Metal–Organic Frameworks of Vanadium as Catalysts for Conversion of Methane to Acetic Acid

Phan, Anh,Czaja, Alexander U.,Ga&#x301,ndara, Felipe,Knobler, Carolyn B.,Yaghi, Omar M. American Chemical Society 2011 Inorganic chemistry Vol.50 No.16

<P>A catalytic system combining the high activity of homogeneous catalysts and the ease of use of heterogeneous catalysts for methane activation is reported. The vanadium-containing metal–organic frameworks (MOFs) MIL-47 and MOF-48 are found to have high catalytic activity and chemical stability. They convert methane selectively to acetic acid with 70% yield (490 TON) based on K<SUB>2</SUB>S<SUB>2</SUB>O<SUB>8</SUB> as an oxidant. Isotopic labeling experiments showed that two methane molecules are converted to the produced acetic acid. The MOF catalysts are reusable and remain catalytically active for several recycling steps without losing their crystalline structures.</P><P>The vanadium-containing metal−organic framework MOF-48 catalyzes the selective direct oxidation of methane to acetic acid. The yield is 49% (based on K<SUB>2</SUB>S<SUB>2</SUB>O<SUB>8</SUB> as an oxidant), 490 TON, at 80 °C in a trifluoroacetic acid solvent.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/inocaj/2011/inocaj.2011.50.issue-16/ic201396m/production/images/medium/ic-2011-01396m_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ic201396m'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ic201396m'>ACS Electronic Supporting Info</A></P>

Mesenchymal Cell–Specific MyD88 Signaling Promotes Systemic Dissemination of <i>Salmonella Typhimurium</i> via Inflammatory Monocytes

Kim, Donghyun,Seo, Sang-Uk,Zeng, Melody Y.,Kim, Wan-Uk,Kamada, Nobuhiko,Inohara, Naohiro,Nú,ú,n&#x303,ez, Gabriel The American Association of Immunologists, Inc. 2017 JOURNAL OF IMMUNOLOGY Vol.199 No.4

<P>Enteric pathogens including Salmonella enteric serovar Typhimurium can breach the epithelial barrier of the host and spread to systemic tissues. In response to infection, the host activates innate immune receptors via the signaling molecule MyD88, which induces protective inflammatory and antimicrobial responses. Most of these innate immune responses have been studied in hematopoietic cells, but the role of MyD88 signaling in other cell types remains poorly understood. Surprisingly, we found that Dermo1-Cre;Myd88(fl/fl) mice with mesenchymal cell-specific deficiency of MyD88 were less susceptible to orogastric and i.p. S. Typhimurium infection than their Myd88(fl/fl) littermates. The reduced susceptibility of Dermo1-Cre; Myd88(fl/fl) mice to infection was associated with lower loads of S. Typhimurium in the liver and spleen. Mutant analyses revealed that S. Typhimurium employs its virulence type III secretion system 2 to promote its growth through MyD88 signaling pathways in mesenchymal cells. Inflammatory monocytes function as a major cell population for systemic dissemination of S. Typhimurium. Mechanistically, mesenchymal cell-specific MyD88 signaling promoted CCL2 production in the liver and spleen and recruitment of inflammatory monocytes to systemic organs in response to S. Typhimurium infection. Consistently, MyD88 signaling in mesenchymal cells enhanced the number of phagocytes including Ly6C(hi)Ly6G(-) inflammatory monocytes harboring S. Typhimurium in the liver. These results suggest that S. Typhimurium promotes its systemic growth and dissemination through MyD88 signaling pathways in mesenchymal cells.</P>

Hytramycins V and I, Anti-<i>Mycobacterium tuberculosis</i> Hexapeptides from a <i>Streptomyces hygroscopicus</i> Strain

Cai, Geping,Napolitano, Jose&#x301,G.,McAlpine, James B.,Wang, Yuehong,Jaki, Birgit U.,Suh, Joo-Won,Yang, Seung Hwan,Lee, In-Ae,Franzblau, Scott G.,Pauli, Guido F.,Cho, Sanghyun American Chemical Society and American Society of 2013 Journal of natural products Vol.76 No.11

<P>Thirty-five thousand actinomycete extracts were screened for anti-<I>Mycobacterium tuberculosis</I> (<I>M. tb</I>) activity, followed by C<SUB>18</SUB> cartridge fractionation of 37 prioritized extracts. Based on MICs against replicating and nonreplicating <I>M. tb</I>, and IC<SUB>50</SUB> values against Vero cells to generate selectivity indices, seven fractions from seven different strains were selected for further examination. When cultured in G.S.S. media and extracted with ethyl acetate, the <I>Streptomyces hygroscopicus</I> strain ECUM 14046 yielded an extract with promising anti-<I>M. tb</I> activity and a well-defined chromatographic profile. Fractionation by preparative HPLC and subsequent structure elucidation of two active fractions using 1D- and 2D-NMR and MS methods revealed the presence of two cyclohexapeptides, hytramycins V and I, each containing three unusual piperazic acid moieties. The use of <SUP>1</SUP>H iterative full spin analysis (HiFSA) on both hytramycins confirmed that quantum mechanics-simulated spectra match the experimental data, and all <I>J</I><SUB>H,H</SUB> and δ<SUB>H</SUB> values are consistent with the proposed structures. The absolute configuration of each amino acid moiety was determined by Marfey’s method. The MICs against replicating and, more importantly, nonreplicating <I>M. tb</I> fall into the range of some existing second-line anti-TB drugs, such as streptomycin and capreomycin, respectively. The activities were maintained against <I>M. tb</I> strains that represent the major global clades, as well as H<SUB>37</SUB>Rv-isogenic strains that are resistant to individual clinical anti-TB drugs.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jnprdf/2013/jnprdf.2013.76.issue-11/np400145u/production/images/medium/np-2013-00145u_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/np400145u'>ACS Electronic Supporting Info</A></P>

Reverse Shape Selectivityin the Liquid-PhaseAdsorption of Xylene Isomers in Zirconium Terephthalate MOF UiO-66

Moreira, MarianaA.,Santos, Joa&#x303,o C.,Ferreira, Alexandre F. P.,Loureiro, Jose&#x301,M.,Ragon, Florence,Horcajada, Patricia,Shim, Kyu-E.,Hwang, Young-K.,Lee, U.-Hwang,Chang, Jong-S.,Serre, Christi American ChemicalSociety 2012 Langmuir Vol.28 No.13

<P>Powder, agglomerates, and tablets of the microporous zirconium(IV)terephthalate metal–organic framework UiO-66 were evaluatedfor the selective adsorption and separation of xylene isomers in theliquid phase using <I>n</I>-heptane as the eluent. Pulseexperiments, performed at 313 K in the presence of <I>n</I>-heptane, revealed the <I>o</I>-xylene preference of thismaterial, which was further confirmed by binary and multicomponentbreakthrough experiments in the presence of <I>m</I>- and <I>p</I>-xylene, resulting in selectivities at 313 K of 1.8 and2.4 with regards to <I>m</I>-xylene and <I>p</I>-xylene, respectively. Additionally, because <I>p</I>-xyleneis the less retained isomer, UiO-66 presents a selectivity patternthat is reverse of that of the xylenes' molecular dimension with respectto shape selectivity. The shaping of the material as tablets did notsignificantly change its selectivity toward the <I>o</I>-xylene isomer or toward <I>p</I>-xylene, which was theless retained isomer, despite a loss in capacity. Finally, the selectivitybehavior of UiO-66 in the liquid <I>n</I>-heptane phasemakes it a suitable material for <I>o</I>-xylene separationin the extract (heavy product) or <I>p</I>-xylene separationin the raffinate (light product) by simulated moving bed technology.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2012/langd5.2012.28.issue-13/la3004118/production/images/medium/la-2012-004118_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la3004118'>ACS Electronic Supporting Info</A></P>

Syngas Purification by Porous Amino-Functionalized Titanium Terephthalate MIL-125

Regufe, Maria Joa&#x303,o,Tamajon, Javier,Ribeiro, Ana M.,Ferreira, Alexandre,Lee, U-Hwang,Hwang, Young Kyu,Chang, Jong-San,Serre, Christian,Loureiro, Jose&#x301,M.,Rodrigues, Ali&#x301,rio E. American Chemical Society 2015 ENERGY AND FUELS Vol.29 No.7

<P>The adsorption equilibrium of carbon dioxide (CO<SUB>2</SUB>), carbon monoxide (CO), nitrogen (N<SUB>2</SUB>), methane (CH<SUB>4</SUB>), and hydrogen (H<SUB>2</SUB>) was studied at 303, 323, and 343 K and pressures up to 7 bar in titanium-based metal–organic framework (MOF) granulates, amino-functionalized titanium terephthalate MIL-125(Ti)_NH<SUB>2</SUB>. The affinity of the different adsorbates toward the adsorbent presented the following order: CO<SUB>2</SUB> > CH<SUB>4</SUB> > CO > N<SUB>2</SUB> > H<SUB>2</SUB>, from the most adsorbed to the least adsorbed component. Subsequently, adsorption kinetics and multicomponent adsorption equilibrium were studied by means of single, binary, and ternary breakthrough curves at 323 K and 4.5 bar with different feed mixtures. Both studies are complementary and aim the syngas purification for two different applications, hydrogen production and H<SUB>2</SUB>/CO composition adjustment, to be used as feed in the Fischer–Tropsch processes. The isosteric heats were calculated from the adsorption equilibrium isotherms and are 21.9 kJ mol<SUP>–1</SUP> for CO<SUB>2</SUB>, 14.6 kJ mol<SUP>–1</SUP> for CH<SUB>4</SUB>, 13.4 kJ mol<SUP>–1</SUP> for CO, and 11.7 kJ mol<SUP>–1</SUP> for N<SUB>2</SUB>. In the overall pressure and temperature range, the adsorption equilibrium isotherms were well-regressed against the Langmuir model. The multicomponent breakthrough experimental results allowed for validation of the adsorption equilibrium predicted by the multicomponent extension of the Langmuir isotherm and validation of the fixed-bed mathematical model. To conclude, two pressure swing adsorption (PSA) cycles were designed and performed experimentally, one for hydrogen purification from a 30/70% CO<SUB>2</SUB>/H<SUB>2</SUB> mixture (hydrogen purity was 100% with a recovery of 23.5%) and a second PSA cycle to obtain a light product with a H<SUB>2</SUB>/CO ratio between 2.2 and 2.4 to feed to Fischer–Tropsch processes. The experimental cycle produced a light stream with a H<SUB>2</SUB>/CO ratio of 2.3 and a CO<SUB>2</SUB>-enriched stream with 86.6% purity as a heavy product. The CO<SUB>2</SUB> recovery was 93.5%.</P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ef5b00975'>ACS Electronic Supporting Info</A></P>

Discovery and Characterization of the Tuberculosis Drug Lead Ecumicin

Gao, Wei,Kim, Jin-Yong,Chen, Shao-Nong,Cho, Sang-Hyun,Choi, Jongkeun,Jaki, Birgit U.,Jin, Ying-Yu,Lankin, David C.,Lee, Ji-Ean,Lee, Sun-Young,McAlpine, James B.,Napolitano, Jose&#x301,G.,Franzblau, Sc American Chemical Society 2014 ORGANIC LETTERS Vol.16 No.23

<P>The new tuberculosis (TB) lead ecumicin (<B>1</B>), a cyclic tridecapeptide, was isolated from <I>Nonomuraea sp.</I> MJM5123, following a high-throughput campaign for anti-TB activity. The large molecular weight of 1599 amu detected by LC-HR-MS precluded the initial inference of its molecular formula. The individual building blocks were identified by extensive NMR experiments. The resulting two possible planar structures were distinguished by LC-MS<SUP>2</SUP>. Determination of absolute configuration and unambiguous structural confirmation were carried out by X-ray crystallography and Marfey’s analysis.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/orlef7/2014/orlef7.2014.16.issue-23/ol5026603/production/images/medium/ol-2014-026603_0003.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ol5026603'>ACS Electronic Supporting Info</A></P>