3685-22-1Relevant articles and documents
PNO ligand containing planar chiral ferrocene and axial chiral diphenol and application thereof
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Paragraph 0128-0131, (2021/06/23)
The invention discloses a PNO ligand containing planar chiral ferrocene and axially chiral diphenol and application of the PNO ligand. The PNO ligand containing planar chiral ferrocene and axially chiral diphenol is shown in any one of general formulas (I)-(IV). Or a PNO ligand containing planar chiral ferrocene and axial chiral diphenol as shown in any one of general formulas (V)-(VIII); compared with a previously reported tridentate ligand, the PNO ligand containing the planar chiral ferrocene and the axial chiral diphenol not only has good stability and easiness in synthesis, but also has planar chirality and axial chirality and has a good chiral environment, so that not only is excellent selectivity to a substrate ensured, but also the catalytic activity of a catalyst and the application range of the substrate are further improved. The chiral raw materials used in the invention are commercial bulk products, and the ligand synthesis route is simpler, so that large-scale production can be well carried out, and the method has a huge commercial application prospect.
A Molecular Torsion Balance Study: A Nearby Anionic Group Exerts Little Influence on Hydrophobic Interactions between Nonpolar Surfaces
Ling, Xiujun,Wilcox, Craig S.
supporting information, p. 14010 - 14014 (2019/11/14)
Polar groups have a solvent ordering effect on water and therefore may affect hydrophobic binding energies for nearby lipophilic surfaces. This would mean that determinations of excess surface free energy association energies require consideration of nearby polar functional groups. This paper reports results of a study to measure this possible effect. It was concluded from the models used here that an anionic polar group nearby a hydrophobic surface has little or no effect on the magnitude of hydrophobic association.
A Practical and Stereoselective In Situ NHC-Cobalt Catalytic System for Hydrogenation of Ketones and Aldehydes
Zhong, Rui,Wei, Zeyuan,Zhang, Wei,Liu, Shun,Liu, Qiang
, p. 1552 - 1566 (2019/06/14)
Homogeneous catalytic hydrogenation of carbonyl groups is a synthetically useful and widely applied organic transformation. Sustainable chemistry goals require replacing conventional noble transition metal catalysts for hydrogenation by earth-abundant base metals. Herein, we report how a practical in situ catalytic system generated by easily available pincer NHC precursors, CoCl2, and a base enabled efficient and high-yielding hydrogenation of a broad range of ketones and aldehydes (over 50 examples and a maximum turnover number [TON] of 2,610). This is the first example of NHC-Co-catalyzed hydrogenation of C=O bonds using flexible pincer NHC ligands consisting of a N-H substructure. Diastereodivergent hydrogenation of substituted cyclohexanone derivatives was also realized by fine-tuning of the steric bulk of pincer NHC ligands. Additionally, a bis(NHCs)-Co complex was successfully isolated and fully characterized, and it exhibits excellent catalytic activity that equals that of the in-situ-formed catalytic system. Catalytic hydrogenation is a powerful tool for the reduction of organic compounds in both fine and bulk chemical industries. To improve sustainability, more ecofriendly, inexpensive, and earth-abundant base metals should be employed to replace the precious metals that currently dominate the development of hydrogenation catalysts. However, the majority of the base-metal catalysts that have been reported involve expensive, complex, and often air- and moisture-sensitive phosphine ligands, impeding their widespread application. From a mixture of the stable CoCl2, imidazole salts, and a base, our newly developed catalytic system that formed easily in situ enables efficient and stereoselective hydrogenation of C=O bonds. We anticipate that this easily accessible catalytic system will create opportunities for the design of practical base-metal hydrogenation catalysts. A practical in situ catalytic system generated by a mixture of easily available pincer NHC precursors, CoCl2, and a base enabled highly efficient hydrogenation of a broad range of ketones and aldehydes (over 50 examples and up to a turnover number [TON] of 2,610). Diastereodivergent hydrogenation of substituted cyclohexanone derivatives was also realized in high selectivities. Moreover, the preparation of a well-defined bis(NHCs)-Co complex via this pincer NHC ligand consisting of a N-H substructure was successful, and it exhibits equally excellent catalytic activity for the hydrogenation of C=O bonds.
DOPAMINE D3 RECEPTOR ANTAGONISTS HAVING A BICYCLO MOIETY
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Paragraph 1087; 1088, (2017/02/28)
The disclosure provides compounds having formula (I), wherein the substituents are as defined herein. The compounds are useful for modulating the dopamine D3 receptor and for treating conditions associated therewith, such as addictions, drug dependency, and psychiatric conditions.
