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Full-Text Articles in Organic Chemistry

Homoleptic Trivalent Tris(Alkyl) Rare Earth Compounds, Aradhana Pindwal, Kaking Yan, Smita Patnaik, Bradley M. Schmidt, Arkady Ellern, Igor I. Slowing, Cheolbeom Bae, Aaron D. Sadow Sep 2019

Homoleptic Trivalent Tris(Alkyl) Rare Earth Compounds, Aradhana Pindwal, Kaking Yan, Smita Patnaik, Bradley M. Schmidt, Arkady Ellern, Igor I. Slowing, Cheolbeom Bae, Aaron D. Sadow

Igor I. Slowing

Homoleptic tris(alkyl) rare earth complexes Ln{C(SiHMe2)(3)}(3) (Ln = La, 1a; Ce, 1b; Pr, 1c; Nd, 1d) are synthesized in high yield from LnI(3)THF(n) and 3 equiv of KC(SiHMe2)(3). X-ray diffraction studies reveal 1a-d are isostructural, pseudo-C-3-symmetric molecules that contain two secondary Li <- HSi interactions per alkyl ligand (six total). Spectroscopic assignments are supported by comparison with Ln{C(SiDMe2)(3)}(3) and DFT calculations. The Ln <- HSi and terminal SiH exchange rapidly on the NMR time scale at room temperature, but the two motifs are resolved at low temperature. Variable-temperature NMR studies provide activation parameters for the exchange process in la (Delta H-double dagger = 8.2(4) kcal.mol(-1); Delta S-double dagger = -1(2) cal.mol(-1)K(-1)) and 1a-d(9) (Delta H-double dagger = 7.7(3) kcal.mol(-1); Delta S-double dagger = -4(2) cal.mol(-1)K(-1)). Comparisons of lineshapes, rate constants, (k(H)/k(D)), and slopes of ln (k/T) vs 1/T plots for la and 1a-d(9) reveal that an inverse isotope effect dominates at low temperature. DFT calculations identify four low-energy intermediates containing five beta-Si-H -> Ln and one gamma-C-H -> Ln. The calculations also suggest the pathway for Ln <- HSi/SiH exchange involves rotation of a single C(SiHMe2)(3) ligand that is coordinated to the Ln center through the Ln-C bond and one secondary interaction. These robust organometallic compounds persist in solution and in the solid state up to 80 degrees C, providing potential for their use in a range of synthetic applications. For example, reactions of Ln{C(SiHMe2)(3)}(3) and ancillary proligands, such as bis-1,1-(4,4-dimethyl-2-oxazolinyl)ethane (HMeC(Ox(Me2))(2)) give {MeC(Ox(Me2))(2)}Ln{C(SiHMe2)(3)}(2), and reactions with disilazanes provide solvent-free lanthanoid tris(disilazides).


Homoleptic Trivalent Tris(Alkyl) Rare Earth Compounds, Aradhana Pindwal, Kaking Yan, Smita Patnaik, Bradley M. Schmidt, Arkady Ellern, Igor I. Slowing, Cheolbeom Bae, Aaron D. Sadow Sep 2019

Homoleptic Trivalent Tris(Alkyl) Rare Earth Compounds, Aradhana Pindwal, Kaking Yan, Smita Patnaik, Bradley M. Schmidt, Arkady Ellern, Igor I. Slowing, Cheolbeom Bae, Aaron D. Sadow

