scholarly journals 2-(2-(4-Methoxyphenyl)-4,9-dimethyl-7-oxo-7H-furo[2,3-f]chromen-3-yl)acetic Acid

Molbank ◽  
10.3390/m1304 ◽  
2021 ◽  
Vol 2021 (4) ◽  
pp. M1304
Author(s):  
Boris V. Lichitsky ◽  
Andrey N. Komogortsev ◽  
Valeriya G. Melekhina
Keyword(s):  
Acetic Acid ◽  
High Resolution Mass Spectrometry ◽  
13C Nmr Spectroscopy ◽  
Acid Moiety ◽  
Acidic Media ◽  
New Approach ◽  
Multicomponent Condensation ◽  
Reaction Proceeds ◽  
Initial Interaction ◽  
First Time

For the first time, we describe a new approach towards the synthesis of previously unknown 2-(2-(4-methoxyphenyl)-4,9-dimethyl-7-oxo-7H-furo[2,3-f]chromen-3-yl)acetic acid. The presented method is based on the multicomponent condensation of 5-hydroxy-4,7-dimethyl-2H-chromen-2-one, 4-methoxyphenylglyoxal and Meldrum’s acid. It was shown that the studied reaction proceeds in two steps including the initial interaction of starting materials in MeCN and the final formation of furylacetic acid moiety in acidic media. The structures of the obtained compound were established by 1H, 13C-NMR spectroscopy and high-resolution mass spectrometry.

scholarly journals 2-(2-(4-Methoxyphenyl)furo[3,2-h]quinolin-3-yl)acetic Acid

Molbank ◽  
10.3390/m1315 ◽  
2022 ◽  
Vol 2022 (1) ◽  
pp. M1315
Author(s):  
Boris V. Lichitsky ◽  
Andrey N. Komogortsev ◽  
Valeriya G. Melekhina
Keyword(s):  
Mass Spectrometry ◽  
Acetic Acid ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
2D Nmr ◽  
Target Product ◽  
Atom Economy ◽  
Initial Interaction ◽  
Work Up ◽  
Resolution Mass

A simple and efficient protocol for the synthesis of the previously unknown 2-(2-(4-methoxyphenyl)furo[3,2-h]quinolin-3-yl)acetic acid was elaborated. The suggested method is based on the telescoped multicomponent reaction of 8-hydroxyquinoline, 4-methylglyoxal, and Meldrum’s acid. The studied process includes the initial interaction of the starting compounds in MeCN followed by intramolecular cyclization to the target product in refluxing acetic acid. The advantage of this approach is the application of readily available starting materials, atom economy, and a simple work-up procedure. The structure of the synthesized furylacetic acid derivative was proven by 1H, 13C, 2D-NMR, IR spectroscopy, and high-resolution mass spectrometry.

An Unprecedented Cyano-Induced Sodium Nitrite-Catalyzed C(sp3)-H and C(sp2)-H Coupling Reaction

2018 ◽  
Vol 15 (7) ◽  
pp. 989-994 ◽  
Author(s):  
Ling Li ◽  
Bo Su ◽  
Yuxiu Liu ◽  
Qingmin Wang
Keyword(s):  
Sodium Nitrite ◽  
Oxidative Coupling ◽  
High Resolution Mass Spectrometry ◽  
Coupling Reaction ◽  
13C Nmr Spectroscopy ◽  
Coupling Reactions ◽  
Reaction Conditions ◽  
1H And 13C Nmr ◽  
Oxidative Coupling Reaction ◽  
Oxidative Coupling Reactions

Aim and Objective: During the investigation of sodium nitrite-catalyzed oxidative coupling reaction of aryls, an unprecedented C(sp2)-H and C(sp3)-H coupling of substituted 2-aryl acetonitrile was found. Materials and Methods: The structure of the coupled product was confirmed by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS), and comparison of its derivatives with known compounds. The effects of methoxy group in the benzene ring on the reaction were evaluated. Results: The optimized reaction conditions are summarized as follows: CF3SO3H/substrate = 1.5 equiv., NaNO2/substrate = 0.3 equiv., CH3CN as solvent. 2-(4-Methoxyphenyl)acetonitrile and 2-(3,4,5- trimethoxyphenyl)acetonitrile could also generate C(sp2)-H and C(sp3)-H coupling. The coupling reaction occurred as a typical radial mechanism. Conclusion: An unprecedented cyano-induced, NaNO2-catalyzed oxidative C(sp3)-H and C(sp2)-H coupling was reported. The reaction proceeded under very mild conditions, using O2 in the air as terminal oxidant. The unique oxidative manner might provide more inspiration for the development of intriguing oxidative coupling reactions.

