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961.
Research on Chemical Intermediates - In spite of having significant pharmacological importance, scalable synthesis of 2,2,4-trimethyl-1,2-H-dihydroquinoline (TMQ) is always being cumbersome due to... 相似文献
962.
Murugavel Saminathan Saranya Kanagarajan Ravikumar Chandrasekaran Archana Sivasubramaniyan Ranganathan Raja Ponnusamy Alagusundaram 《中国化学会会志》2020,67(6):1100-1112
Two novel compounds 1-(5-[4-fluorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (FSCN) and 1-(5-[4-chlorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (ClSCN) were synthesized and characterized by SC-XRD, 1H NMR, 13C NMR, FTIR, and UV methods. The X-ray diffraction studies were utilized to prove the 3D crystal structures of FSCN and ClSCN. In both the compounds, the packing is mostly driven by C H⋯N, C H⋯O, and C H⋯π (benzene ring as an acceptor) interactions. In ClSCN, additionally, the π⋯π interaction is observed between the pyrazole ring of one molecule and the benzene ring of the other molecule. The experimental values were compared with the results of DFT/B3LYP/6-311G++(d,p) theoretical computations. The pharmacological screening for FSCN and ClSCN was performed using molinspiration and PreADMET web server. To analyze antibacterial inhibition of the synthesized ligands and Ciprofloxacin (control drug) were interacted with antibacterial protein Thymidylate Kinase (TMK) (PDB ID: 4QGG) with the help of AutoDock Vina tool. The ADMET and docking results of FSCN and ClSCN pointed out the better drug likeness nature and good inhibition behavior with TMK protein. The antibacterial in vitro studies suggested that FSCN compound inhibited well with antibacterial strains than that of ClSCN. The current investigation suggests that with further improvements, our compounds could be preferred as substitute medicine for bacterial diseases. 相似文献
963.
L-proline/urea catalyzed,novel, and eco-friendly synthesis of coumarin substituted-3-indoloxanthenes
Hari Krishna Reddy Vallam Reddy Venkateswara Rao Anna 《Journal of heterocyclic chemistry》2020,57(11):3980-3987
A green and eco-friendly synthesis of coumarin substituted-3-indoloxanthenes 4(a-l) has been developed using urea/L-proline as simple catalyst. Two efficient methods have been described for the synthesis of these 3-indoloxanthene derivatives. In the first method, Knoevenagel condensation, then Pinner cyclisation followed by 1,4 addition between 4-hydroxy-1-methyl-2-oxo-1,2-dihydrocoumarin-3-carbaldehyde 1(a-b) , with cyclohexane-1,3-dione (2) and indole 3(a-f) using of L-proline as catalyst was described. In the second method, urea/thiourea catalyzes the same reaction at 100°C for 10 minutes to afford the title compounds 4(a-l) . These two protocols involve eco-friendly and inexpensive catalysts, give excellent yields of the clean products without the need of column chromatography for their isolation or purification. 相似文献
964.
Dr. Stephanie Chapman Dr. Marina Carravetta Dr. Ivana Miletto Dr. Cara M. Doherty Hannah Dixon Dr. James D. Taylor Prof. Enrica Gianotti Prof. Jihong Yu Prof. Robert Raja 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(44):19729-19737
Porosity and acidity are influential properties in the rational design of solid-acid catalysts. Probing the physicochemical characteristics of an acidic zeotype framework at the molecular level can provide valuable insights in understanding intrinsic reaction pathways, for affording structure–activity relationships. Herein, we employ a variety of probe-based techniques (including positron annihilation lifetime spectroscopy (PALS), FTIR and solid-state NMR spectroscopy) to demonstrate how a hierarchical design strategy for a faujasitic (FAU) zeotype (synthesized for the first time, via a soft-templating approach, with high phase-purity) can be used to simultaneously modify the porosity and modulate the acidity for an industrially significant catalytic process (Beckmann rearrangement). Detailed characterization of hierarchically porous (HP) SAPO-37 reveals enhanced mass-transport characteristics and moderated acidity, which leads to superior catalytic performance and increased resistance to deactivation by coking, compared to its microporous counterpart, further vindicating the interplay between porosity and moderated acidity. 相似文献
965.
In this paper, the authors study the asymptotic behavior of solutions of second-order neutral type difference equations of the form
Δ2(yn+pyn−k)+f(n,yn−ℓ)=0,n