Tag: M.W=200-250

Sauvee, Claire published the artcileTailoring of Polarizing Agents in the bTurea Series for Cross-Effect Dynamic Nuclear Polarization in Aqueous Media, Application of 2-(2-((tert-Butyldimethylsilyl)oxy)ethoxy)ethan-1-amine, the publication is Chemistry – A European Journal (2016), 22(16), 5598-5606, database is CAplus and MEDLINE.

A series of 18 nitroxide biradicals derived from bTurea has been prepared, and their enhancement factors ¦Å (¹H) in cross-effect dynamic nuclear polarization (CE DNP) NMR experiments at 9.4 and 14.1 T and 100 K in a DNP-optimized glycerol/water matrix (“DNP juice”) have been studied. We observe that ¦Å (¹H) is strongly correlated with the substituents on the polarizing agents, and its trend is discussed in terms of different mol. parameters: solubility, average e-e distance, relative orientation of the nitroxide moieties, and electron spin relaxation times. We show that too short an e-e distance or too long a T_1e can dramatically limit ¦Å (¹H). Our study also shows that the mol. structure of AMUPol is not optimal and its ¦Å (¹H) could be further improved through stronger interaction with the glassy matrix and a better orientation of the TEMPO moieties. A new AMUPol derivative introduced here provides a better ¦Å (¹H) than AMUPol itself (by a factor of ca. 1.2).

Chemistry – A European Journal published new progress about 215297-17-9. 215297-17-9 belongs to catalysis-chemistry, auxiliary class Linker,PROTAC Linker, name is 2-(2-((tert-Butyldimethylsilyl)oxy)ethoxy)ethan-1-amine, and the molecular formula is C10H25NO2Si, Application of 2-(2-((tert-Butyldimethylsilyl)oxy)ethoxy)ethan-1-amine.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Stevanato, Gabriele published the artcileOpen and Closed Radicals: Local Geometry around Unpaired Electrons Governs Magic-Angle Spinning Dynamic Nuclear Polarization Performance, COA of Formula: C10H25NO2Si, the publication is Journal of the American Chemical Society (2020), 142(39), 16587-16599, database is CAplus and MEDLINE.

The development of magic-angle spinning dynamic nuclear polarization (MAS DNP) has allowed at.-level characterization of materials for which conventional solid-state NMR is impractical due to the lack of sensitivity. The rapid progress of MAS DNP has been largely enabled through the understanding of rational design concepts for more efficient polarizing agents (PAs). Here, we identify a new design principle which has so far been overlooked. We find that the local geometry around the unpaired electron can change the DNP enhancement by an order of magnitude for two otherwise identical conformers. We present a set of 13 new stable mono- and dinitroxide PAs for MAS DNP NMR where this principle is demonstrated. The radicals are divided into two groups of isomers, named open (O-) and closed (C-), based on the ring conformations in the vicinity of the N-O bond. In all cases, the open conformers exhibit dramatically improved DNP performance as compared to the closed counterparts. In particular, a new urea-based biradical named HydrOPol and a mononitroxide O-MbPyTol yield enhancements of 330 ¡À 60 and 119 ¡À 25, resp., at 9.4 T and 100 K, which are the highest enhancements reported so far in the aqueous solvents used here. We find that while the conformational changes do not significantly affect electron spin-spin distances, they do affect the distribution of the exchange couplings in these biradicals. Electron spin echo envelope modulation (ESEEM) experiments suggest that the improved performance of the open conformers is correlated with higher solvent accessibility.

Journal of the American Chemical Society published new progress about 215297-17-9. 215297-17-9 belongs to catalysis-chemistry, auxiliary class Linker,PROTAC Linker, name is 2-(2-((tert-Butyldimethylsilyl)oxy)ethoxy)ethan-1-amine, and the molecular formula is C4H6BrFO2, COA of Formula: C10H25NO2Si.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Basinger, Mark A. published the artcileStructural requirements for mercury(II) antidotes, Computed Properties of 38260-01-4, the publication is Journal of Inorganic and Nuclear Chemistry (1981), 43(6), 1419-25, database is CAplus.

In order to determine the structural requirements for Hg(II) antidotes, stability constants were determined for Hg(II) complexes with thiol-containing ligands, and the relative efficacy was examined of 29 compounds as antidotes for Hg poisoning. Examples are not found in which 2 thiol groups on the same chelate mol. are simultaneously bonded to the same Hg(II) species, and Hg(II) complexes becoming 2 S donors generally have a bond angle of ?180¡ã between these 2 bonds. In general, mols. which are not potential chelates are inferior as antidotes; the presence of a second donor group is required, apparently to provide the necessary kinetic stability of the complex. In the case of dithiols, Hg may move back and forth from a S donor site to another but may not (and possibly cannot) bind firmly and simultaneously to both donor sites.

Journal of Inorganic and Nuclear Chemistry published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C6H20Cl2N4, Computed Properties of 38260-01-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

McCann, Malachy published the artcileSynthesis, x-ray crystal structure and catalytic activity of the manganese(II) complex [Mn(bdoa)(H₂O)₃] (bdoaH₂ = Benzene-1,2-dioxyacetic acid), Recommanded Product: 2,2-(1,2-Phenylenebis(oxy))diacetic acid, the publication is Polyhedron (1996), 15(13), 2117-20, database is CAplus.