Aaron D. Sadow

Homoleptic tris(alkyl) rare earth complexes Ln{C(SiHMe2)(3)}(3) (Ln = La, 1a; Ce, 1b; Pr, 1c; Nd, 1d) are synthesized in high yield from LnI(3)THF(n) and 3 equiv of KC(SiHMe2)(3). X-ray diffraction studies reveal 1a-d are isostructural, pseudo-C-3-symmetric molecules that contain two secondary Li <- HSi interactions per alkyl ligand (six total). Spectroscopic assignments are supported by comparison with Ln{C(SiDMe2)(3)}(3) and DFT calculations. The Ln <- HSi and terminal SiH exchange rapidly on the NMR time scale at room temperature, but the two motifs are resolved at low temperature. Variable-temperature NMR studies provide activation parameters for the exchange process in la (Delta H-double dagger = 8.2(4) kcal.mol(-1); Delta S-double dagger = -1(2) cal.mol(-1)K(-1)) and 1a-d(9) (Delta H-double dagger = 7.7(3) kcal.mol(-1); Delta S-double dagger = -4(2) cal.mol(-1)K(-1)). Comparisons of lineshapes, rate constants, (k(H)/k(D)), and slopes of ln (k/T) vs 1/T plots for la and 1a-d(9) reveal that an inverse isotope effect dominates at low temperature. DFT calculations identify four low-energy intermediates containing five beta-Si-H -> Ln and one gamma-C-H -> Ln. The calculations also suggest the pathway for Ln <- HSi/SiH exchange involves rotation of a single C(SiHMe2)(3) ligand that is coordinated to the Ln center through the Ln-C bond and one secondary interaction. These robust organometallic compounds persist in solution and in the solid state up to 80 degrees C, providing potential for their use in a range of synthetic applications. For example, reactions of Ln{C(SiHMe2)(3)}(3) and ancillary proligands, such as bis-1,1-(4,4-dimethyl-2-oxazolinyl)ethane (HMeC(Ox(Me2))(2)) give {MeC(Ox(Me2))(2)}Ln{C(SiHMe2)(3)}(2), and reactions with disilazanes provide solvent-free lanthanoid tris(disilazides).


Biogenic Volatiles Emitted From Four Cold-Hardy Grape Cultivars During Ripening, Somchai Rice, Devin L. Maurer, Anne Fennell, Murlidhar Dharmadhikari, Jacek A. Koziel Sep 2019

Biogenic Volatiles Emitted From Four Cold-Hardy Grape Cultivars During Ripening, Somchai Rice, Devin L. Maurer, Anne Fennell, Murlidhar Dharmadhikari, Jacek A. Koziel

Devin L. Maurer

In this research dataset, we summarize for the first time volatile organic compounds (VOCs) emitted in vivo from ripening wine grapes. We studied four cold-hardy cultivars grown in the Midwestern U.S.: St. Croix, Frontenac, Marquette, and La Crescent. These cultivars have gained popularity among local growers and winemakers, but still very little is known about their performance compared with long-established V. viniferagrapes. Volatiles were collected using two novel approaches: biogenic emissions from grape clusters on a vine and single grape berries. A third approach was headspace collection of volatiles from crushed grapes. Solid-phase microextraction (SPME) was used to collect ...


Stacked Antiaromatic Porphyrins, Ryo Nozawa, Hiroko Tanaka, Won-Young Cha, Yongseok Hong, Ichiro Hisaki, Soji Shimizu, Ji-Young Shin, Tim Kowalczyk, Stephan Irle, Dongho Kim, Hiroshi Shinokubo May 2019

Stacked Antiaromatic Porphyrins, Ryo Nozawa, Hiroko Tanaka, Won-Young Cha, Yongseok Hong, Ichiro Hisaki, Soji Shimizu, Ji-Young Shin, Tim Kowalczyk, Stephan Irle, Dongho Kim, Hiroshi Shinokubo

Tim Kowalczyk

Aromaticity is a key concept in organic chemistry. Even though this concept has already been theoretically extrapolated to three dimensions, it usually still remains restricted to planar molecules in organic chemistry textbooks. Stacking of antiaromatic π-systems has been proposed to induce three-dimensional aromaticity as a result of strong frontier orbital interactions. However, experimental evidence to support this prediction still remains elusive so far. Here we report that close stacking of antiaromatic porphyrins diminishes their inherent antiaromaticity in the solid state as well as in solution. The antiaromatic stacking furthermore allows a delocalization of the π-electrons, which enhances the two-photon absorption ...


Application Of The Picoloyl Substituent In Carbohydrate Chemistry, Michael Mannino, Alexei V. Demchenko May 2019

Application Of The Picoloyl Substituent In Carbohydrate Chemistry, Michael Mannino, Alexei V. Demchenko

Michael Mannino

Stereocontrol of glycosylation reactions is a constant struggle in the field of synthetic carbohydrate chemistry. The application of the picoloyl (Pico) substituent can offer a numerous stereocontrolling avenues. The most popular application is the Hydrogen-bond-mediated Aglycone Delivery (HAD) method that provides excellent selectivity in the glycosylation of a variety of sugar substrates. The HAD method relies on the formation of an intermolecular hydrogen bond between the nitrogen atom of the Pico substituent on the glycosyl donor with the hydroxyl group of the glycosyl acceptor. This interaction provides a facial preference for the nucleophilic attack and hence provides powerful stereocontrol for ...