scholarly journals Analysis of Pembrolizumab in Human Plasma by LC-MS/HRMS. Method Validation and Comparison with Elisa

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 621
Author(s):  
Aurélien Millet ◽  
Nihel Khoudour ◽  
Jérôme Guitton ◽  
Dorothée Lebert ◽  
François Goldwasser ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Human Plasma ◽  
High Resolution Mass Spectrometry ◽  
Internal Standard ◽  
Therapeutic Drug ◽  
Limit Of Quantification ◽  
Immunoglobulin G4 ◽  
Positive Mode ◽  
Surrogate Peptide ◽  
First Time

Pembrolizumab is a humanized immunoglobulin G4-kappa anti-PD1 antibody used in the treatment of different solid tumors or haematological malignancies. A liquid chromatography coupled with a high resolution mass spectrometry (orbitrap technology) method was fully developed, optimized, and validated for quantitative analysis of pembrolizumab in human plasma. A mass spectrometry assay was used for the first time a full-length stable isotope-labelled pembrolizumab-like (Arginine 13C6-15N4 and Lysine 13C6-15N2) as an internal standard; the sample preparation was based on albumin depletion and trypsin digestion and, finally, one surrogate peptide was quantified in positive mode. The assay showed good linearity over the range of 1–100 μg/mL, a limit of quantification at 1 μg/mL, excellent accuracy from 4.4% to 5.1%, and also a between-day precision below 20% at the limit of quantification. In parallel, an in-house ELISA was developed with a linearity range from 2.5 to 50 µg/mL. Then, results were obtained from 70 plasma samples of cancer patients that were treated with pembrolizumab and quantified with both methods were compared using the Passing-Bablok regression analysis and Bland-Altman plotting. The LC-MS/HRMS method is easy to implement in the laboratory for use in the context of PK/PD studies, clinical trials, or therapeutic drug monitoring.

A multi-manned assembly line balancing problem with classified teams: a new approach

2016 ◽  
Vol 36 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Hamid Yilmaz ◽  
Mustafa Yilmaz
Keyword(s):  
Design Methodology ◽  
Assembly Line ◽  
Assembly Line Balancing ◽  
Line Balancing ◽  
Test Problems ◽  
New Approach ◽  
Content Type ◽  
Line Test ◽  
Assembly Line Balancing Problem ◽  
First Time

Purpose – Within team-oriented approaches, tasks are assigned to teams before being assigned to workstations as a reality of industry. So it becomes clear, which workers assemble which tasks. Design/methodology/approach – Team numbers of the assembly line can increase with the number of tasks, but at the same time, due to physical situations of the stations, there will be limitations of maximum working team numbers in a station. For this purpose, heuristic assembly line balancing (ALB) procedure is used and mathematical model is developed for the problem. Findings – Well-known assembly line test problems widely used in the literature are solved to indicate the effectiveness and applicability of the proposed approach in practice. Originality/value – This paper draws attention to ALB problem in which workers have been assigned to teams in advance due to the need for specialized skills or equipment on the line for the first time.

Synthesis and characterization of meso-to-meso directly linked porphyrin-diazaporphyrin triads

2018 ◽  
Vol 22 (09n10) ◽  
pp. 814-820
Author(s):  
Yingying Jia ◽  
Ling Xu ◽  
Bangshao Yin ◽  
Mingbo Zhou ◽  
Jianxin Song
Keyword(s):  
Nickel Complex ◽  
High Resolution Mass Spectrometry ◽  
Dihedral Angles ◽  
X Ray Diffraction ◽  
Extinction Coefficients ◽  
X Ray ◽  
H Nmr ◽  
First Time ◽  
Molar Extinction Coefficients

