259807-95-9Relevant academic research and scientific papers
Conformational study of an artificial metal-dependent regulation site for use in designer proteins
Oheix, Emmanuel,Spencer, Neil,Gethings, Lee A.,Peacock, Anna F. A.
, p. 1370 - 1383 (2013)
This report describes the dimerisation of glutathione, and by extension, other cysteine-containing peptides or protein fragments, with a 5, 5'-disubstituted-2, 2'-bipyridine or 6, 6''-disubstituted-2, 2':6',2''-terpyridine unit. The resulting bipy-GS2 and terpy-GS 2 were investigated as potential metal ion dependent switches in aqueous solution, and were found to predominantly adopt the transoid conformation at physiological pH. Metal complexation with CuII and ZnII at this pH has been studied by UV/Vis, CD, NMR and ion-mobility mass spectrometry. ZnII titrations are consistent with the formation of a 1:1 ZnII:terpy-GS2 complex at pH 7.4, but bipy-GS2 was shown to form both 1:1 and 1:2 complexes with the former being predominant under dilute micromolar conditions. Formation constants for the resulting 1:1 complexes were determined to be log KM 6.86 (bipy-GS2) and 6.22 (terpy-GS2), consistent with a higher affinity for the unconstrained bipyridine, compared to the strained terpyridine. CuII coordination involves the initial formation of 1:1 complexes, followed by 1.5Cu:1bipy-GS2 and 2Cu:1terpy-GS2 complexes at micromolar concentrations. Binding constants for formation of the 1:1 complexes (log KM 12.5 (bipy-GS2); 8.04 and 7.14 (terpy-GS2)) indicate a higher affinity for CuII than ZnII. Finally, ion-mobility MS studies detected the free ligands in their protonated form, and were consistent with the formation of two different Cu adducts with different conformations in the gas-phase. We illustrate that the bipyridine and terpyridine dimerisation units can behave like conformational switches in response to Cu/Zn complexation, and propose that in future these can be employed in synthetic biology with larger peptide or protein fragments, to control large scale folding and related biological function. Copyright
Synthesis and physico-chemical properties of homoleptic copper(I) complexes with asymmetric ligands as a dssc dye
Hatano, Mayuka,Inomata, Tomohiko,Kawai, Yuya,Kitagawa, Takuma,Masuda, Hideki,Matsunaga, Ayaka,Ozawa, Tomohiro,Wasada-Tsutsui, Yuko
, (2021/11/27)
To develop low-cost and efficient dye-sensitized solar cells (DSSCs), we designed and prepared three homoleptic Cu(I) complexes with asymmetric ligands, M1, M2, and Y3, which have the advantages of heteroleptic-type complexes and compensate for their synthetic challenges. The three copper(I) complexes were characterized by elemental analysis, UV-vis absorption spectroscopy, and electrochemical measurements. Their absorption spectra and orbital energies were evaluated and are discussed in the context of TD-DFT calculations. The complexes have high VOC values (0.48, 0.60, and 0.66 V for M1, M2, and Y3, respectively) which are similar to previously reported copper(I) dyes with symmetric ligands, although their energy conversion efficiencies are relatively low (0.17, 0.64, and 2.66%, respectively).
HETEROCYCLIC COMPOUNDS AND METHODS OF USE
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Paragraph 000215; 000217, (2020/02/06)
The present invention discloses compounds useful in treatment of conditions associated with excessive activity of transforming growth factor beta (TGF-β), particularly type 1 or activin-like kinase 5 (ALK 5). Specifically the present invention discloses compound of formula (I) which exhibit inhibitory activity against ALK 5. Method of treating conditions associated with excessive activity (ALK 5) with such compound is disclosed. Uses thereof, pharmaceutical composition, and kits are also disclosed.
MACROCYCLIC AZOLOPYRIDINE DERIVATIVES AS EED AND PRC2 MODULATORS
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Paragraph 0907, (2020/10/09)
The invention relates to modulators of Embryonic Ectoderm Development (EED) and/or Polycomb Repressive Complex 2 (PRC2) useful in the treatment of disorders and diseases associated with EEC and PRC2, being macrocyclic azolopyridine derivatives and compositions thereof of Formula (I), or a pharmaceutically acceptable salt, prodrug, solvate, hydrate, enantiomer, isomer, or tautomer thereof, wherein X1, X2, X3, A1, A2, Y, R1, R2, R3, and R4 are as described herein.
Optically Active Helical Lanthanide Complexes: Storable Chiral Lewis Acidic Catalysts for Enantioselective Diels–Alder Reaction of Siloxydienes
Harada, Shinji,Nakashima, Saki,Nishida, Atsushi,Oishi, Wakana,Sekino, Shihori
supporting information, (2020/02/05)
Lanthanide triflates and a series of hexadentate chiral ligand complexes were synthesized. X-ray-quality crystals were obtained from mixtures of the lanthanide complexes, which were helical in shape. The complexes showed Lewis acidity and catalyzed the enantioselective Diels–Alder reaction of electron-rich siloxydienes. The complexes were stable enough to be stored at ambient temperature on a laboratory bench and retained their Lewis acidity even after a month.
