- Bipyridine derivative with substituted multiple functional groups and method for preparing bipyridine derivative
-
The invention belongs to the field of organic chemistry, and particularly relates to a method for preparing a bipyridine derivative with substituted multiple functional groups. The method includes mixing halogenated pyridine derivatives and activated copper powder with one another to obtain first mixtures, carrying out reflux cooling, adding ammonia water into the first mixtures to obtain second mixtures, filtering, abstracting and extracting the second mixtures, combining organic phases with one another, drying the organic phases, and carrying out chromatographic purification by the aid of silica columns to obtain the bipyridine derivative (shown as a formula I) with the substituted multiple functional groups; dissolving products shown as the formula I in methanol, sequentially adding ferric trichloride and activated carbon into the methanol to obtain third mixtures and carrying out heating reflux for 10 minutes; adding hydrazine hydrate into the third mixtures to obtain fourth mixtures, carrying out reflux, filtering the fourth mixtures while the fourth mixtures are hot, washing the fourth mixtures, combining organic phases with one another, drying the organic phases and carrying out chromatographic purification by the aid of silica columns to obtain products shown as a formula II. The method has the advantages that coupling reaction is carried out under the catalytic effect of copper, and accordingly the bipyridine derivative with the substituted multiple functional groups can be efficiently synthesized; the method is simple and is important supplement to existing pyridine coupling reaction, and the obtained bipyridine derivative with substituted electron withdrawing groups further can be converted into a bipyridine derivative with substituted electron donating group amino.
- -
-
Paragraph 0033; 0034; 0035; 0036
(2017/09/18)
-
- Photoswitchable Magnetic Resonance Imaging Contrast by Improved Light-Driven Coordination-Induced Spin State Switch
-
We present a fully reversible and highly efficient on-off photoswitching of magnetic resonance imaging (MRI) contrast with green (500 nm) and violet-blue (435 nm) light. The contrast change is based on intramolecular light-driven coordination-induced spin state switch (LD-CISSS), performed with azopyridine-substituted Ni-porphyrins. The relaxation time of the solvent protons in 3 mM solutions of the azoporphyrins in DMSO was switched between 3.5 and 1.7 s. The relaxivity of the contrast agent changes by a factor of 6.7. No fatigue or side reaction was observed, even after >100 000 switching cycles in air at room temperature. Electron-donating substituents at the pyridine improve the LD-CISSS in two ways: better photostationary states are achieved, and intramolecular binding is enhanced.
- Dommaschk, Marcel,Peters, Morten,Gutzeit, Florian,Schütt, Christian,N?ther, Christian,S?nnichsen, Frank D.,Tiwari, Sanjay,Riedel, Christian,Boretius, Susann,Herges, Rainer
-
supporting information
p. 7552 - 7555
(2015/07/02)
-
- Manganese salen complexes with acid-base catalytic auxiliary: Functional mimetics of catalase
-
Antioxidant therapies have been considered for a wide variety of disorders associated with oxidative stress, and synthetic catalytic scavengers of reactive oxygen species would be clinically superior to stoichiometric ones. Among them, salen-manganese complexes (Mn(Salen)) seem promising, because they exhibit dual functions, i.e. superoxide dismutase- and catalase-mimetic activities. We have been developing enzyme-mimetic Mn(Salen) complexes bearing a functional group that enhances their catalytic activity. Here, we describe the design and synthesis of novel Mn(Salen) complexes with general acid-base catalytic functionality, inspired by the reaction mechanism of catalase. As expected, these Mn(Salen) complexes showed superior catalase-like activity and selectivity, while retaining moderate SOD-like activity. An unsubstituted pyridyl group worked well as a functionality to promote catalase-like activity. The introduced functionality did not alter the redox potential suggesting that the auxiliary-modified complex acted as an acid-base catalyst analogous to catalase. We believe that our approach provides a new design principle for sophisticated catalyst design. Further, the compounds described here appear to be good candidates for use in antioxidant therapy.
- Noritake, Yukinobu,Umezawa, Naoki,Kato, Nobuki,Higuchi, Tsunehiko
-
p. 3653 - 3662
(2013/05/09)
-
- Synthesis of novel dipyrido-1,4-thiazines
-
An efficient synthesis of novel type of dipyrido-1,4-thiazine (4) was elaborated in the reactions of two pairs of 3,4-disubstituted pyridines in DMF. The reactions proceeded through the S→N type of the Smiles rearrangement of the resulting 4,4′-dipyridiny
- Morak-Mlodawska, Beata,Pluta, Krystian
-
p. 1347 - 1361
(2008/03/13)
-
- Synthesis and structure of dipyrido-1,4-dithiins
-
Synthesis, properties and reactions of two isomeric dipyrido-1,4-dithiins of the C2h and C2v symmetry are described. Their structure determination and identification are based on spectroscopic methods (1H and 13C NMR, HETCOR, gHMBC and MS), physical properties (mp and Rf), the 1,4-dithiin ring opening reactions and finally X-Ray analysis. A very unusual type of the Smiles rearrangement (S→S, the pyridyl group migrates from one sulfur atom to another) during the 1,4-dithiin ring opening with sodium methanethiolate enabling isomerization of dithiin with the C2h symmetry to dithiin with the C2v symmetry is found.
- Morak, Beata,Pluta, Krystian,Suwinska, Kinga,Grymel, Miroslawa,Besnard, Celine,Schiltz, Marc,Kloc, Christian,Siegrist, Theo
-
p. 2619 - 2634
(2007/10/03)
-
- Preparation of nitropyridines by nitration of pyridines with nitric acid
-
Preparation of nitropyridines by nitration of pyridines with nitric acid was discussed. Trifluoroacetic anhydride was chilled in an ice bath and the pyridine or substituted pyridines were slowly added and stirred at chilled conditions for 2 h. Relative amounts of the reactants were required for the nitration of pyridine were characterized by 1H and Nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. It was observed that the yields of β-nitropyridines obtained using the standard protocol were generally higher than those obtained using N2O3.
- Katritzky, Alan R.,Scriven, Eric F. V.,Majumder, Suman,Akhmedova, Rena G.,Vakulenko, Anatoliy V.,Akhmedov, Novraz G.,Murugan, Ramiah,Abboud, Khalil A.
-
p. 538 - 541
(2007/10/03)
-