5780-66-5Relevant articles and documents
2,3,5,6-Tetra(pyrazin-2-yl)pyrazine: a novel bis-bidentate, bis-tridentate chelator
Ligiero, Carolina B.P.,Visentin, Lorenzo C.,Giacomini, Rosana,Filgueiras, Carlos A.L.,Miranda, Paulo C.M.L.
, p. 4030 - 4032 (2009)
Novel 10-nitrogen ligand, 2,3,5,6-tetra(pyrazin-2-yl)pyrazine, has been synthesized in four steps. This compound shows different conformations and the crystal structure of one of them has been established. This structure is sustained by non-classical H-bonds and π···π interactions among heteroaromatic rings.
An Engineered Alcohol Oxidase for the Oxidation of Primary Alcohols
Heath, Rachel S.,Birmingham, William R.,Thompson, Matthew P.,Taglieber, Andreas,Daviet, Laurent,Turner, Nicholas J.
, p. 276 - 281 (2019/01/04)
Structure-guided directed evolution of choline oxidase has been carried out by using the oxidation of hexan-1-ol to hexanal as the target reaction. A six-amino-acid variant was identified with a 20-fold increased kcat compared to that of the wild-type enzyme. This variant enabled the oxidation of 10 mm hexanol to hexanal in less than 24 h with 100 % conversion. Furthermore, this variant showed a marked increase in thermostability with a corresponding increase in Tm of 20 °C. Improved solvent tolerance was demonstrated with organic solvents including ethyl acetate, heptane and cyclohexane, thereby enabling improved conversions to the aldehyde by up to 30 % above conversion for the solvent-free system. Despite the evolution of choline oxidase towards hexan-1-ol, this new variant also showed increased specific activities (by up to 100-fold) for around 50 primary aliphatic, unsaturated, branched, cyclic, benzylic and halogenated alcohols.
2 - Trinitroazetidine methyl pyrazine compounds (by machine translation)
-
Paragraph 0022; 0039-0041, (2019/02/04)
The invention discloses a 2 - trinitroazetidine methyl pyrazine compound, such as the formula (I) as shown: This invention is used mainly in the field of explosives. (by machine translation)
The effects of thermal treatment of ZnO–ZnCr2O4 catalyst on the particle size and product selectivity in dehydrocyclization of crude glycerol and ethylenediamine
Sarkari, Reema,Krishna, Vankudoth,Sudhakar, Medak,Rao, Tumula Venkateshwar,Padmasri, Aytam Hari,Srinivas, Darbha,Venugopal, Akula
, p. 602 - 609 (2016/10/18)
The ZnO–ZnCr2O4 (Zn–Cr–O) sample obtained by decomposition of Zn-Cr hydrotalcite precursor was subjected to the thermal treatment at different temperatures and the physico-chemical properties of the Zn–Cr–O system were compared with
AMINONITRILES AS KYNURENINE PATHWAY INHIBITORS
-
Page/Page column 89; 90, (2014/09/29)
The present application provides novel kynurenine pathway inhibitors and pharmaceutically acceptable salts and prodrugs thereof. Also provided are methods for preparing these compounds. These compounds are useful in regulating the kynurenine pathway and the activity of indoleamine 2,3-dioxygenase and/or tryptophan 2,3-dioxygenase by administering a therapeutically effective amount of one or more of the compounds of formula (I) to a patient. By doing so, these compounds are effective in treating conditions associated with the dysregulation of the kynurenine pathway. A variety of conditions can be treated using these compounds and include diseases which are characterized by immunosuppression, abnormal cellular proliferation and/or inflammation. In one embodiment, the disease is cancer. In another embodiment, the disease is a viral infection. In a further embodiment, the disease is depression.
Tuning of the properties of transition-metal bispidine complexes by variation of the basicity of the aromatic donor groups
Comba, Peter,Morgen, Michael,Wadepohl, Hubert
, p. 6481 - 6501 (2013/07/19)
Bispidines (3,7-diazabicyclo[3.3.1]nonanes) as very rigid and highly preorganized ligands find broad application in the field of coordination chemistry, and the redox potentials of their transition-metal complexes are of importance in oxidation reactions by high-valent iron complexes, aziridination catalyzed by copper complexes, and imaging by 64Cu positron emission tomography tracers. Here, we show that the redox potentials and stability constants of the copper(II) complexes of 15 tetradentate bispidines can be varied by substitution of the pyridine rings (variation of the redox potential over ca. 450 mV and of the complex stability over approximately 10 log units). It is also shown that these variations are predictable by the pKa values of the pyridine groups as well as by the Hammett parameters of the substituents, and the density functional theory based energy decomposition analysis also allows one to accurately predict the redox potentials and concomitant complex stability. It is shown that the main contribution emerges from the electrostatic interaction energy, and the partial charges of the pyridine donor groups therefore also correlate with the redox potentials.
A general method for the enantioselective synthesis of α-chiral heterocycles
Le, Phong Q.,Nguyen, Thien S.,May, Jeremy A.
supporting information, p. 6104 - 6107 (2013/02/23)
The enantioselective formation of stereocenters proximal to unprotected heterocycles has been accomplished. Thus, vinyl boronic acids are added to heterocycle-appended enones via a modified-BINOL catalyst. Catalyst design was key to enable a general reaction. High yields and useful er's are observed for a host of common heteroaryls.
Vapor phase synthesis of methylpyrazine using aqueous glycerol and ethylenediamine over ZnCr2O4 catalyst: Elucidation of reaction mechanism
Sarkari, Reema,Anjaneyulu, Chatla,Krishna, Vankudoth,Kishore, Ramineni,Sudhakar, Medak,Venugopal, Akula
experimental part, p. 1067 - 1070 (2012/01/15)
A novel method has been developed for the synthesis of methylpyrazine (MP) by using aqueous glycerol and ethylenediamine (EDA) over Zn-Cr catalyst derived from hydrotalcite precursors. The X-ray diffraction analysis of the oven-dried Zn-Cr samples synthesized at various pH ranging from 7 to 11 showed hydrotalcite phase whereas the calcined catalysts displayed ZnO and ZnCr2O 4 phases. The cyclisation activity of Zn-Cr catalyst prepared at pH ～ 9 demonstrated 99.4% conversion of EDA and 94% of glycerol with ～ 72% selectivity to MP at a reaction temperature of 400 °C. This process demonstrates direct utilization of bio-glycerol for the synthesis of MP.
Palladium-catalyzed acetoxylation of sp3 C-H bonds using molecular oxygen
Jiang, Huanfeng,Chen, Huoji,Wang, Azhong,Liu, Xiaohang
supporting information; experimental part, p. 7259 - 7261 (2011/01/07)
Molecular oxygen as oxidant to promote palladium-catalyzed acetoxylation of sp3 C-H bonds to afford α-oxygenated products is reported.
Novel Isoxazoles and Methods of Use Thereof
-
Page/Page column 19-20, (2009/12/24)
The invention relates to isoxazole derivatives, compositions comprising such compounds, and methods of preventing or treating conditions and disorders using such compounds and compositions.
