazone lowered the rate of …
High-Pressure Cryogelation Of Nanosilica And Surface Properties Of Cryosilicas, V Gun'ko, V Turov, V Zarko, G Prykhod'ko, O Remez, R Leboda, J Skubiszewska-Zieba, E Pahklov, Jonathan Blitz
High-Pressure Cryogelation Of Nanosilica And Surface Properties Of Cryosilicas, V Gun'ko, V Turov, V Zarko, G Prykhod'ko, O Remez, R Leboda, J Skubiszewska-Zieba, E Pahklov, Jonathan Blitz
Faculty Research and Creative Activity
Silica cryogels (cryosilicas) in a powder state were synthesized with different concentrations of fumed silica A-300 (CA-300 = 5-20 wt.%), sonicated in aqueous suspension, then frozen at -14 oC at different pressures in a high-pressure stainless steel reactor (a freezing bomb), and dried in air at room temperature. To analyze the effects of low temperature and high pressure, samples were also prepared at -14 oC or room temperature and standard pressure. The structural and adsorption properties of the powder materials were studied using nitrogen adsorption, high-resolution transmission electron microscopy, infrared spectroscopy, thermogravimetry, low-temperature 1H NMR spectroscopy and thermally stimulated depolarization …
High-Pressure Cryogelation Of Nanosilica And Surface Properties Of Cryosilicas, V M. Gun'ko, V V. Turov, V I. Zarko, G P. Prykhod'ko, O S. Remez, R Leboda, J Skubiszewska-Zieba, E M. Pahklov, Jonathan Blitz
High-Pressure Cryogelation Of Nanosilica And Surface Properties Of Cryosilicas, V M. Gun'ko, V V. Turov, V I. Zarko, G P. Prykhod'ko, O S. Remez, R Leboda, J Skubiszewska-Zieba, E M. Pahklov, Jonathan Blitz
Faculty Research and Creative Activity
Silica cryogels (cryosilicas) in a powder state were synthesized with different concentrations of fumed silica A-300 (CA-300 = 5-20 wt.%), sonicated in aqueous suspension, then frozen at -14 oC at different pressures in a high-pressure stainless steel reactor (a freezing bomb), and dried in air at room temperature. To analyze the effects of low temperature and high pressure, samples were also prepared at -14 oC or room temperature and standard pressure. The structural and adsorption properties of the powder materials were studied using nitrogen adsorption, high-resolution transmission electron microscopy, infrared spectroscopy, thermogravimetry, low-temperature 1H NMR spectroscopy and thermally stimulated depolarization …
Room Temperature Syntheses Of Entirely Diverse Substituted Β-Fluorofurans, Li Yan, Kraig A. Wheeler, Roman Dembinski
Room Temperature Syntheses Of Entirely Diverse Substituted Β-Fluorofurans, Li Yan, Kraig A. Wheeler, Roman Dembinski
Faculty Research and Creative Activity
Synthesis of highly substituted 3-fluorofurans is reported. The sequence began with preparation of tertbutyldimethylsilyl alk-1-en-3-yn-1-yl ethers from 1,4-disubstituted alk-3-yn-1-ones. Subsequent fluorination of alkenynyl silyl ethers with Selectfluor gave 2-fluoroalk-3-yn-1-ones in almost quantitative yield. Subsequent 5-endo-dig cyclizations using chlorotriphenylphosphine gold(I)/silver trifluoromethanesulfonate (5/5 mol%), N-bromo- or N-iodosuccinimide and gold(I) chloride/zinc bromide (5/20 mol%), all at room temperature, provided a facile method for the generation of substituted 3-fluoro-, 3-bromo-4-fluoro-, and 3-fluoro-4-iodofurans in good yields. Also, 2,2-difluoroalk-3-yn-1-ones were prepared by fluorination of alk-3-yn-1-ones under organocatalytic conditions. The structures of (Z)-tertbutyldimethylsilyl but-1-en-3-yn-1-yl ether, 3-bromo-4-fluorofuran, and 3-fluoro-4-(phenylethynyl)furan were confirmed by X-ray crystallography.