Scale Up Isolation Of Aaptamine For In Vivo Evaluation Indicates Its Neurobiological Activity Is Linked To The Delta Opioid Receptor, Nicole L. Mcintosh, Eptisam Lambo, Laura Millan-Lobo, Fei Li, Li He, Phillip Crews, Jennifer L. Whistler, Tyler Johnson Mar 2019

Scale Up Isolation Of Aaptamine For In Vivo Evaluation Indicates Its Neurobiological Activity Is Linked To The Delta Opioid Receptor, Nicole L. Mcintosh, Eptisam Lambo, Laura Millan-Lobo, Fei Li, Li He, Phillip Crews, Jennifer L. Whistler, Tyler Johnson

Tyler Johnson

Opioid receptors belong to the large superfamily of seven transmembrane-spanning (7TM) G protein-coupled receptors (GPCRs). As a class, GPCRs are of fundamental physiological importance mediating the actions of the majority of known neurotransmitters and hormones. The Mu, Delta, and Kappa (MOP, DOP, KOP) opioid receptors are particularly intriguing members of this receptor family as they are the targets involved in many neurobiological diseases such as addiction, pain, stress, anxiety, and depression. Recently we discovered that the aaptamine class of marine sponge derived natural products exhibit selective agonist activity in vitro for the DOP versus MOP receptor. Our findings may explain ...


Spatial Mapping And Profiling Of Metabolite Distributions During Germination, Adam D. Feenstra, Liza E. Alexander, Zhihong Song, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee Nov 2018

Spatial Mapping And Profiling Of Metabolite Distributions During Germination, Adam D. Feenstra, Liza E. Alexander, Zhihong Song, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee

Robbyn Anand

Germination is a highly complex process by which seeds begin to develop and establish themselves as viable organisms. In this paper, we utilize a combination of GC-MS, LC-fluorescence, and mass spectrometry imaging (MSI) approaches to profile and visualize the metabolic distributions of germinating seeds from two different inbreds of maize seeds, B73 and Mo17. GC and LC analyses demonstrate that the two inbreds are highly differentiated in their metabolite profiles throughout the course of germination, especially with regard to amino acids, sugar alcohols, and small organic acids. Crude dissection of the seed followed by GC-MS analysis of polar metabolites also ...


Modulating Patterns Of Two-Phase Flow With Electric Fields, Dingsheng Liu, Bejan Hakimi, Michael Volny, Joelle Rolfs, Robbyn Anand, Rantisek Turecek, Daniel T. Chiu Nov 2018

Modulating Patterns Of Two-Phase Flow With Electric Fields, Dingsheng Liu, Bejan Hakimi, Michael Volny, Joelle Rolfs, Robbyn Anand, Rantisek Turecek, Daniel T. Chiu

Robbyn Anand

This paper describes the use of electro-hydrodynamic actuation to control the transition between three major flow patterns of an aqueous-oil Newtonian flowin a microchannel: droplets, beads-on-a-string (BOAS), and multi-stream laminar flow. We observed interesting transitional flow patterns between droplets and BOAS as the electric field was modulated. The ability to control flow patterns of a two-phase fluid in a microchannel adds to the microfluidic tool box and improves our understanding of this interesting fluid behavior.


Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen Oct 2018

Flexible Laser-Induced Graphene For Nitrogen Sensing In Soil, Nate T. Garland, Eric S. Mclamore, Nicholas D. Cavallaro, Deyny Mendivelso-Perez, Emily A. Smith, Dapeng Jing, Jonathan C. Claussen

Jonathan C. Claussen

Flexible graphene electronics are rapidly gaining interest, but their widespread implementation has been impeded by challenges with ink preparation, ink printing, and post-print annealing processes. Laser-induced graphene (LIG) promises a facile alternative by creating flexible graphene electronics on polyimide substrates through a one-step laser writing fabrication method. Herein we demonstrate the use of LIG, created through a low-cost UV laser, for electrochemical ion selective sensing of plant-available nitrogen (i.e., both ammonium and nitrate ions: NH4+ and NO3-) in soil samples. The laser used to create the LIG was operated at distinct pulse rates (10, 20, 30, 40, and 50 ...


Reintroducing Explicit Solvent To A Solvent-Free Coarse-Grained Model, Seung Ha Kim, Monica H. Lamm Oct 2017

Reintroducing Explicit Solvent To A Solvent-Free Coarse-Grained Model, Seung Ha Kim, Monica H. Lamm

Monica H. Lamm

A unique coarse-grained modeling scheme that combines a systematic, solvent-free multiscale coarse-graining algorithm for a complex macromolecule with an existing coarse-grained solvent model is proposed. We show that this procedure efficiently and reliably describes the interactions for complex macromolecules, using the specific example of dendrimers binding phenanthrenes in water. The experimentally measured binding capacity is predicted by the unique coarse-grained modeling approach; the conditions for this simulation are beyond what could be reasonably simulated with an all-atom molecular dynamics simulation.


Oligomers Of Cyclopentadithiophene-Vinylene In Aromatic And Quinoidal Versions And Redox Species With Intermediate Forms, Paula Mayorga Burrezo, Rocío Domínguez, José L. Zafra, Ted M. Pappenfus, Pilar De La Cruz, Lorena Welte, Daron E. Janzen, Juan T. López Navarrete, Fernando Langa, Juan Casado Sep 2017

Oligomers Of Cyclopentadithiophene-Vinylene In Aromatic And Quinoidal Versions And Redox Species With Intermediate Forms, Paula Mayorga Burrezo, Rocío Domínguez, José L. Zafra, Ted M. Pappenfus, Pilar De La Cruz, Lorena Welte, Daron E. Janzen, Juan T. López Navarrete, Fernando Langa, Juan Casado

Daron E Janzen, Ph.D.

No abstract provided.


Optimizing Synthesis Of Substituted Oxadiazole Based Liquid Crystal Compounds.Pptx, Blake Bordokas Sep 2017

Optimizing Synthesis Of Substituted Oxadiazole Based Liquid Crystal Compounds.Pptx, Blake Bordokas

Blake Bordokas

The liquid crystalline phase is a sensitive state of matter in which molecules exist between a solid and a liquid. Molecules in this state possess the ability to be reoriented by an electric field, which makes them extremely useful in display technology for devices such as computer monitors, smart phones, etc. A group of bent-core liquid crystalline compounds show a particularly unique type of liquid crystal phase that has promising traits which could be exploited to improve display technology. In this project we propose a simpler, more cost effective synthesis for these liquid crystals which we hope will allow us ...


Ionic Liquid Extraction Unveils Previously Occluded Humic-Bound Iron In Peat Soil Pore Water, Timothy J. Veverica, Evan S. Kane, Amy Marcarelli, Sarah A. Green Aug 2017

Ionic Liquid Extraction Unveils Previously Occluded Humic-Bound Iron In Peat Soil Pore Water, Timothy J. Veverica, Evan S. Kane, Amy Marcarelli, Sarah A. Green

Amy Marcarelli

Globally, peatland ecosystems store tremendous amounts of C relative to their extent on the landscape, largely owing to saturated soils which limit decomposition. While there is still considerable uncertainty regarding CO2 production potential below the water table in peatland ecosystems, extracellular Fe reduction has been suggested as a dominant pathway for anaerobic metabolism. However, colorimetric methods commonly used to quantitate Fe and partition between redox species are known to be unreliable in the presence of complex humic substances, which are common in peatland pore water. We evaluated both the standard o-phenanthroline (o-P) Method and an ionic liquid extraction (ILE) Method ...


Using Metastable-State Photoacid For Fluorescence And Ph Modulation, Renan S. Gongora, Juan Arias, Parth K. Patel, Karin Y. Chumbimuni-Torres Apr 2017

Using Metastable-State Photoacid For Fluorescence And Ph Modulation, Renan S. Gongora, Juan Arias, Parth K. Patel, Karin Y. Chumbimuni-Torres

Juan Arias

The transfer of protons lies at the core of numerous biological and chemical processes. Herein we propose a visible-light triggered molecular system that allows to reversibly tailor acidity and, additionally, fluorescence. This robust bi-functional system opens up the doors for novel studies on acid-mediated processes by incorporating fluorescence. The two photosensitive compounds used for this study, a Metastable-state Photoacids (mPAH) and a boron-dipyrromethene (BODIPY) derivative, allow for consistent modulation of both fluorescence and pH over multiple cycles.