Beginning with 5,10,15-triarylporphyrin-nickel complex, five meso-to-meso directly linked porphyrin-diazaporphyrin triads were successfully prepared for the first time through a series of reactions including formylation via Vilsmeier–Haack reaction, condensation with pyrrole, bromination with [Formula: see text]-Bromosuccinimide (NBS), oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), metal-templated cyclization of dibromodipyrrin-metal complexes with NaN[Formula: see text] and demetalization. All these triads were comprehensively characterized by [Formula: see text]H NMR, high-resolution mass spectrometry and UV-vis absorption. In addition, the structure of compound 6Ni was unambiguously determined by X-ray diffraction analysis, which showed that the two dihedral angles are both 86.65 (4)[Formula: see text] between each mean plane of porphyrin and that of central diazaporphyrin The UV-vis absorption spectra disclosed that the longest wavelengths of Soret bands and Q bands for these triads were observed at 429 and 642 nm, respectively. In contrast to diazaporphyrin-porphyrin dyads, diazaporphyrin dimers and diazaporphyrin monomers reported previously the molar extinction coefficients, particularly for triad 8Ni are much higher.

A New Approach for the Fabrication of Tetragonal BaTiO3 Nanoparticles

2021 ◽  
Vol 21 (4) ◽  
pp. 2692-2701
Author(s):  
Vu T. Tan ◽  
La The Vinh ◽  
Vu Minh Khoi ◽  
Huynh Dang Chinh ◽  
Pham Van Tuan ◽  
...  
Keyword(s):  
Ferroelectric Properties ◽  
Particle Size Effect ◽  
Ferroelectric Material ◽  
Tem Analysis ◽  
New Approach ◽  
Xrd Pattern ◽  
Munk Function ◽  
Oxide Nanoparticle ◽  
First Time ◽  
Batio3 Nanoparticles

For the first time, the BaTiO3 nano-sized particles were obtained through solid-state reaction by employing the titanium oxide nanoparticle. Meanwhile, by using TiO2 with micro-sized particles, the synthesized BaTiO3 shows the micro-sized. The XRD pattern confirms that both BaTiO3 nano-sized and micro-sized particles display the tetragonal structure. Both SEM and TEM analysis revealed that the size of the nano-sized material is in the range of 30–50 nm; in the meantime, the microsized material shows a size of 500 nm. The Eg of both BaTiO3 micro-sized and nano-sized were calculated by using the Kubelka-Munk function. The shifted bandgap of BaTiO3 nano-sized particle is nearly 0.24 eV larger than that of BaTiO3 miro-sized particle due to the particle size effect. The P-E measurement of n-BaTiO3 proved that the obtained BaTiO3 nano-sized is ferroelectric material. The result may provide a new route for the fabrication of barium titanate nanoparticle with ferroelectric properties.

scholarly journals Exploiting superspace to clarify vacancy and Al/Si ordering in mullite

IUCrJ ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 497-509 ◽  
Author(s):  
Paul Benjamin Klar ◽  
Iñigo Etxebarria ◽  
Gotzon Madariaga
Keyword(s):  
Density Functional ◽  
X Ray Diffraction ◽  
Intrinsic Structure ◽  
Functional Theory ◽  
New Approach ◽  
X Ray ◽  
Vacancy Ordering ◽  
Harmonic Modulation ◽  
First Time

Synchrotron single-crystal X-ray diffraction has revealed diffuse scattering alongside sharp satellite reflections for different samples of mullite (Al4+2xSi2−2xO10−x). Structural models have been developed in (3+1)-dimensional superspace that account for vacancy ordering and Al/Si ordering based on harmonic modulation functions. A constraint scheme is presented which explains the crystal-chemical relationships between the split sites of the average structure. The modulation amplitudes of the refinements differ significantly by a factor of ∼3, which is explained in terms of different degrees of ordering,i.e.vacancies follow the same ordering principle in all samples but to different extents. A new approach is applied for the first time to determine Al/Si ordering by combining density functional theory with the modulated volumes of the tetrahedra. The presence of Si–Si diclusters indicates that the mineral classification of mullite needs to be reviewed. A description of the crystal structure of mullite must consider both the chemical composition and the degree of ordering. This is of particular importance for applications such as advanced ceramics, because the physical properties depend on the intrinsic structure of mullite.