Microwave, Infrared And Raman Spectra, R0 Structural Parameters, Ab Initio Calculations And Vibrational Assignment Of 1-Fluoro-1-Silacyclopentanea), James R. Durig, Savitha S. Panikar, Daniel A. Obenchain, Brandon J. Bills, Patrick M. Lohan, Rebecca A. Peebles, Sean A. Peebles, Peter Groner, Gamil A. Guirgis, Michael D. Johnston
Microwave, Infrared And Raman Spectra, R0 Structural Parameters, Ab Initio Calculations And Vibrational Assignment Of 1-Fluoro-1-Silacyclopentanea), James R. Durig, Savitha S. Panikar, Daniel A. Obenchain, Brandon J. Bills, Patrick M. Lohan, Rebecca A. Peebles, Sean A. Peebles, Peter Groner, Gamil A. Guirgis, Michael D. Johnston
Faculty Research and Creative Activity
The microwave spectrum (6500–18 500 MHz) of 1-fluoro-1-silacyclopentane, c-C4H8SiHF has been recorded and 87 transitions for the 28Si, 29Si, 30Si, and 13C isotopomers have been assigned for a single conformer. Infrared spectra (3050-350 cm−1) of the gas and solid and Raman spectrum (3100-40 cm−1) of the liquid have also been recorded. The vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twist form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers to be saddle points with nearly the same energies but much …
Microwave, Infrared And Raman Spectra, R0 Structural Parameters, Ab Initio Calculations And Vibrational Assignment Of 1-Fluoro-1-Silacyclopentanea), James Durig, Savitha Panikar, Daniel Obenchain, Brandon Bills, Patrick Lohan, Rebecca Peebles, Sean Peebles, Peter Groner, Gamil Guirgis, Michael Johnston
Microwave, Infrared And Raman Spectra, R0 Structural Parameters, Ab Initio Calculations And Vibrational Assignment Of 1-Fluoro-1-Silacyclopentanea), James Durig, Savitha Panikar, Daniel Obenchain, Brandon Bills, Patrick Lohan, Rebecca Peebles, Sean Peebles, Peter Groner, Gamil Guirgis, Michael Johnston
Faculty Research and Creative Activity
The microwave spectrum (6500–18 500 MHz) of 1-fluoro-1-silacyclopentane, c-C4H8SiHF has been recorded and 87 transitions for the 28Si, 29Si, 30Si, and 13C isotopomers have been assigned for a single conformer. Infrared spectra (3050-350 cm−1) of the gas and solid and Raman spectrum (3100-40 cm−1) of the liquid have also been recorded. The vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twist form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers to be saddle points with nearly the same energies but much …
Valine Sulfonamidecinnamic Acid Asymmetric Crystal Reactions, Kraig A. Wheeler, Steven H. Malehorn, Annie E. Egan
Valine Sulfonamidecinnamic Acid Asymmetric Crystal Reactions, Kraig A. Wheeler, Steven H. Malehorn, Annie E. Egan
Faculty Research and Creative Activity
Racemic and homochiral valine sulfonamidecinnamic acidscrystallize with components aligned by use of thecomplementary features of hydrogen bonds and moleculartopology to give supramolecular dimers. These discretemotifs effectively organize adjacent olefins for UV initiated10 single-crystal-to-single-crystal [2+2] photodimerizationreactions. The racemic crystals produce inversion relatedcyclobutane products, while the desymmetrized crystallinearchitectures of the homochiral phase promote asymmetricphotodimerization with 90% conversion.
6-[(4-Hydroxyphenyl)Diazenyl]- 1,10-Phenanthrolin-1-Ium Chloride Monohydrate, Akram Hazeen, Yan Zhang, Minchong Mao, Kraig A. Wheeler, Mark E. Mcguire
6-[(4-Hydroxyphenyl)Diazenyl]- 1,10-Phenanthrolin-1-Ium Chloride Monohydrate, Akram Hazeen, Yan Zhang, Minchong Mao, Kraig A. Wheeler, Mark E. Mcguire
Faculty Research and Creative Activity
In the cation of the title molecular salt, C18H13N4O+_Cl__H2O, the dihedral angle between the mean planes of the 1,10- phenanthroline system and the phenol ring is 14.40 (19)_. The crystal packing is stabilized by O—H_ _ _O hydrogen bonds, weak N—H_ _ _Cl and O—H_ _ _Cl intermolecular interactions and _—_ stacking interactions [centroid–centroid distance = 3.6944 (13) and 3.9702 (12) [A °]
Enantiocontrolled Solid-State Photodimerizations Via A Chiral Sulfonamidecinnamic Acid, Kraig A. Wheeler, Joshua D. Wiseman, Rebecca C. Grive
Enantiocontrolled Solid-State Photodimerizations Via A Chiral Sulfonamidecinnamic Acid, Kraig A. Wheeler, Joshua D. Wiseman, Rebecca C. Grive
Faculty Research and Creative Activity
The supramolecular patterns of three polymorphs of a chiral sulfonamidecinnamic acid reveal components effectively organized into predetermined hydrogen-bonded dimers with favorable <3.8A ° olefin spacing for enantioselective single-crystal-to-single-crystal [2 + 2] photodimerization reactions.