7Β-Hydroxy­Artemisinin, Paulo B. Carvalho, Bo Liu, Yunshan Wu, John S. Williamson, Mitchell A. Avery Apr 2017

7Β-Hydroxy­Artemisinin, Paulo B. Carvalho, Bo Liu, Yunshan Wu, John S. Williamson, Mitchell A. Avery

John S. Williamson

Crystals of the title compound [systematic name: (3R,6R,7S,8aR,9R,12aR)-7-hydr­oxy-3,6,9-trimethyl­octa­hydro-3,12-ep­oxy[1,2]dioxepino[4,3-i]isochromen-10(3H)-one], C15H22O6, were obtained from microbial transformation of artemisinin by a culture of Cunninghamella elegans. The stereochemistry of the compound is consistent with the spectroscopic findings in previously published works. A weak O—H⋯O hydrogen bond occurs in the crystal structure, together with intermolecular C—H⋯O hydrogen bonds.


Homoleptic Divalent Dialkyl Lanthanide-Catalyzed Cross-Dehydrocoupling Of Silanes And Amines, Aradhana Pindwal, Arkady Ellern, Aaron D. Sadow Feb 2017

Homoleptic Divalent Dialkyl Lanthanide-Catalyzed Cross-Dehydrocoupling Of Silanes And Amines, Aradhana Pindwal, Arkady Ellern, Aaron D. Sadow

Aaron D. Sadow

The rare-earth bis(alkyl) compound Sm{C(SiHMe2)3}2THF2 (1b) is prepared by the reaction of samarium(II) iodide and 2 equiv of KC(SiHMe2)3. This synthesis is similar to that of previously reported Yb{C(SiHMe2)3}2THF2 (1a), and compounds 1a,b are isostructural. Reactions of 1b and 1 or 2 equiv of B(C6F5)3 afford SmC(SiHMe2)3HB(C6F5)3THF2 (2b) or Sm{HB(C6F5)3}2THF2 (3b), respectively, and 1,3-disilacyclobutane {Me2Si-C(SiHMe2)2}2 as a byproduct. Bands from 2300 to 2400 cm–1 assigned to νBH in the IR spectra and ...


Cyclopentadienyl-Bis(Oxazoline) Magnesium And Zirconium Complexes In Aminoalkene Hydroaminations, Naresh Eedugurala, Megan Hovey, Hung-An Ho, Barun Jana, Nicole L. Lampland, Arkady Ellern, Aaron D. Sadow Feb 2017

Cyclopentadienyl-Bis(Oxazoline) Magnesium And Zirconium Complexes In Aminoalkene Hydroaminations, Naresh Eedugurala, Megan Hovey, Hung-An Ho, Barun Jana, Nicole L. Lampland, Arkady Ellern, Aaron D. Sadow

Aaron D. Sadow

A new class of cyclopentadiene-bis(oxazoline) compounds and their piano-stool-type organometallic complexes have been prepared as catalysts for hydroamination of aminoalkenes. The two compounds MeC(OxMe2)2C5H5 (BoMCpH; OxMe2 = 4,4-dimethyl-2-oxazoline) and MeC(OxMe2)2C5Me4H (BoMCptetH) are synthesized from C5R4HI (R = H, Me) and MeC(OxMe2)2Li. These cyclopentadiene-bis(oxazolines) are converted into ligands that support a variety of metal centers in piano-stool-type geometries, and here we report the preparation of Mg, Tl, Ti, and Zr compounds. BoMCpH and BoMCptetH react with MgMe2(O2C4H8)2 to give the magnesium methyl complexes {BoMCp}MgMe and {BoMCptet}MgMe. BoMCpH and BoMCptetH are ...


Role Of Co2 As A Soft Oxidant For Dehydrogenation Of Ethylbenzene To Styrene Over A High-Surface-Area Ceria Catalyst, Li Zhang, Zili Wu, Nicholas C. Nelson, Aaron D. Sadow, Igor I. Slowing Feb 2017

Role Of Co2 As A Soft Oxidant For Dehydrogenation Of Ethylbenzene To Styrene Over A High-Surface-Area Ceria Catalyst, Li Zhang, Zili Wu, Nicholas C. Nelson, Aaron D. Sadow, Igor I. Slowing

Aaron D. Sadow

Catalytic performance and the nature of surface adsorbates were investigated for high-surface-area ceria during the ethylbenzene oxidative dehydrogenation (ODH) reaction using CO2 as a soft oxidant. The high surface area ceria material was synthesized using a template-assisted method. The interactions among ethylbenzene, styrene, and CO2 on the surface of ceria and the role of CO2 for the ethylbenzene ODH reaction have been investigated in detail by using activity test, in situ diffuse reflectance infrared and Raman spectroscopy. CO2 as an oxidant not only favored the higher yield of styrene but also inhibited the deposition of coke during the ethylbenzene ODH ...