Benzene-1,2-dioxyacetic acid (bdoaH₂) reacts with Mn(CH₃CO₂)₂¡¤4H₂O in an EtOH-H₂O mixture to give the Mn(II) complex [Mn(bdoa)(H₂O)₃]. The x-ray crystal structure of the complex shows the metal to be pseudo seven-coordinate. The quadridentate bdoa^2- dicarboxylate ligand forms an essentially planar girdle around the metal, being strongly bonded transoid by a carboxylate O atom from each of the two carboxylate moieties (mean Mn-O 2.199 ?) and also weakly chelated by the two internal ether O O atoms (mean Mn-O 2.413 ?). The coordination sphere about the Mn is completed by three H₂O mols. (mean Mn-O 2.146 ?) lying in a meridional plane orthogonal to that of the bdoa^2- ligand. Magnetic, conductivity and voltammetry data for the complex are given, and its use as a catalyst for the disproportionation of H₂O₂ is described.

Polyhedron published new progress about 5411-14-3. 5411-14-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2,2-(1,2-Phenylenebis(oxy))diacetic acid, and the molecular formula is C10H10O6, Recommanded Product: 2,2-(1,2-Phenylenebis(oxy))diacetic acid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Stoica, Ligia published the artcileSeparation of recovery by flotation of molybdenum from residual waters, Recommanded Product: Dodecylamineacetate, the publication is Revistade Chimie (Bucharest, Romania) (1990), 41(7-8), 586-90, database is CAplus.

The flotation recovery of Mo from wastewaters containing 10-150 mg MoO₄^2- was optimized by using Fe(OH)₃ as a carrier and laurylamine acetate and romegal as a collector. The recovery of MoO₄^2- was 95-99% at pH 9-11. Exptl. data related to the effects of surface tension, electrokinetic potential, pH and Mo concentration on the flotation effectiveness are given.

Revistade Chimie (Bucharest, Romania) published new progress about 2016-56-0. 2016-56-0 belongs to catalysis-chemistry, auxiliary class Active Esterification, name is Dodecylamineacetate, and the molecular formula is C13H15NO6S, Recommanded Product: Dodecylamineacetate.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Verardo, Giancarlo published the artcileRevisitation of the reaction between aniline and formaldehyde. Observation of a stable monomeric N-methylene aromatic amine, Application In Synthesis of 2909-77-5, the publication is Journal of the Chemical Society, Chemical Communications (1985), 1787-8, database is CAplus.

Reaction of 2,6-(Me₂CH)₂C₆H₃NH₂ with poly(oxymethylene) (I) at ?100¡ã gave 2,6-(Me₂CH)₂C₆H₃N:CH₂ (II), characterized by spectroscopic and anal. data. Hydrolysis, reduction, and acetylation reactions of II are reported. Analogous reaction of I with 2,6-Me₂C₆H₃NH₂ gave an equilibrium mixture of 2,6-Me₂C₆H₃N:CH₂ and an oligomeric species.

Journal of the Chemical Society, Chemical Communications published new progress about 2909-77-5. 2909-77-5 belongs to catalysis-chemistry, auxiliary class Amine,Benzene, name is 2,6-Diisopropyl-N,N-dimethylaniline, and the molecular formula is C7H10O4, Application In Synthesis of 2909-77-5.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Bruno, Claudio published the artcileThe chemosensitizing agent lubeluzole binds calmodulin and inhibits Ca²⁺/calmodulin-dependent kinase II, SDS of cas: 140-28-3, the publication is European Journal of Medicinal Chemistry (2016), 36-45, database is CAplus and MEDLINE.

An affinity capillary electrophoresis (ACE) method to estimate apparent dissociation constants between bovine brain calmodulin (CaM) and nonpeptidic ligands was developed. The method was validated reproducing the dissociation constants of a number of well-known CaM ligands. In particular, the potent antagonist 125-C9 was ad hoc synthesized through an improved synthetic procedure. The ACE method was successfully applied to verify CaM affinity for lubeluzole, a well-known neuroprotective agent recently proved useful to potentiate the activity of anticancer drugs. Lubeluzole was slightly less potent than 125-C9 (K_d = 2.9¡À0.7 and 0.47¡À0.06 ¦ÌM, resp.) and displayed Ca²⁺/calmodulin-dependent kinase II (CaMKII) inhibition (IC₅₀ = 40¡À1 ¦ÌM). Possible binding modes of lubeluzole to CaM were explored by docking studies based on the x-ray crystal structures of several trifluoperazine-CaM complexes. An estimated dissociation constant in good agreement with the exptl. one was found and the main aminoacidic residues and interactions contributing to complex formation were highlighted. The possibility that interference with Ca²⁺ pathways may contribute to the previously observed chemosensitizing effects of lubeluzole on human ovarian adenocarcinoma and lung carcinoma cells are discussed.