Photoreactive Crystalline Quasiracemates, Rebecca C. Grove, Steven H. Malehorn, Meghan E. Breen, Kraig A. Wheeler
Photoreactive Crystalline Quasiracemates, Rebecca C. Grove, Steven H. Malehorn, Meghan E. Breen, Kraig A. Wheeler
Faculty Research and Creative Activity
Rationally designed racemic and quasiracemic sulfonamidecinnamic acids assemble to give hydrogen-bonded dimers with coplanar alignment of neighboring olefins. The quasiracemate phase contains near inversion-related motifs with chemically distinct components forming supramolecular heterodimers that undergo asymmetric photodimerization.
10,12-Dimethylpteridino[6,7-F][1,10]- Phenanthroline-11,13(10h,12h)-Dione– Chloroform (1/1), Waynie Olaprath, Jennifer Rodin, Kraig A. Wheeler, Mark E. Mcguire
10,12-Dimethylpteridino[6,7-F][1,10]- Phenanthroline-11,13(10h,12h)-Dione– Chloroform (1/1), Waynie Olaprath, Jennifer Rodin, Kraig A. Wheeler, Mark E. Mcguire
Faculty Research and Creative Activity
In the title co-crystal, C18H12N6O2_CHCl3, intramolecular Cl3C—H_ _ _N hydrogen-bonding interactions occur between a single CHCl3 and both N atoms at the 1,10-positions on the phenanthroline portion of the molecule. The interplanar distance between inversion-related molecules is 3.241 (2) A ° .
(+-)-3-Carboxy-2-(Imidazol-3-Ium-1-Yl)- Propanoate, Sara A. Reeb, Marlesa C. Shields, Kraig A. Wheeler
(+-)-3-Carboxy-2-(Imidazol-3-Ium-1-Yl)- Propanoate, Sara A. Reeb, Marlesa C. Shields, Kraig A. Wheeler
Faculty Research and Creative Activity
The title compound, C7H8N2O4, crystallizes as a zwitterion, with molecules organized into molecular sheets via carboxyl– carboxylate and N+—H_ _ _carboxylate contacts. These sheets are constructed from translationally related molecules that further link to neighboring motifs via _-stacking [centroid– centroid distance 3.504 (3) A ° ] and weak C—H_ _ _O contacts.
2-Aminopyrimidine-3,3,3-Triphenyl- Propanoic Acid (1/1), Mateusz F. Serafin, Kraig A. Wheeler
2-Aminopyrimidine-3,3,3-Triphenyl- Propanoic Acid (1/1), Mateusz F. Serafin, Kraig A. Wheeler
Faculty Research and Creative Activity
The title bimolecular compound, C4H5N3·C21H18O2, constructed from 2-aminopyrimidine and 3,3,3-triphenylpropanoic acid, forms a tetramolecular hydrogen-bonded motif via O—H...N, N—H...O and N—H...N contacts. This aggregate organizes to give crystal-packing motifs with hydrophilic and hydrophobic regions.
Bis(1,2-DihydroxyBenzene) HexaMethylEneTetraMine, Philias Daka, Kraig A. Wheeler
Bis(1,2-DihydroxyBenzene) HexaMethylEneTetraMine, Philias Daka, Kraig A. Wheeler
Faculty Research and Creative Activity
The title binary complex, 2C6H6O2·C6H12N4, is constructed from hexamethylenetetramine, positioned about a twofold symmetry operator, and 1,2-dihydroxybenzene. Each of the four tertiary amine N atoms participates in O—H⋯N contacts that produce molecular strands that propagate along the c axis.