Β-Sih-Containing Tris(Silazido) Rare-Earth Complexes As Homogeneous And Grafted Single-Site Catalyst Precursors For Hydroamination, Naresh Eedugurala, Zhuoran Wang, Kaking Yan, Kasuni Boteju, Umesh Chaudhary, Takeshi Kobayashi, Arkady Ellern, Igor I. Slowing, Marek Pruski, Aaron D. Sadow Feb 2017

Β-Sih-Containing Tris(Silazido) Rare-Earth Complexes As Homogeneous And Grafted Single-Site Catalyst Precursors For Hydroamination, Naresh Eedugurala, Zhuoran Wang, Kaking Yan, Kasuni Boteju, Umesh Chaudhary, Takeshi Kobayashi, Arkady Ellern, Igor I. Slowing, Marek Pruski, Aaron D. Sadow

Aaron D. Sadow

A series of homoleptic rare-earth silazido compounds and their silica-grafted derivatives were prepared to compare spectroscopic and catalytic features under homogeneous and interfacial conditions. Trivalent tris(silazido) compounds Ln{N(SiHMe2)tBu}3 (Ln = Sc (1), Y (2), Lu (3)) are prepared in high yield by salt metathesis reactions. Solution-phase and solid-state characterization of 1–3 by NMR and IR spectroscopy and X-ray diffraction reveals Ln↼H–Si interactions. These features are retained in solvent-coordinated 2·Et2O, 2·THF, and 3·THF. The change in spectroscopic features characterizing the secondary interactions (νSiH, 1JSiH) from the unactivated SiH in the silazane ...


Strategies For The Production Of Cell Wall-Deconstructing Enzymes In Lignocellulosic Biomass And Their Utilization For Biofuel Production, Sang-Hyuck Park, Rebecca Garlock Ong, Mariam Sticklen Oct 2016

Strategies For The Production Of Cell Wall-Deconstructing Enzymes In Lignocellulosic Biomass And Their Utilization For Biofuel Production, Sang-Hyuck Park, Rebecca Garlock Ong, Mariam Sticklen

Rebecca Ong

Microbial cell wall-deconstructing enzymes are widely used in the food, wine, pulp and paper, textile, and detergent industries and will be heavily utilized by cellulosic biorefineries in the production of fuels and chemicals. Due to their ability to use freely available solar energy, genetically engineered bioenergy crops provide an attractive alternative to microbial bioreactors for the production of cell wall-deconstructing enzymes. This review article summarizes the efforts made within the last decade on the production of cell wall-deconstructing enzymes in planta for use in the deconstruction of lignocellulosic biomass. A number of strategies have been employed to increase enzyme yields ...


Pharmacological Validation Of An Inward-Rectifier Potassium (Kir) Channel As An Insecticide Target In The Yellow Fever Mosquito Aedes Aegypti, Matthew F. Rouhier, Rene Raphemot, Jerod S. Denton, Peter M. Piermarini Oct 2016

Pharmacological Validation Of An Inward-Rectifier Potassium (Kir) Channel As An Insecticide Target In The Yellow Fever Mosquito Aedes Aegypti, Matthew F. Rouhier, Rene Raphemot, Jerod S. Denton, Peter M. Piermarini

Matthew F Rouhier

Mosquitoes are important disease vectors that transmit a wide variety of pathogens to humans, including those that cause malaria and dengue fever. Insecticides have traditionally been deployed to control populations of disease-causing mosquitoes, but the emergence of insecticide resistance has severely limited the number of active compounds that are used against mosquitoes. Thus, to improve the control of resistant mosquitoes there is a need to identify new insecticide targets and active compounds for insecticide development. Recently we demonstrated that inward rectifier potassium (Kir) channels and small molecule inhibitors of Kir channels offer promising new molecular targets and active compounds, respectively ...