Preparing method for trans- 4- hydroxycyclohexanecarboxylic acid
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Paragraph 0008-0010, (2017/08/27)
The invention discloses a preparing method for trans- 4- hydroxycyclohexanecarboxylic acid. The method comprises the steps of adding p-hydroxybenzoic acid, catalyst and solvent into the high pressure reactor to obtain cis- and trans- 4-hydroxycyclohexanecarboxylic acid, then adding the 4-hydroxycyclohexanecarboxylic acid into the solvent and adding a certain volume of sodium alkoxide as the catalyst, increasing the temperature and obtain trans- 4- hydroxycyclohexanecarboxylic acid with content of over 90% through isomerization reaction. Then obtaining pure trans- 4- isomerization reaction by recrystallization of petroleum ether ethyl acetate. Benefit of the invention: the invention provides a preparing method for trans- 4- hydroxycyclohexanecarboxylic acid. The raw material is easy to obtain and the product can be produced in large scale, which greatly reduces the cost.
A method for synthesizing metabolite pqt (by machine translation)
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Paragraph 0029; 0031, (2017/01/02)
The invention relates to two kinds of pqt of the synthetic method of metabolic product, belongs to the technical field of medicament, are respectively to pqt and 4 the hydroxy [...] cyclohexane carboxylic acid methyl ester as the raw material, pqt and cyclohexenols -3 the [...] formic acid as the raw material to synthesize the pqt two metabolic product. The advantages of: the invention the first time the two portions metabolic product. And, these two kinds of pqt metabolic product of simple synthesis technology, high purity of the product. (by machine translation)
Tetraoxanes as inhibitors of apicomplexan parasites Plasmodium falciparum and Toxoplasma gondii growth and anti-cancer molecules
Opsenica, Dejan M.,Radivojevic, Jelena,Matic, Ivana Z.,?tajner, Tijana,Kne?evic-U?aj, Slavica,Djurkovic-Djakovic, Olgica,?olaja, Bogdan A.
, p. 1339 - 1359 (2016/02/18)
New cyclohexylidene 1,2,4,5-tetraoxanes with polar guanidine and urea based groups were synthesized and evaluated for their antimalarial activity against chloroquine resistant and susceptible Plasmodium falciparum strains. The derivatives showed moderate, nM range antimalarial activities and low cytotoxicity. The N-phenylurea derivative 24 exhibited the best resistance indices (RIW2 = 0.44, RITM91C235 = 0.80) and was not toxic against human normal peripheral blood mononuclear cells (IC50 > 200 μM). Seven derivatives were tested in vitro against four human cancer cell lines and they demonstrated high selectivity toward leukaemia K562 cells. One compound, derivative 21 with a primary amino group, was the first tetraoxane tested in vivo against Toxoplasma gondii as another apicomplexan parasite. Subcutaneous administration at a dose of 10 mg kg-1 day-1 for 8 days allowed the survival of 20 % of infected mice, thus demonstrating the high potential of tetraoxanes for the treatment of apicomplexan parasites.
A Developability-Focused Optimization Approach Allows Identification of in Vivo Fast-Acting Antimalarials: N -[3-[(Benzimidazol-2-yl)amino]propyl]amides
Keurulainen, Leena,Vahermo, Mikko,Puente-Felipe, Margarita,Sandoval-Izquierdo, Elena,Crespo-Fernández, Benigno,Guijarro-López, Laura,Huertas-Valentín, Leticia,De Las Heras-Due?a, Laura,Leino, Teppo O.,Siiskonen, Antti,Ballell-Pages, Lluís,Sanz, Laura M.,Casta?eda-Casado, Pablo,Jiménez-Díaz, M. Belén,Martínez-Martínez, María S.,Viera, Sara,Kiuru, Paula,Calderón, Félix,Yli-Kauhaluoma, Jari
supporting information, p. 4573 - 4580 (2015/06/25)
Malaria continues to be a major global health problem, being particularly devastating in the African population under the age of five. Artemisinin-based combination therapies (ACTs) are the first-line treatment recommended by the WHO to treat Plasmodium falciparum malaria, but clinical resistance against them has already been reported. As a consequence, novel chemotypes are urgently needed. Herein we report a novel, in vivo active, fast-acting antimalarial chemotype based on a benzimidazole core. This discovery is the result of a medicinal chemistry plan focused on improving the developability profile of an antichlamydial chemical class previously reported by our group. (Graph Presented).