(Acetonitrile-Κn){2-[Bis(2-Pyridylethyl)Amino]Ethanol-Κ4n,N′,N′′,O}Zinc(Ii) Bis(Perchlorate) Monohydrate, Hong-Chang Liang, Marcel M. Hetu, Kraig A. Wheeler, Lev N. Zakharov, Arnold L. Rheingold
(Acetonitrile-Κn){2-[Bis(2-Pyridylethyl)Amino]Ethanol-Κ4n,N′,N′′,O}Zinc(Ii) Bis(Perchlorate) Monohydrate, Hong-Chang Liang, Marcel M. Hetu, Kraig A. Wheeler, Lev N. Zakharov, Arnold L. Rheingold
Faculty Research and Creative Activity
In the title compound, [Zn(C2H3N)(C16H21N3O)](ClO4)2·H2O, the ZnII ion is coordinated by two pyridyl N atoms, one amine N atom, and an ethanol O atom from the N,N′,N′′,O-tetradentate 2-[bis(2-pyridylethyl)amino]ethanol donor ligand. The fifth coordination site is filled by an acetonitrile N atom, and there is one solvent water molecule in the asymmetric unit. The 2+ charge of the cationic portion of the complex is balanced by two perchlorate counter-anions.
N-(2-Aminobenzyl)-N,N-Bis(Quinolin- 2-Ylmethyl)Amine, Abhijit Mitra, Pamela J. Seaton, Kraig A. Wheeler
N-(2-Aminobenzyl)-N,N-Bis(Quinolin- 2-Ylmethyl)Amine, Abhijit Mitra, Pamela J. Seaton, Kraig A. Wheeler
Faculty Research and Creative Activity
The title new diquinaldine derivative, C27H24N4, forms molecular assemblies organized by intermolecular quinoline π–π stacking [3.356 (3) and 3.440 (3) Å] and both inter- and intramolecular N—H⋯N hydrogen bonds [3.039 (3)–3.104 (3) Å and 129 (2)–172 (2)°]. The combination of such interactions provides readily definable contacts that propagate along each crystallographic axis.
Strychninium (S)-2-(2-BromoPhenOxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry
Strychninium (S)-2-(2-BromoPhenOxy)Propanoate 1.4-Hydrate, Kraig A. Wheeler, Aaron M. Lineberry
Faculty Research and Creative Activity
In the title molecular salt, C21H23N2O2+·C9H8BrO3−·1.4H2O, the components are linked by intermolecular C—O−⋯H—+N and OW—H⋯O interactions.
A Molecular Salt Of Tricyanomethanide Anion And A N,N9- Dianisylphenazinium Dication: Cooperative Affects Of Methoxy…Methoxy And Cmn…N+ Intermolecular Contacts, Scott E. Mckay, Kraig A. Wheeler, Silas C. Blackstock
A Molecular Salt Of Tricyanomethanide Anion And A N,N9- Dianisylphenazinium Dication: Cooperative Affects Of Methoxy…Methoxy And Cmn…N+ Intermolecular Contacts, Scott E. Mckay, Kraig A. Wheeler, Silas C. Blackstock
Faculty Research and Creative Activity
A molecular salt of tricyanomethanide anion and a N,N9- dianisylphenazinium dication forms extended supramolecular assemblies that consist of unusual methoxy…methoxy and CMN…N+ intermolecular contacts.
11,12-Bis(2,2-DimethylPropYl)-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler
11,12-Bis(2,2-DimethylPropYl)-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler
Faculty Research and Creative Activity
The title compound, C26H32, was retrieved as one of three products from the reaction of tert-butyllithium with 11,12-dimethylene-9,10-dihydroethenoanthracene and 4,5-diiodopentacyclo[4.3.0.02,4.03,8.05,7]nonane. The structure shows the expected ethenoanthracene geometry with molecules arranged via van der Waals surfaces.
11-(2,2-Dimethylpropyl)-12-{2-[12-(2,2-Dimethylpropyl)- 9,10-Dihydro-9,10-Ethenoanthracen-11-Yl]- Ethyl}-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler, Glenn P.A. Yap
11-(2,2-Dimethylpropyl)-12-{2-[12-(2,2-Dimethylpropyl)- 9,10-Dihydro-9,10-Ethenoanthracen-11-Yl]- Ethyl}-9,10-Dihydro-9,10-Ethenoanthracene, Joseph P. Herres, Mark A. Forman, Kraig A. Wheeler, Glenn P.A. Yap
Faculty Research and Creative Activity
Reaction of tert-butyllithium with 11,12-dimethylene-9,10- dihydro-9,10-ethanoanthracene and 4,5-diiodopentacyclo- [4.3.0.02,4.03,8.05,7]nonane gives three products, one of which crystallizes from petroleum ether as the title compound, C44H46, (I). Molecules of (I) are positioned on inversion centers (Z0 = 0.5) in the space group P21/n and lack any discernible intermolecular interactions.