Eliciting Renal Failure In Mosquitoes With A Small-Molecule Inhibitor Of Inward-Rectifying Potassium Channels, Matthew F. Rouhier, Rene Raphemot, Corey R. Hopkins, Rocco D. Gogliotti, Kimberly M. Lovel, Rebecca M. Hine, Dhairyasheel Ghosalkar, Anthony Longo, Klaus W. Beyenbach, Jerod S. Denton, Peter M. Piermarini Oct 2016

Eliciting Renal Failure In Mosquitoes With A Small-Molecule Inhibitor Of Inward-Rectifying Potassium Channels, Matthew F. Rouhier, Rene Raphemot, Corey R. Hopkins, Rocco D. Gogliotti, Kimberly M. Lovel, Rebecca M. Hine, Dhairyasheel Ghosalkar, Anthony Longo, Klaus W. Beyenbach, Jerod S. Denton, Peter M. Piermarini

Matthew F Rouhier

Mosquito-borne diseases such as malaria and dengue fever take a large toll on global health. The primary chemical agents used for controlling mosquitoes are insecticides that target the nervous system. However, the emergence of resistance in mosquito populations is reducing the efficacy of available insecticides. The development of new insecticides is therefore urgent. Here we show that VU573, a small-molecule inhibitor of mammalian inward-rectifying potassium (Kir) channels, inhibits a Kir channel cloned from the renal (Malpighian) tubules of Aedes aegypti (AeKir1). Injection of VU573 into the hemolymph of adult female mosquitoes (Ae. aegypti) disrupts the production and excretion of urine ...


A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph W. Meisel, George W. Gokel Aug 2016

A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph W. Meisel, George W. Gokel

George Gokel

Established transfection methodology often uses commercial reagents, which must be formed into liposomes in a sequence of about half a dozen steps. The simplified method reported here is a direct lipid mixing approach that requires fewer steps, less manipulation, and is less time-consuming. Results are comparable to those obtained with more commonly used methods, as judged by a variety of analytical techniques and by comparisons of transfection results. The method reported here may be applied to non-liposome-forming compounds, thereby greatly expanding the range of structures that can be tested for transfection ability.


A New Science, And A New Profession: Sugar Chemistry In Louisiana, 1885-1895, John Alfred Heitmann Jul 2016

A New Science, And A New Profession: Sugar Chemistry In Louisiana, 1885-1895, John Alfred Heitmann

John A. Heitmann

Between 1885 and 1895 the Louisiana sugar industry experienced a scientific and technological revolution in methods, process apparatus, and scale of operations. The animal-powered mills and open kettles characteristic of the antebellum period were supplanted by large, technically designed, and scientifically controlled central factories . In 1880 there were approximately 1,000 sugar houses in Louisiana with an average annual production of 110 long tons of sugar per house. By 1900 fewer than 300 factories constituted the state's sugar industry, but yearly production averaged over 980 long tons for each sugar house. One commentator of the period, Mark Twain, described ...


A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin Mar 2016

A Sodium Salt Of The Dimer Of Boronoterephthalic Acid Anhydride, Scott Simmons, Albert Fratini, Vladimir Benin

Albert Fratini

The title compound, sodium bis­(6-carb­oxy-1-hy­droxy-3-oxo-1,3-dihydro-2,1-benzoxaborol-1-yl)oxidanium, Na+·C16H15B2O13-, was prepared in two steps from 2-bromo-p-xylene. Its crystal structure was determined at 140 K and has triclinic (P) symmetry. The compound presents a unique structural motif, including two units of the cyclic anhydride of boronoterephthalic acid, joined by a protonated, and thereby trivalent, oxonium center. Association in the crystal is realized by complementary hydrogen bonding of the carboxyl groups, as well as by coordination of the sodium cations to the oxygen centers on the five-membered rings.


Expression Of Acyl Carrier Proteins In Spinach, Katherine Schmid, J. Ohlrogge Feb 2016

Expression Of Acyl Carrier Proteins In Spinach, Katherine Schmid, J. Ohlrogge

Katherine Schmid

Dr. Schmid and Dr. Ohlrogge's contribution to the Proceedings of the 9th International Symposium on Plant Lipids; Wye, England; July 8-13, 1990.


Cyclopropane Fatty Acid Expression In Plants, Katherine Schmid Feb 2016

Cyclopropane Fatty Acid Expression In Plants, Katherine Schmid

Katherine Schmid

Pants [sic] are transformed with a bacterial cyclopropane fatty acid synthase gene to produce lipids containing cyclopropane fatty acids. Using this technology dihydrosterculate is produced in oilseed crops such as rape.


