168 research outputs found
Suzuki-Miyaura coupling under microwave enhanced conditions: Synthesis of 2-(hetero)aryl benzimidazoles
An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based core under microwave-assisted conditions has been developed and is described. This protocol, which incorporates appendage diversity on this potential scaffold, is found to be compatible with a wide range of electronicallyand sterically-divergent (hetero)aryl boronic acids. The use of the PdCl2/(SPhos) catalytic system allows the formation of a stable and highly active LPd(0) species which was found to be critical for the successful synthesis of these novel, pharmacologically-relevant molecules. © AUTHOR(S).Russian Foundation for Basic Research, RFBR: 170300641AThe authors are thankful to SAIF, Indian Institute of Technology, Madras, for providing all the analytical data and spectra. Vasiliy A. Bakulev is thankful to Russian Foundation for Basic Research (Grant # 170300641A)
Synthesis, Crystal structure, DFT calculations and antimicrobial activity of 4-(4-fluoro-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid diethyl ester
The title compound was synthesized and confirmed by FT-IR, 1H, 13C NMR analysis. The molecular structure of the compound was precisely determined by Single Crystal X-ray Diffraction (SC-XRD) analysis. The crystalized compound shows P21/C & monoclinic crystal system with cell parameters a = 9.7768 (5), b = 7.4005(3) and c = 24.8099 (12), β=93.734(2)°.The structural and electronic properties of the compound were carried out by Density Functional Theory (DFT) calculations. The compound exhibited H-bonding between N1-H1A-O1 with bond distance 2.98(7) A°).The energy gap Egap 4.53eV and Egap= 4.34eV for crystal and DFT method respectively. The molecular orbitals energies were studied through Highest Unoccupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis. The softness and hardness of the molecule was studied through Global Chemical Reactivity Descriptors (GCRD). The electrophilic and nucleophilic characters were studied through Molecular Electrostatic Potential (MEP) studies. The antimicrobial studies were carried out by in-vitro method against 6 microorganisms
PALLADIUM CATALYZED SYNTHESIS OF NOVEL TACRINE DERIVATIVES
This work was supported by Ministry of Science and Higher Education of the Russian Federation, grant # 075-15-2020-777 and the Russian Science Foundation, grants ### 22-23-20189, 21-13-00304 and 20-73-10205
Synthesis, Characterization, Crystal Structure of 4-(4-Bromo-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic Acid Diethyl Ester: Hirshfeld Surface Analysis and DFT Calculations
The title compound dihydro-pyridine was synthesized and structure is established by FT-IR, 1H NMR, and 13C NMR spectral analysis. The SC-XRD analysis has been carried out for the determination of molecular structure and its disclosed that crystal relates to monoclinic crystal phase, P21/n1 space group and cell parameters are a= 10.2314(2), b = 7.5215(1), c = 24.5475(4), α = 90, β = 97.921(1)° γ = 90 with 0.34 x 0.33 x 0.30 crystal size. The crystal lattice exhibits inter-molecular H-bonding between N1—H1A—O1. Further inter contacts of the crystal lattice were determined by 3-D Hirshfeld surface (HSA) as well as percentage of contributions have been computed through 2D finger plot depiction. Moreover, bond length, bond angle and torsion angles have been correlated to respective output results of B3LYP/6-311++G(d,p). The electrophilic and nucleophilic characters have been studied through molecular electrostatic potential (MEP) analysis. © 2020 NIODC. All rights reserved ©2022 National Information and Documentation Center (NIDOC).We record our sincere thanks to the (CIMF), Periyar University, Salem for providing the facilities for single crystal XRD analysis and SAIF-VIT for providing 1H, 13C NMR analysis. The authors also thanks to Jamal instrumentation facility (JIF), Post Graduate and Research Department of Chemistry, Jamal Mohamed College, Tiruchirappalli for providing necessary lab facilities
Transient parkinsonism in isolated extrapontine myelinolysis
Extrapontine myelinolysis (EPM) is a rare cause of parkinsonism. In this case report, we describe a 63-year-old woman with parkinsonism due to EPM after correction of hyponatremia. During a 4-year follow-up, both the clinical features of parkinsonism and the changes on magnetic resonance imaging resolved. Parkinsonism due to EPM should be recognized as it has a good prognosis
Extrapontine myelinolysis presenting as acute parkinsonism
BACKGROUND: Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity. CASE PRESENTATION: A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone. CONCLUSION: Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans
A novel Bezier curve control point search algorithm for autonomous navigation using N-order polynomial search with boundary conditions
The study on path planning at intersections such as roundabouts has become a crucial aspect for autonomous vehicle development. This is due to the nature of the intersections, which can vary depending on the level of complexity. Path generation for an autonomous vehicle in a roundabout cornering is done using different curve fitting methods such as clothoid curves, Bezier curves, etc. However, the Bezier curve is the most widely used in the curve fitting algorithm for vehicle path planning as it can generate a possible number of path maneuvers. However, the main challenge when using the Bezier curve fitting algorithm is finding its control points. The control points are a crucial part of Bezier curve generation as it determines the curvature and shape of the curve. Therefore, a new technique for finding the control points of a Bezier curve is presented in this paper. The process starts with random points selection along the path. Specific random points will be selected through which the curve should pass through. The algorithm then expands the generalized Bezier curve equations to solve the mathematical problem and eventually, the simultaneous equation will be formed for the control point generation. The generated control points will be able to generate a proper Bezier curve that passes through all the selected points along the path. The generated equations are further validated in a test case study to show the effectiveness of the proposed method. This method is able to generate the desired Bezier curve through the selected points. This will open possibilities to generate a smoother predictive motion output using the Bezier curve fitting technique
Some imidazolyl benzamides as potent antibacterial agents
A series of imidazolyl benzamides containing urea has been efficiently synthesized and evaluated for their antibacterial properties. Some of the molecules exhibited promising antibacterial activity when compared to the reference standard, Ciprofloxacin. © 2020 Author(s)
Discovering New Strong Gravitational Lenses in the DESI Legacy Imaging Surveys
We have conducted a search for new strong gravitational lensing systems in the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys’ Data Release 8. We use deep residual neural networks, building on previous work presented in Huang et al. (2020). These surveys together cover approximately one third of the sky visible from the northern hemisphere, reaching a z-band AB magnitude of ∼ 22.5. We compile a training sample that consists of known lensing systems as well as non-lenses in the Legacy Surveys and the Dark Energy Survey. After applying our trained neural networks to the survey data, we visually inspect and rank images with probabilities above a threshold. Here we present 1210 new strong lens candidates
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