2,2':6',2"-Terpyridine 1,1"-Dioxide Dihydrate, Kraig A. Wheeler, Scott E. Mckay, Robert W. Lashlee Iii
2,2':6',2"-Terpyridine 1,1"-Dioxide Dihydrate, Kraig A. Wheeler, Scott E. Mckay, Robert W. Lashlee Iii
Faculty Research and Creative Activity
No abstract provided.
2,2':6',2"-Terpyridine N,N',N"-Trioxide, Kraig A. Wheeler, Scott E. Mckay, Silas C. Blackstock
2,2':6',2"-Terpyridine N,N',N"-Trioxide, Kraig A. Wheeler, Scott E. Mckay, Silas C. Blackstock
Faculty Research and Creative Activity
No abstract provided.
The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose L. Alonso, Juan C. Lopez, Robert L. Kuczkowski, Sean A. Peebles, Rebecca A. Peebles, Faith C. Boman, Elfi Kraka, Dieter Cremer
The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose L. Alonso, Juan C. Lopez, Robert L. Kuczkowski, Sean A. Peebles, Rebecca A. Peebles, Faith C. Boman, Elfi Kraka, Dieter Cremer
Faculty Research and Creative Activity
The fluorobenzene–hydrogen chloride π-hydrogen-bonded complex has been studied by high resolution microwave spectroscopy and ab initio calculations. Rotational spectra of the C6H5F–H35Cl, C6H5F–H37Cl, and C6D5F–H35Cl isotopomers were assigned using pulsed molecular beam techniques in a Fourier-transform microwave spectrometer. The spectra are consistent with a structure of the complex in which the HCl is above the fluorobenzene ring near the ring center, similar to the benzene–HCl prototype dimer. An analysis of the inertial data and the chlorine quadrupole coupling tensor results in two mathematically possible locations for the HCl subunit with respect to the fluorobenzene arising from sign ambiguities in interpreting …
The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose Alonso, Juan Lopez, Robert Kuczkowski, Sean Peebles, Rebecca Peebles, Faith Boman, Elfi Kraka, Dieter Cremer
The Microwave Spectrum, Ab Initio Analysis, And Structure Of The Fluorobenzene–Hydrogen Chloride Complex, M. Eugenia Sanz, Sonia Antolinez, Jose Alonso, Juan Lopez, Robert Kuczkowski, Sean Peebles, Rebecca Peebles, Faith Boman, Elfi Kraka, Dieter Cremer
Faculty Research and Creative Activity
The fluorobenzene–hydrogen chloride π-hydrogen-bonded complex has been studied by high resolution microwave spectroscopy and ab initio calculations. Rotational spectra of the C6H5F–H35Cl, C6H5F–H37Cl, and C6D5F–H35Cl isotopomers were assigned using pulsed molecular beam techniques in a Fourier-transform microwave spectrometer. The spectra are consistent with a structure of the complex in which the HCl is above the fluorobenzene ring near the ring center, similar to the benzene–HCl prototype dimer. An analysis of the inertial data and the chlorine quadrupole coupling tensor results in two mathematically possible locations for the HCl subunit with respect to the fluorobenzene arising from sign ambiguities in interpreting …
(N2o)2⋅So2: Rotational Spectrum And Structure Of The First Van Der Waals Trimer Containing Sulfur Dioxide, Rebecca A. Peebles, Robert L. Kuczkowski
(N2o)2⋅So2: Rotational Spectrum And Structure Of The First Van Der Waals Trimer Containing Sulfur Dioxide, Rebecca A. Peebles, Robert L. Kuczkowski
Faculty Research and Creative Activity
No abstract provided.
(N2o)2⋅So2: Rotational Spectrum And Structure Of The First Van Der Waals Trimer Containing Sulfur Dioxide, Rebecca Peebles, Robert Kuczkowski
(N2o)2⋅So2: Rotational Spectrum And Structure Of The First Van Der Waals Trimer Containing Sulfur Dioxide, Rebecca Peebles, Robert Kuczkowski
Faculty Research and Creative Activity
No abstract provided.