609-71-2Relevant academic research and scientific papers
Synthesis, characterization and electrochemical investigations of mixed-ligand copper(II)-organic supramolecular frameworks
Singh, Sandeep K.,Srivastava, Ashish Kumar,Srivastava, Krishna,Banerjee, Rahul,Prasad, Jagdish
, p. 549 - 557 (2017)
Two mixed-ligand copper(II)-organic coordination compounds with 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2bpy) as a primary ligand while aliphatic malonate (Hmal) and aromatic 2-hydroxynicotinate (2-OHNA) as secondary ligands, were synthesized. These complexes are formulated as: [Cu(Hmal)(5,5′-Me2bpy)(H2O)](ClO4) 1 and [Cu2(2-OHNA)2(5,5′-Me2bpy)2(NO3)](NO3) 2. These two complexes were structurally characterized by single crystal X-ray diffraction analysis. Characterization was further supported by powder X-ray diffraction analysis, elemental analyses, FT-IR, FAB-MASS and TGA, DSC studies. Cyclic voltammetric and UV-visible spectral studies of these two complexes have also been done. The electrochemical studies of complex 1 in DMSO and DMF have shown that this complex undergoes quasi-reversible diffusion-controlled one-electron transfer reaction without any chemical complication while complex 2 in DMSO undergoes quasi-reversible diffusion-controlled one electron transfer reaction, following EC mechanism. The electrochemical behaviour of complex 2 in DMF is complicated probably due to presence of more than one species in solution phase.
Solid-state identity of 2-hydroxynicotinic acid and its polymorphism
Long, Sihui,Zhou, Panpan,Theiss, Kathryn L.,Siegler, Maxime A.,Li, Tonglei
, p. 5195 - 5205 (2015)
2-Hydroxynicotinic acid (2-HNA), a derivative of nicotinic acid, was found to exist in four polymorphs. In the solid state, 2-HNA is actually present as its tautomer, 2-oxo-1,2-dihydro-3-pyridinecarboxylic acid (2-ODHPCA). The polymorphism stems from distinctive packing arrangements of the molecules, and the formation of the distinct polymorphs can be affected by using various acidic additives. The thermal behaviors of the four polymorphs indicate that form I is the most stable at elevated temperature, form II converts into form I during heating, and forms III and IV transform into form II when heated. Theoretical studies showed that 2-ODHPCA is more energetically favored than 2-HNA. Condensed Fukui functions and the dual descriptor were used jointly to examine the local preference of hydrogen bonding in the crystal. Lattice energy calculations were conducted to further evaluate energetic properties of the system.
Preparation method of 2-chloronicotinic acid
-
Paragraph 0023-0028, (2021/06/26)
The invention relates to a preparation method of 2-chloronicotinic acid. 2-chloronicotinic acid as a product is obtained by two steps of reactions of carboxylation and chlorination of 2-hydroxypyridine in an organic solvent at a certain temperature. The method provided by the invention has the advantages of more raw material sources, obvious cost advantage, safer and more convenient preparation method, high total yield and less three wastes, especially can avoid the use of phosphine oxychloride or triphosgene, and is beneficial to industrialization.
A tautomeric ligand enables directed C-H hydroxylation with molecular oxygen
Li, Zhen,Wang, Zhen,Chekshin, Nikita,Qian, Shaoqun,Qiao, Jennifer X.,Cheng, Peter T.,Yeung, Kap-Sun,Ewing, William R.,Yu, Jin-Quan
, p. 1452 - 1457 (2021/06/30)
Hydroxylation of aryl carbon-hydrogen bonds with transition metal catalysts has proven challenging when oxygen is used as the oxidant. Here, we report a palladium complex bearing a bidentate pyridine/ pyridone ligand that efficiently catalyzes this reaction at ring positions adjacent to carboxylic acids. Infrared, x-ray, and computational analysis support a possible role of ligand tautomerization from monoanionic (L,X) to neutral (L,L) coordination in the catalytic cycle of aerobic carbon-hydrogen hydroxylation reaction. The conventional site selectivity dictated by heterocycles is overturned by this catalyst, thus allowing late-stage modification of compounds of pharmaceutical interest at previously inaccessible sites.