Degradation of a model naphthenic acid, cyclohexanoic acid, by vacuum UV (172 nm) and UV (254 nm)/H2O2
Drzewicz, Przemyslaw,Afzal, Atefeh,El-Din, Mohamed Gamal,Martin, Jonathan W.
experimental part, p. 12067 - 12074 (2011/02/27)
The mechanism of hydroxyl radical initiated degradation of a typical oil sands process water (OSPW) alicyclic carboxylic acid was studied using cyclohexanoic acid (CHA) as a model compound. By use of vacuum ultraviolet irradiation (VUV, 172 nm) and ultraviolet irradiation in the presence of hydrogen peroxide UV(254 nm)/H2O2, it was established that CHA undergoes degradation through a peroxyl radical. In both processes the decay of the peroxyl radical leads predominantly to the formation of 4-oxo-CHA, and minor amounts of hydroxy-CHA (detected only in UV/H2O 2). In UV/H2O2, additional 4-oxo-CHA may also have been formed by direct reaction of the oxyl radical with H-O 2. The oxyl radical can be formed during decay of the peroxyl-CHA radical or reaction of hydroxy-CHA with hydroxyl radical. Oxo- and hydroxy-CHA further degraded to various dihydroxy-CHAs. Scission of the cyclohexane ring was also observed, on the basis of the observation of acyclic byproducts including heptadioic acid and various short-chain carboxylic acids. Overall, the hydroxyl radical induced degradation of CHA proceeded through several steps, involving more than one hydroxyl radical reaction, thus efficiency of the UV/H 2O2 reaction will depend on the rate of generation of hydroxyl radical throughout the process. In real applications to OSPW, concentrations of H2O2 will need to be carefully optimized and the environmental fate and effects of the various degradation products of naphthenic acids considered.
Development of fluorine-18-labeled 5-HT(1A) antagonists
Lang, Lixin,Jagoda, Elaine,Schmall, Bernard,Vuong, Bik-Kee,Adams, H. Richard,Nelson, David L.,Carson, Richard E.,Eckelman, William C.
, p. 1576 - 1586 (2007/10/03)
We have synthesized five fluorinated derivatives of WAY 100635, N-{2- [4-(2-methoxyphenyl)piperazino]ethyl)-N-(2-pyridyl)cyclohexanecarboxamide (4a), using various acids in place of the cyclohexanecarboxylic acid (CHCA, 2a) in the reaction scheme. The five acids are 4-fluorobenzoic acid (FB, 2b), 4-fluoro-3-methylbenzoic acid (MeFB, 2c), trans-4- fluorocyclohexanecarboxylic acid (FC, 2d), 4-(fluoromethyl)benzoic acid (FMeB, 2e), and 3-nitro-4(fluoromethyl)benzoic acid (NFMeB, 2f) (see Scheme 1). These compounds were radiolabeled with fluorine-18, and their biological properties were evaluated in rats and compared with those of [11C]carbonyl WAY 100635 ([carbonyl-11C]4a). [Carbonyl-11C]4a cleared the brain with a biological half-life averaging 41 min. The metabolite-corrected blood radioactivity had a half-life of 29 min. [18F]FCWAY ([18F]4d) gave half- lives and intercepts comparable to [carbonyl11C]4a in the brain, but the blood clearance was faster. [18F]FBWAY ([18F]4b) showed an early rapid net efflux from the whole brain, clearing with a biological half-life of 35 min. The metabolite-corrected blood half-life was 41 min. The comparable whole brain and blood half-lives for Me[18F]FBWAY ([18F]4c) were 16 and 18 min, respectively. For each compound, the corresponding carboxylic acid was identified as a major metabolite in blood. Fluoride was also found after injection of [18F]4d. However, for all compounds there was a good correlation (R > 0.97) between the differential uptake ratio (DUR, (%ID/g) x body weight (g)/100) in individual rat brain regions at 30 min after injection and the concentration of receptors as determined by in vitro quantitative autoradiography in rat. Specific binding ratios [region of interest (ROI)/cerebellum-1] in control studies for cortex (Ctx) and hippocampus (H) were higher for [carbonyl11C]4a and [18F]4d compared to [18F]4b and [18F]4c. [18F]4d has similar pharmacokinetic properties and comparable specific binding ratios to [carbonyl-11C]4a. Fifty nanomoles of 4a blocked only 30% of the specific binding of [18F]4d, while complete blockade was obtained from co-injection of 200 nmol of 4a (H/Cb-1 from 17.2 to 0.6). [18F]4b and [18F]4c showed lower specific binding ratios than [carbonyl-11C]4a and [18F]4d. [18F]4c was superior to [18F]4b since its specific binding was more readily blocked by 4a. These studies suggest that [18F]4c should be a useful compound to assess dynamic changes in serotonin levels while [18F]4d, with its high contrast and F-18 label, should provide better statistics and quantification for static measurement of 5-HT(1A) receptor distribution.