European Journal of Medicinal Chemistry published new progress about 140-28-3. 140-28-3 belongs to catalysis-chemistry, auxiliary class Benzenes, name is N1,N2-Dibenzylethane-1,2-diamine, and the molecular formula is C16H20N2, SDS of cas: 140-28-3.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Stolarova, Monika published the artcileTwo novel coordination polymers in the family of lanthanide complexes with o-phenylenedioxydiacetato as ligand, Synthetic Route of 5411-14-3, the publication is Polyhedron (2015), 149-155, database is CAplus.

Two novel coordination polymers [Ce(PDOA)(NO₃)(H₂O)₂]_n (1) and {[Ce(PDOA)(NO₃)(H₂O)₃]¡¤H₂O}_n (2) (PDOA = o-phenylenedioxydiacetato) have been prepared using hydrothermal conditions and have been structurally characterized. In both crystal structures 1 and 2 the Ce(III) atoms are decacoordinated by oxygen atoms from PDOA ligands with chelating and bridging functions, chelating nitrato ligands and aqua ligands. While in 1 the PDOA ligand presents a hexadentate coordination mode, in 2 it is coordinated in a pentadentate manner; this difference leads to different types of one-dimensional structural motifs: in 2 there are zig-zag chains of the -Ce-O-C-O-Ce- type with syn-anti carboxylate bridges and in 1 these chains are addnl. interlinked by further syn-anti carboxylate bridges leading to a strip- or ribbon-like arrangement formed of {Ce₃} fused triangles. The endothermic dehydration of 1 within the temperature range 69-199 ¡ãC is at least a two-step process as suggested by TG and DTA methods. A variable temperature (2-300 K) magnetic study reveals Curie-Weiss behavior for 1 with ¦È = -35.5 K observed above 50 K. The origin of the observed behavior is discussed.

Polyhedron published new progress about 5411-14-3. 5411-14-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2,2-(1,2-Phenylenebis(oxy))diacetic acid, and the molecular formula is C11H16BNO3, Synthetic Route of 5411-14-3.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Stolarova, Monika published the artcile¦Ï-Phenylenedioxydiacetate complexes of Gd(III) and Ce(III): syntheses, crystal structures, and magnetic properties, Recommanded Product: 2,2-(1,2-Phenylenebis(oxy))diacetic acid, the publication is Journal of Coordination Chemistry (2014), 67(6), 1046-1060, database is CAplus.

{[Ln₂(PDOA)₃(H₂O)₆]?2H₂O}_n (Ln = Gd, 1; Ln = Ce, 2; H₂PDOA = ¦Ï-phenylenedioxydiacetic acid) has been synthesized and characterized by chem. analyses, IR spectroscopy, and thermal analyses. Single-crystal X-ray structure analyses revealed that both 1 and 2 are polymeric and built up of a ladder-like arrangement of Ln(III) ions linked by short syn-anti carboxylate bridges and long bridges (legs of the ladder) formed by a second crystallog. independent PDOA. Ln(III) in both 1 and 2 is nine-coordinate with an O₉ donor set formed by one chelating/bridging and one bridging PDOA, and an addnl. three waters. In the asym. unit, there is one crystallog. independent water of crystallization, which is involved in a rich system of hydrogen bonds of the O-H¡¤¡¤¡¤O type. The identities of the bulk and single crystal phases were corroborated by powder X-ray diffraction. Variable temperature (2-300 K) magnetic studies indicate the presence of only weak antiferromagnetic interactions between pairs of paramagnetic Ln(III) ions with J/hc = -0.004 and -0.13 cm^-1, for 1 and 2.

Journal of Coordination Chemistry published new progress about 5411-14-3. 5411-14-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2,2-(1,2-Phenylenebis(oxy))diacetic acid, and the molecular formula is C10H7NO3, Recommanded Product: 2,2-(1,2-Phenylenebis(oxy))diacetic acid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Schwalm, Cristiane S. published the artcileMetal halide hydrates as Lewis acid catalysts for the conjugated Friedel-Crafts reactions of indoles and activated olefins, Safety of 1,2-Dimethoxy-4-(2-nitrovinyl)benzene, the publication is Journal of the Brazilian Chemical Society (2011), 22(4), 623-636, database is CAplus.

Metal halide hydrates, such as SnCl₂.2H₂O, MnCl₂.4H₂O, SrCl₂.6H₂O, CrCl₃.6H₂O, CoCl₂.6H₂O, and CeCl₃.7H₂O, were investigated as mild Lewis acid catalysts for the conjugate Friedel-Crafts reaction between indoles and activated olefins. The reactions were carried out with aliphatic unsaturated ketones over a period of days at room temperature, while chalcones reacted only under reflux conditions. The reactions with nitrostyrenes were either performed in solvent or under solventless conditions. In all cases reasonable to good yields were obtained.

Journal of the Brazilian Chemical Society published new progress about 4230-93-7. 4230-93-7 belongs to catalysis-chemistry, auxiliary class Alkenyl,Nitro Compound,Benzene,Ether, name is 1,2-Dimethoxy-4-(2-nitrovinyl)benzene, and the molecular formula is C11H10N4, Safety of 1,2-Dimethoxy-4-(2-nitrovinyl)benzene.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia