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11.
A sulfonic acid functionalized ionic liquid was designed, synthesized and successfully used as a Brønsted acid catalyst for the one-pot synthesis of α-aminophosphonates containing benzothiazole at room temperature under solvent-free conditions in excellent yields. The advantages of this method are the reusability of the catalyst, high conversion, short reaction time, and simple experimental procedure. A computer modeling and docking simulation of ligand bond complexes of cyclin-dependent kinase 2 are presented. The results indicate that diethyl ((4-(dimethylamino) phenyl) ((6-nitrobenzo[d]thiazol-2-yl) amino)methyl)phosphonate was found to be the best selective inhibitor of cyclin-dependent kinase 2.  相似文献   
12.
A code is n-deletion correcting if it is possible to correct any n deletion of symbols having occurred in transmission of codewords. In this paper, we present explicit constructions of n-deletion correcting codes for arbitrary values of n using generalized Reed–Solomon codes and their subcodes.   相似文献   
13.
A novel hybrid material, (CeIII‐MoVI)Ox/aniline, with rod‐like morphology is synthesized through a wet chemical method using Mo3O10(C6H5NH3)2.2H2O nanowires as precursor. The synthesized materials are characterized by XRD, XPS, SEM, TEM, FTIR, Raman, UV–Vis, TGA, and elemental analysis. Also, their catalytic activities as a hybrid catalyst are tested in the selective oxidation of sulfides using hydrogen peroxide as a green oxidant. The proposed novel hybrid catalyst shows an excellent performance under green conditions at mild temperature. Furthermore, the scalability of the oxidation reaction is shown by making multi‐gram quantities at optimized conditions.  相似文献   
14.
This work describes optimization of headspace single drop micro-extraction for extraction of five organophosphorus pesticides; thionazin, sulfotep, dimethoate, disulfoton and parathion in soil. Ultrasound has also been used successfully to improve and accelerate the extraction of the analytes from the sample. The optimized extraction performance was obtained when the experimental parameters were set as follows; 3.0 μL of octanol as extraction solvent, high ionic strength (20% sodium chloride), 1:1 (w/v) sample dilution with water, extraction temperature at 60 °C for 30 min; applying ultrasound and without any pH adjustment. The optimized method was linear over the calibration range (5–200 and 10–300 for different analytes) with limits of detection of 0.1–2.0 ng g−1. The enrichment factor for OPPs was 1.4–12.7 and the method was also reproducible with the relative standard deviations (RSD%) of 2.1–6.9%.  相似文献   
15.

An eco-friendly method for diversity-oriented synthesis of substituted dihydropyrano[2,3-c]pyrazole and benzylpyrazolyl coumarin derivatives has been achieved via one-pot and multicomponent reaction in the presence of PdO/Al-SBA-15 as an efficient and recyclable catalyst in H2O/EtOH under reflux conditions. The significant merits of this method are wide scope, high yields of the desired products, short reaction times and simple workup procedure. In addition, this nanocatalyst was simply recovered and reused five times without significant loss in catalytic activity and also performance.

Graphical abstract
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16.

Abstract  

Protonation of the highly reactive 1:1 intermediate produced in the reaction between alkyl or aryl isocyanides and electron-deficient acetylenic esters with 3-hydroxy-1H-phenalene-1-one leads to a vinylisonitrilium cation, which undergoes an addition reaction with the conjugate base of the 3-hydroxy-1H-phenalene-1-one to produce biologically interesting dialkyl 10-(alkyl or arylamino)-7-oxo-7H,8H-naphtho[1,8-gh]chromene-8,9-dicarboxylates in moderate to fairly good yields at room temperature.  相似文献   
17.
3-Acyl-coumarins were obtained in high yields from ortho-hydroxybenzaldehydes and ethyl acetoacetate or ethyl benzoylacetate in acetonitrile in the presence of a catalytic amount of mesoporous molecular sieve MCM-41. 3-Acyl-coumarins were obtained in high yields from ortho-hydroxybenzaldehydes and ethyl acetoacetate or ethyl benzoylacetate in acetonitrile in the presence of a catalytic amount of mesoporous molecular sieve MCM-41.  相似文献   
18.
Aromatic aldehydes were reacted in a one-pot reaction with enolizable ketones, acetonitrile, and acetyl chloride in the presence of Mn(bpdo)2Cl2/MCM-41 under reflux condition or at 80 °C to afford the corresponding β-acetamido ketones in good yields.  相似文献   
19.
Palladium nanoparticles were first synthesized through the thermal decomposition method and subsequently immobilized on ordered mesoporous silica material, SBA‐15, to afford PdO/SBA‐15 catalyst. The synthesized catalyst was characterized by X‐ray diffraction, nitrogen adsorption‐desorption measurement, transmission electron microscopy, and inductively coupled plasma atomic emission spectrometry. The catalytic activity was tested for the aerobic oxidation of alcohols. Easy recovery, high yeilds and relatively short reaction times were observed for the mentioned catalyst.  相似文献   
20.
Benzoxazoles can be rapidly and efficiently synthesized from acyl chloride with 2-aminophenols in one simple step, which provided a practical and efficient method for high-throughput synthesis of this important class of heterocyclic compounds.  相似文献   
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