scholarly journals NEW PHARMACOLOGICALLY ACTIVE COMPOUNDS BASED ON 5-HYDROXY-7-METHOXY-2-PHENYLCHROMAN-4-ONE

2021 ◽  
Vol 3 ◽  
pp. 119-127
Author(s):  
G.M. Baisarov ◽  
◽  
S.M. Adekenov ◽  
Keyword(s):  
Nmr Spectroscopy ◽  
13C Nmr ◽  
Potassium Carbonate ◽  
13C Nmr Spectroscopy ◽  
1H And 13C Nmr ◽  
Pharmacologically Active ◽  
Pharmacologically Active Compounds ◽  
First Time

The reaction of 5-hydroxy-7-methoxy-2-phenylchroman-4-one with dibromoalkanes in acetone in the presence of potassium carbonate proceeds according to the Michael’s retro-reaction O-alkylation and leads to the formation of the corresponding 2-(bromo-alkoxy) chalcones. The structure of the synthesized compounds was confirmed by IR-, 1H- and 13C-NMR spectroscopy. The cytotoxic, hepatoprotective and anti-inflammatory effects of chalcone derivatives (2-3) were studied for the first time in vitro and in vivo.

scholarly journals Elephant Herding Optimization for Energy-Based Localization

2018 ◽  
Author(s):  
Sérgio Correia ◽  
Marko Beko ◽  
Luís Cruz ◽  
Slavisa Tomic
Keyword(s):  
Source Localization ◽  
Wireless Sensors ◽  
Performance Comparison ◽  
Sensor Nodes ◽  
Convex Relaxations ◽  
Noisy Environments ◽  
New Approach ◽  
Metaheuristic Methods ◽  
Simulation Results ◽  
First Time

This work addresses the energy-based source localization problem in wireless sensors networks. Instead of circumventing the maximum likelihood (ML) problem by applying convex relaxations and approximations (like all existing approaches do), we here tackle it directly by the use of metaheuristics. To the best of our knowledge, this is the first time that metaheuristics is applied to this type of problems. More specifically an elephant herding optimization (EHO) algorithm is applied. Through extensive simulations, the key parameters of the EHO algorithm are optimized such that they match the energy decay model between two sensor nodes. A detailed analysis of the computational complexity is presented, as well as performance comparison between the proposed algorithm and existing non-metaheuristic ones. Simulation results show that the new approach significantly outperforms the existing solutions in noisy environments, encouraging further improvement and testing of metaheuristic methods.

scholarly journals A new solvate of epalerstat, a drug for diabetic neuropathy

2017 ◽  
Vol 73 (8) ◽  
pp. 1264-1267 ◽  
Author(s):  
Okky Dwichandra Putra ◽  
Daiki Umeda ◽  
Kaori Fukuzawa ◽  
Mihoko Gunji ◽  
Etsuo Yonemochi
Keyword(s):  
Hydrogen Bond ◽  
Acetic Acid ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Diabetic Neuropathy ◽  
Dihedral Angle ◽  
Phenyl Ring ◽  
Acid Moiety ◽  
Acta Cryst ◽  
Carboxylic Acid Groups

Epalerstat {systematic name: (5Z)-5-[(2E)-2-methyl-3-phenylprop-2-en-1-ylidene]-4-oxo-2-sulfanylidene-1,3-thiazolidine-3-acetic acid} crystallized as an acetone monosolvate, C15H13NO3S2·C3H6O. In the epalerstat molecule, the methylpropylenediene moiety is inclined to the phenyl ring and the five-membered rhodamine ring by 21.4 (4) and 4.7 (4)°, respectively. In addition, the acetic acid moiety is found to be almost normal to the rhodamine ring, making a dihedral angle of 85.1 (2)°. In the crystal, a pair of O—H...O hydrogen bonds between the carboxylic acid groups of epalerstat molecules form inversion dimers with an R 2 2(8) loop. The dimers are linked by pairs of C—H...O hydrogen bonds, enclosing R 2 2(20) loops, forming chains propagating along the [101] direction. In addition, the acetone molecules are linked to the chain by a C—H...O hydrogen bond. Epalerstat acetone monosolvate was found to be isotypic with epalerstat tertrahydrofuran solvate [Umeda et al. (2017). Acta Cryst. E73, 941–944].

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