Interrogating Metabolism In Brain Cancer, Travis Salzillo, Jingzhe Hu, Linda Nguyen, Nicholas Whiting, Jaehyuk Lee, Joseph Weygand, Prasanta Dutta, Shivanand Pudakalakatti, Niki Zacharias Millward, Seth Gammon, Frederick F. Lang, Amy B. Heimberger, Pratip Bhattacharya Dec 2015

Interrogating Metabolism In Brain Cancer, Travis Salzillo, Jingzhe Hu, Linda Nguyen, Nicholas Whiting, Jaehyuk Lee, Joseph Weygand, Prasanta Dutta, Shivanand Pudakalakatti, Niki Zacharias Millward, Seth Gammon, Frederick F. Lang, Amy B. Heimberger, Pratip Bhattacharya

Nicholas Whiting

Many existing and emerging techniques of interrogating metabolism in brain cancer are at an early stage of development. A few clinical trials that employ these techniques are in progress in patients with brain cancer to establish the clinical efficacy of these techniques. It is likely that in vivo metabolomics and metabolic imaging is the next frontier in brain cancer diagnosis and assessing therapeutic efficacy.


Controlling Microbial Contamination During Hydrolysis Of Afex-Pretreated Corn Stover And Switchgrass: Effects On Hydrolysate Composition, Microbial Response And Fermentation, Jose Serate, Dan Xie, Edward Pohlmann, Charles Donald Jr., Mahboubeh Shabani, Li Hinchman, Alan Higbee, Mick Mcgee, Alex La Reau, Grace E. Klinger, Sheena Li, Chad L. Myers, Charles Boone, Donna M. Bates, Dave Cavalier, Dustin Eilert, Lawrence G. Oates, Gregg Sanford, Trey K. Sato, Bruce Dale, Robert Landrick, Jeff Piotrowski, Rebecca G. Gong, Yaoping Zhang Nov 2015

Controlling Microbial Contamination During Hydrolysis Of Afex-Pretreated Corn Stover And Switchgrass: Effects On Hydrolysate Composition, Microbial Response And Fermentation, Jose Serate, Dan Xie, Edward Pohlmann, Charles Donald Jr., Mahboubeh Shabani, Li Hinchman, Alan Higbee, Mick Mcgee, Alex La Reau, Grace E. Klinger, Sheena Li, Chad L. Myers, Charles Boone, Donna M. Bates, Dave Cavalier, Dustin Eilert, Lawrence G. Oates, Gregg Sanford, Trey K. Sato, Bruce Dale, Robert Landrick, Jeff Piotrowski, Rebecca G. Gong, Yaoping Zhang

Rebecca Ong

Background
Microbial conversion of lignocellulosic feedstocks into biofuels remains an attractive means to produce sustainable energy. It is essential to produce lignocellulosic hydrolysates in a consistent manner in order to study microbial performance in different feedstock hydrolysates. Because of the potential to introduce microbial contamination from the untreated biomass or at various points during the process, it can be difficult to control sterility during hydrolysate production. In this study, we compared hydrolysates produced from AFEX-pretreated corn stover and switchgrass using two different methods to control contamination: either by autoclaving the pretreated feedstocks prior to enzymatic hydrolysis, or by introducing antibiotics ...


C–N Bond Rotation And E–Z Isomerism In Some N-Benzyl-N-Methylcarbamoyl Chlorides: A Dft Study, Michael Horwath, Vladimir Benin Nov 2015

C–N Bond Rotation And E–Z Isomerism In Some N-Benzyl-N-Methylcarbamoyl Chlorides: A Dft Study, Michael Horwath, Vladimir Benin

Vladimir Benin

The current report presents the first theoretical study of the restricted CN bond rotation in carbamoyl chlorides. Several N-benzyl-N-methylcarbamoyl chlorides were investigated, with varying pattern of substitution in the aromatic ring. Optimizations and frequency calculations were conducted employing DFT at the B3LYP/6-31+G(d) level of theory. Each of the studied structures exhibits a pair of rotamers (s-Z and s-E), generated upon rotation around the C(O)N bond. The s-E isomer is the global minimum in every case, but the preference for it is usually less than 1 kcal/mol. Two possible transition state structures were identified for ...