Halogen–metal exchange on bromoheterocyclics with substituents containing an acidic proton via formation of a magnesium intermediate
Tian, Qingqiang,Shang, Suqin,Wang, Huajun,Shi, Guoqiang,Li, Zhiyao,Yuan, Jianyong
supporting information, (2017/12/05)
A selective and practical bromine–metal exchange on bromoheterocyclics bearing substituents with an acidic proton under non-cryogenic conditions was developed by a simple modification of an existing protocol. Our protocol of using a combination of i-PrMgCl and n-BuLi has not only solved the problem of intermolecular quenching that often occurred when using alkyl lithium alone as the reagent for halogen–lithium exchange, but also offered a highly selective method for performing bromo–metal exchange on dibrominated arene compounds through chelation effect.
PHARMACEUTICAL COMPOSITION COMPRISING PYRIDONE DERIVATIVES
-
Paragraph 0403, (2013/12/04)
A pyridone derivative compound and a pharmaceutically acceptable salt, isomer, solvate or hydrate thereof, and a preventive or therapeutic pharmaceutical composition for cognitive disorders that includes the pyridone derivative compound or a pharmaceutically acceptable salt, isomer, solvate or hydrate thereof.
PHARMACEUTICAL COMPOSITION COMPRISING PYRIDONE DERIVATIVES
-
Page/Page column 72, (2012/08/08)
A pyridone derivative compound and a pharmaceutically acceptable salt, isomer, solvate or hydrate thereof, and a preventive or therapeutic pharmaceutical composition for cognitive disorders that includes the pyridone derivative compound or a pharmaceutically acceptable salt, isomer, solvate or hydrate thereof.
A simple and practical copper-catalyzed approach to substituted phenols from aryl halides by using water as the solvent
Yang, Daoshan,Fu, Hua
supporting information; experimental part, p. 2366 - 2370 (2010/06/15)
Water surprise! A simple and practical copper-catalyzed approach to substituted phenols by hydroxylation of aryl halides has been developed by using environmentally benign water as the solvent (see scheme). The method proceeds under mild conditions and is tolerant towards various functional groups in the substrates.
Kinetics of oxidation of heterocyclic compounds by quinolinium dichromate
Saunte, Hauzachin,Chaubey, Girija S.,Mahanti, Mahendra K.
experimental part, p. 291 - 298 (2012/04/10)
Quinolinium dichromate in sulfuric acid oxidized heterocyclic aldehydes (to the corresponding acids) and heterocyclic carboxylic acids (to the corresponding hydroxy-substituted acids) in acetic acidwater medium (vol. ratio, v(water)/v(acetic acid) = 50:50). The kinetic results supported a mechanistic pathway proceeding via a rate-determining decomposition of the chromate ester.
Synthesis and biological evaluation of 2,4,6-functionalized derivatives of pyrido[2,3-d]pyrimidines as cytotoxic agents and apoptosis inducers
Sanmartin, Carmen,Dominguez, Maria Victoria,Cordeu, Lucia,Cubedo, Elena,Garcia-Foncillas, Jesus,Font, Maria,Palop, Juan Antonio
, p. 28 - 41 (2008/09/21)
In the search for new derivatives with anticancer activity that are able to induce a selective proapoptotic mechanism in cancer cells, we have designed, synthesized, and evaluated a series of new 2-(alkylsulfanyl)-N-alkylpyrido[2,3- d]pyrimidine-4-amine derivatives as cytotoxic and apoptosis inducers. The potential antitumor activity of the compounds was evaluated in vitro by examining their cytotoxic effects against human breast, colon, and bladder cancer-cell lines. The IC50 values of the compounds that showed cytotoxic activity were calculated. The cytotoxic compounds were then tested for their ability to induce caspase-3 activation and nuclear-chromatin degradation. Some compounds, such as 6c, 6d, 6e, 6j, 6o, and 6p, show significant in-vitro cytotoxicity in at least two of the three tested cell lines, induced apoptosis, and also produced a rapid dose-dependent increase in the caspase-3 level in some of the cell lines tested. In order to test the selectivity of the compounds, two non-tumoral human cell lines were used. Several compounds of the did not show cytotoxicity in these cell lines.
