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11.
An efficient one‐pot four‐component protocol for the synthesis of imidazo[1,2‐a]pyridines was developed by condensing ethane‐1,2‐diamine ( 2 ), 1,1‐bis(methylthio)‐2‐nitroethene ( 1 ), aldehydes 3 , and activated methylene compounds in EtOH under reflux conditions (Tables 1–3). The features of this procedure are operational simplicity, good yields of products, in situ preparation of heterocyclic ketene aminals (HKA), and catalyst‐free conditions. 相似文献
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A three-component condensation reaction between 2-aminobenzophenone derivatives, formaldehyde or aromatic aldehydes, and ammonium acetate efficiently provides substituted quinazolines in a one-pot reaction in the presence of Brönsted acidic ionic liquid, 1-methylimidazolium triflouroacetate ([Hmim]TFA), in conjunction with aerobic oxidation. The ionic liquid was separated from the reaction mixture by simple extraction and was recycled three times without considerable loss in activity. 相似文献
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Firas Awaja Michael Gilbert Minoo Naebe Georgina Kelly Bronwyn Fox Russell Brynolf Paul J. Pigram 《Polymer Degradation and Stability》2013
Thermoplastic polyolefin panels were treated with a flame, flame & water, and accelerated thermo molecular adhesion process (ATmaP) treatment. XPS, contact angle and adhesion test (pull off) results were acquired over a one year period to determine the changes in the elemental composition, surface energy and adhesion strength respectively over time. All surface-treated thermoplastic polyolefin samples showed a sharp decline in adhesion strength up to an ageing period totalling 6 months. The decline in adhesion strength was correlated with a decline in the nitrogen-containing constituents and C–O functional groups at the surface and a decline in surface energy for the flame & water-treated sample. There was no significant change in adhesion strength for all samples for ageing periods greater than 6 months. ATmaP-treated thermoplastic polyolefin outperformed the other two surface treatments in adhesion strength tests due to ATmaP retaining nitrogen-based functional groups (mainly nitrogen oxides) over the year long study. This retention of functionality allowed for a slower ageing process for ATmaP-treated surfaces in comparison to the other surface treatments. 相似文献
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New and efficient multi-component methods have been developed for the synthesis of spirooxindoles in the presence of a catalytic amount of p-TSA as an inexpensive and available catalyst in EtOH under ultrasound irradiation. The method is simple, starts from readily accessible commercial starting materials, and provides biologically interesting products in good yields and short reaction times. 相似文献
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The combination of the Biginelli reaction with click chemistry has been used for the one-pot synthesis of 1,2,3-triazole linked
dihydropyrimidinones from azides, aromatic aldehydes containing a propargyl ether group, urea, and 1,3-dicarbonyl compounds
using Cu(OAc)2/sodium ascorbate as catalyst in acetic acid under mild reaction conditions. 相似文献
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Zeinab Noroozi TissehFereshteh Ahmadi Minoo DabiriHamid Reza Khavasi Ayoob Bazgir 《Tetrahedron letters》2012,53(28):3603-3606
A practical, simple, and efficient method for the synthesis of pyrano-fused spirooxindoles via an organocatalytic three-component reaction of isatins, malononitrile, and dialkyl acetylenedicarboxylate in the presence of 3,4-dimethylaniline as an organocatalyst in ethanol is reported. The structures of these products are confirmed by IR, 1H NMR and 13C NMR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction studies. 相似文献
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Novel thiono and seleno phosphoramidate compounds with the general formula (X)(Y)P(C6H5)2; (X = NMe2 & Y = S, 1a; X = NEt2 & Y = S, 2a; X = NMe(CH2Ph) & Y = S, 3a; X = NH(CH2Ph) & Y = S, 4a; X = NEt(CH2Ph) & Y = S, 5a; X = N(C(Me)3) (CH2Ph) & Y = S, 6a; X = N(CH2Ph)2 & Y = S, 7a; X = NMe2 & Y = Se, 1b; X = NEt2 & Y = Se, 2b; X = NMe(CH2Ph) & Y = Se, 3b; X = NH (CH2Ph) & Y = Se, 4b; X = NEt(CH2Ph) & Y = Se, 5b; X = N(C(Me)3)(CH2Ph) & Y = Se, 6b and X = N(CH2Ph)2 & Y = Se, 7b) were prepared and characterized by 1H, 31P and 13C NMR and IR spectroscopy and elemental analysis. 31P chemical shift of thiono and seleno derivatives didn’t show significant different because of their little difference in
electronegativity sulfur and selenium. Hydrophobic parameter of compounds was determined by measurement of octanol-water partition
coefficient by shake-flask technique. Determination of human erythrocyte acetylcholinesterase (hAChE) activity was carried
out according to the Ellman’s modified kinetic method. IC50 values of the selected thiono and seleno compounds varied from 3.4 to 0.11 and 9.9 to 5.1 mM, respectively. The seleno compounds
show lower affinities for hAChE relative to the thino compounds. These results demonstrate that hydrophobic and electronic
factors of the organophosphorus compounds play a key role on the inhibitory potency. 相似文献
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Mahdi Mirzaei Hossein Eshghi Mohammad Rahimizadeh Mehdi Bakavoli Maryam M. Matin Minoo Hosseinymehr Hadi Amiri Rudbari Giuseppe Bruno 《中国化学会会志》2015,62(12):1087-1096
A series of α‐aminophosphonates were synthesized through one‐pot condensation of aryl aldehydes, aryl amines and diethyl phosphite in the absence of any catalyst and organic solvents. All the synthesized α‐aminophosphonates were characterized by spectral and elemental analysis and in the case of compound 4j by X‐ray crystallography. Some of these new α‐aminophosphonate derivatives were found to have cytotoxic activity on the cancer cell line DU145 in vitro by the MTT method. 相似文献