Photocatalytic CO2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO2, CO, or Proton
Shimoda, Tomoe,Morishima, Takeshi,Kodama, Koichi,Hirose, Takuji,Polyansky, Dmitry E.,Manbeck, Gerald F.,Muckerman, James T.,Fujita, Etsuko
, p. 5486 - 5498 (2018/05/17)
The cobalt complexes CoIIL1(PF6)2 (1; L1 = 2,6-bis[2-(2,2′-bipyridin-6′-yl)ethyl]pyridine) and CoIIL2(PF6)2 (2; L2 = 2,6-bis[2-(4-methoxy-2,2′-bipyridin-6′-yl)ethyl]pyridine) were synthesized and used for photocatalytic CO2 reduction in acetonitrile. X-ray structures of complexes 1 and 2 reveal distorted trigonal-bipyramidal geometries with all nitrogen atoms of the ligand coordinated to the Co(II) center, in contrast to the common six-coordinate cobalt complexes with pentadentate polypyridine ligands, where a monodentate solvent completes the coordination sphere. Under electrochemical conditions, the catalytic current for CO2 reduction was observed near the Co(I/0) redox couple for both complexes 1 and 2 at E1/2 = -1.77 and -1.85 V versus Ag/AgNO3 (or -1.86 and -1.94 V vs Fc+/0), respectively. Under photochemical conditions with 2 as the catalyst, [Ru(bpy)3]2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor, CO and H2 were produced under visible-light irradiation, despite the endergonic reduction of Co(I) to Co(0) by the photogenerated [Ru(bpy)3]+. However, bulk electrolysis in a wet CH3CN solution resulted in the generation of formate as the major product, indicating the facile production of Co(0) and [Co-H]n+ (n = 1 and 0) under electrochemical conditions. The one-electron-reduced complex 2 reacts with CO to produce [Co0L2(CO)] with νCO = 1894 cm-1 together with [CoIIL2]2+ through a disproportionation reaction in acetonitrile, based on the spectroscopic and electrochemical data. Electrochemistry and time-resolved UV-vis spectroscopy indicate a slow CO binding rate with the [CoIL2]+ species, consistent with density functional theory calculations with CoL1 complexes, which predict a large structural change from trigonal-bipyramidal to distorted tetragonal geometry. The reduction of CO2 is much slower than the photochemical formation of [Ru(bpy)3]+ because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for the reduction to Co(0) by the photoproduced [Ru(bpy)3]+.
Ruthenium PNN(O) Complexes: Cooperative Reactivity and Application as Catalysts for Acceptorless Dehydrogenative Coupling Reactions
De Boer, Sandra Y.,Korstanje, Ties J.,La Rooij, Stefan R.,Kox, Rogier,Reek, Joost N. H.,Van Der Vlugt, Jarl Ivar
, p. 1541 - 1549 (2017/04/28)
The novel tridentate PNNOH pincer ligand LH features a reactive 2-hydroxypyridine functionality as well as a bipyridyl-methylphosphine skeleton for meridional coordination. This proton-responsive ligand coordinates in a straightforward manner to RuCl(CO)(H)(PPh3)3 to generate complex 1. The methoxy-protected analogue LMe was also coordinated to Ru(II) for comparison. Both species have been crystallographically characterized. Site-selective deprotonation of the 2-hydroxypyridine functionality to give 1′ was achieved using both mild (DBU) and strong bases (KOtBu and KHMDS), with no sign of involvement of the phosphinomethyl side arm that was previously established as the reactive fragment. Complex 1′ is catalytically active in the dehydrogenation of formic acid to generate CO-free hydrogen in three consecutive runs as well as for the dehydrogenative coupling of alcohols, giving high conversions to different esters and outperforming structurally related PNN ligands lacking the NOH fragment. DFT calculations suggest more favorable release of H2 through reversible reactivity of the hydroxypyridine functionality relative to the phosphinomethyl side arm.
Bipyridine ligand ruthenium complex is carried and its preparation method and application (by machine translation)
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Paragraph 0045; 0046, (2017/04/28)
The invention relates to a novel bipyridine is carried ligand ruthenium complex and its preparation method and in the ester compound hydrogenation is the application of the alcohol compound in the reaction. The use of the bipyridine ligand ruthenium complex catalytic hydrogenation is carried ester compound alcohol compound method is characterized in that: in order to ester compound material in an amount of 0.001 - 0.3 μM % bipyridyl is carried ligand ruthenium complex as catalyst, adding esters compound material in an amount of 1 - 10mol % alkali, in the 25 - 100 °C and 1 - 10MPa hydrogen pressure catalytic hydrogenation under the conditions of ester compound corresponding alcohol compound. The invention of the bipyridine ligand ruthenium complex is carried is convenient to prepare, stable structure, in the ester compound in hydrogenation reaction exhibits excellent catalytic activity. This invention has overcome the ester compound or a non-homogeneous phase catalytic hydrogenation system requires high-temperature high-pressure reaction conditions and high defects of the catalyst amount, catalyst consumption is small, mild reaction conditions, the reaction selectivity is good, improves the economy and the safety of the production system. (by machine translation)
Ruthenium complexes of tetradentate bipyridine ligands: Highly efficient catalysts for the hydrogenation of carboxylic esters and lactones
Li, Wei,Xie, Jian-Hua,Yuan, Ming-Lei,Zhou, Qi-Lin
supporting information, p. 4081 - 4085 (2014/10/15)
A new type of readily available, air-stable ruthenium complex of tetradentate bipyridine ligands has been developed. These complexes displayed exceptional efficiency for the hydrogenation of aromatic and aliphatic carboxylic esters and lactones at as low as 10 ppm catalyst loading under very mild conditions. the Partner Organisations 2014.
Catalytic hydrosilylation of alkenes by iron complexes containing terpyridine derivatives as ancillary ligands
Kamata, Kouji,Suzuki, Atsuko,Nakai, Yuta,Nakazawa, Hiroshi
, p. 3825 - 3828 (2012/07/02)
Iron complexes formulated as Fe(terpy)X2 (terpy = 2,2′:6′,2 -terpyridine derivatives; X = Cl, Br) were prepared and their catalytic activities for hydrosilylation of olefin with hydrosilane were examined. Although Fe(terpy)X2 did not
