6051-66-7Relevant academic research and scientific papers
A Charged Coordination Cage-Based Porous Salt
Gosselin, Aeri J.,Decker, Gerald E.,Antonio, Alexandra M.,Lorzing, Gregory R.,Yap, Glenn P. A.,Bloch, Eric D.
, p. 9594 - 9598 (2020)
Metal-organic frameworks and porous coordination cages have shown incredible promise as a result of their high tunability. However, syntheses pursuing precisely targeted mixed functionalities, such as multiple ligand types or mixed-metal compositions are often serendipitous, require postsynthetic modification strategies, or are based on complex ligand design. Herein, we present a new method for the controlled synthesis of mixed functionality metal-organic materials via the preparation of porous salts. More specifically, the combination of porous ionic molecules of opposite charge affords framework-like materials where the ratio between cationic cage and anionic cage is potentially tunable. The resulting doubly porous salt displays the spectroscopic signatures of the parent cages with increased gas uptake capacities as compared to starting materials. This approach will be widely applicable to all families of porous ions and represents a new and powerful method for the synthesis of porous solids with tailored functionalities.
BIS-BENZIMIDAZOLE COMPOUNDS AND METHODS OF USING SAME
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Paragraph 00976-00978, (2019/06/05)
Provided herein are compounds and methods for modulating abnormal repeat expansions of gene sequences. More particularly, provided are inhibitors of RNA and the uses of such inhibitors in regulating nucleotide repeat expansions, e.g., to treat Myotonic Dystrophy Type 1 (DM1 ), Myotonic Dystrophy Type 2 (DM2), Fuchs dystrophy, Huntington Disease, Amyotrophic Lateral Sclerosis, or Frontotemporal Dementia.
PROCESS FOR PRODUCING AROMATIC POLYCARBOXYLIC ACID
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Page/Page column 13-14, (2011/04/18)
A process for producing an aromatic polycarboxylic acid in which all alkyl groups are converted into carboxyl groups in a high yield by decreasing a residual amount of an intermediate product is provided. The process comprises oxygen-oxidizing an aromatic compound having a plurality of alkyl groups (e.g., durene) in the presence of a catalyst containing a cyclic imino unit having an N—OR group (wherein R represents a hydrogen atom or a protecting group for a hydroxyl group) and a transition metal co-catalyst (e.g., a cobalt compound, a manganese compound, and a zirconium compound) under heating in a lower-temperature zone and a higher-temperature zone to produce an aromatic polycarboxylic acid in which a plurality of alkyl groups are oxidized into carboxyl groups. In an initial stage of the reaction, the reaction may be conducted in a first lower-temperature zone (a reaction temperature of 60 to 120° C. and a second lower-temperature zone (an intermediate temperature zone) (a reaction temperature of 100 to 140° C.); and then, in a latter stage of the reaction, the reaction may be conducted in a higher-temperature zone (a reaction temperature of 110 to 150° C.).
ALKYL CARBOXYLATE SALTS AS SOLVENTS FOR HENKEL-RELATED PROCESSES
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Page/Page column 6-7, (2008/06/13)
Disclosed is the use of one or more molten salts or a mixture thereof for use as a reaction medium in a process for the preparation of an aromatic diacid which comprises heating an alkali metal salt of an aromatic monocarboxylic acid or asymmetrical aromatic dicarboxylic acid under pressure with carbon dioxide gas in the presence of a catalyst at suitable reaction conditions. The molten salt reaction medium provides advantages in a disproportionation reaction to produce, for example, purified terephthalic acid. In another aspect of the invention, novel methylated diacids are produced.
The complex synergy of water in the metal/bromide autoxidation of hydrocarbons caused by benzylic bromide formation
Partenheimer, Walt
, p. 297 - 306 (2007/10/03)
One of the most active and selective catalysts in homogeneous liquid phase oxidation using molecular oxygen (O2) is a mixture of cobalt, manganese and bromide salts in acetic acid. It has been used to produce hundreds of different carboxylic acids in high yield and purity including the commercial production of terephthalic acid from p-xylene. Water is normally a by-product in these reactions and it is shown here that its concentration is an important reaction variable. In anhydrous acetic acid, with reagents with sufficiently strong electron-withdrawing substitutents (toluene, 4-carboxytoluene, 4-chlorotoluene), all of the active bromide becomes inactive via benzylic bromide formation. The Co/Mn/ Br catalyst is therefore converted to a Co/Mn catalyst which is dubbed 'catalyst failure' because of its undesirable characteristics of lower activity, decreased selectivity especially towards over-oxidation and color formation. For 4-chlorotoluene, increasing the water concentration to 5 weight % initially decreases the rate of reaction but eventually is more active and selective because the oxidation and hydrolysis of the benzylic bromide allows for sufficient active catalytic bromide. It is shown that benzylic bromides do not 'promote' the reaction and that both oxidation and solvolysis of the benzylic bromide occurs during autoxidation. During polymethylbenzene oxidation, benzylic bromide formation occurs only with the most reactive methyl group. The complex factors during metal/bromide autoxidation -some favored by increased water concentration and others detrimental - are outlined.
Minor groove DNA binders as antimicrobial agents. 1. Pyrrole tetraamides are potent antibacterials against vancomycin resistant Enteroccoci and methicillin resistant Staphylococcus aureus
Dyatkina, Natalia B.,Roberts, Christopher D.,Keicher, Jesse D.,Dai, Yuqin,Nadherny, Joshua P.,Zhang, Wentao,Schmitz, Uli,Kongpachith, Ana,Fung, Kevin,Novikov, Alexander A.,Lou, Lillian,Velligan, Mark,Khorlin, Alexander A.,Chen, Ming S.
, p. 805 - 817 (2007/10/03)
A new series of short pyrrole tetraamides are described whose submicromolar DNA binding affinity is an essential component for their strong antibacterial activity. This class of compounds is related to the linked bis-netropsins and bis-distamycins, but here, only one amino-pyrrole-carboxamide unit and an amidine tail is connected to either side of a central dicarboxylic acid linker. The highest degree of DNA binding, measured by compound-induced changes in UV melting temperatures of an AT-rich DNA oligomer, was observed for flat, aromatic linkers with no inherent bent, i.e., terephthalic acid or 1,4-pyridine-dicarboxylic acid. However, the antibacterial activity is critically linked to the size of the N-alkyl substiutent of the pyrrole unit. None of the tetraamides with the commonly used methyl-pyrrole showed antibacterial activity. Isoamyl- or cyclopropylmethylene-substituted dipyrrole derivatives have the minimum inhibitory concentrations in the submicromolar range. In vitro toxicity against human T-cells was studied for all compounds. The degree to which compounds inhibited cell growth was neither directly correlated to DNA binding affinity nor directly correlated to antibacterial activity but seemed to depend strongly on the nature of the N-alkyl pyrrole substituents.
A Selective Receptor for Arginine Derivatives in Aqueous Media. Energetic Consequences of Salt Bridges That Are Highly Exposed to Water
Ngola, Sarah M.,Kearney, Patrick C.,Mecozzi, Sandro,Russell, Keith,Dougherty, Dennis A.
, p. 1192 - 1201 (2007/10/03)
Quantitative measures of salt-bridge-type interactions in a highly exposed aqueous environment have been obtained by modifying the well-studied cyclophane platform 1 to include carboxylates in close proximity to bound, cationic guests, producing hosts 2 and 3. Many guests show significantly enhanced binding to 2 and 3, but cations of the RNMe3+ type show little or no enhancement. We propose that the latter observations result from the fact that RNMe3+ compounds have very diffuse positive charges. Guests that show enhanced binding have focused regions of large, positive electrostatic potential. The highly charged 3 is able to bind very polar, very well-solvated guests, including a series of arginine-based dipeptides. Neutral, water-soluble host 4 was prepared and found to show a decreased affinity for cationic guests. We propose a novel induced dipole mechanism to rationalize these results.
Novel Dimerisation Reaction of Hydrocarbons with Cs-K-Na Alloy
Sengupta, Dibyendu,Quest, Dean E.,Grovenstein, Erling
, p. 187 - 188 (2007/10/02)
m-Xylene undergoes dimerisation with Cs-K-Na alloy at -48 deg C to give 1,1',4,4'-tetrahydro-3,3',5,5'-tetramethylbiphenyl (3) while o- and p-xylenes do not follow such a reaction under identical conditions.
