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61.
62.
A simple, efficient, and eco-friendly procedure was developed for the condensation of N-methylhydroxylamine hydrochloride
with benzaldehydes bearing electron-donating or electron-withdrawing substituents in the presence of powdered molecular sieves
(3 ?) in a solventless system. α-Aryl-N-methylnitrones are obtained in excellent yields (80–100%); similar aromatic ketones
do not react under these conditions, rendering the method chemoselective. 相似文献
63.
Various 2-arylbenzimidazoles were synthesized from o-phenylenediamine and aldehydes via one-step process using DMP (Dess-Martin-periodinane) reagent as an oxidant.The method was proved to be simple,convenient and the products were isolated with good yields(80-90%). 相似文献
64.
Priyanka G.Mandhane Ratnadeep S.Joshi Deepak R.Nagargoje Charansingh H.Gill 《中国化学快报》2011,22(5):563-566
An efficient synthesis of novelα-aminophosphonates by the reaction of aldehydes and amines with triethyl phosphite in the presence of the easily available,inexpensive,and nontoxic catalyst thiamine hydrochloride(VB1).This method affords theα-aminopho-sphonates under the influence of ultrasound irradiation in aqueous medium,in short reaction times(4-6 min),high yields(85-95%), with improved purity.The process is green,mild,inexpensive and excellent yields are the main compensation of this procedure. 相似文献
65.
An efficient and greener protocol for the synthesis of poly functionalized pyridines using tetra‐n‐butyl ammonium fluoride (TBAF) in water is established. Remarkable advantages of the present synthetic strategy over the others are shorter reaction times, higher isolated yields, reuse of catalytic system, simple work‐up procedure and more especially its applicability to heteryl and aliphatic aldehydes. 相似文献
66.
Jaiprakash N. Sangshetti ;Firoz A. Kalam Khan ;Rashmi S. Chouthe ;Manoj G. Damale ;Devanand B. Shinde 《中国化学快报》2014,25(7):1033-1038
A novel series of 5-((5-substituted-1H-1,2,4-triazol-3-yl)methyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridines 5(a–i) has been synthesized from thienopyridine hydrazide, substituted aromatic nitriles using 4-dimethylaminopyridine(DMAP) as a catalyst under microwave irradiation and evaluated for their in vitro antifungal activity. Compound 5g is found to be more potent against Candida albicans when compared with miconazole. Docking study of the newly synthesized compounds was performed, and results showed good binding mode in the active site of fungal enzyme P450 cytochrome lanosterol 14 ademethylase. ADMET properties of synthesized compounds were also analyzed and showed good drug like properties. The results of in vitro antifungal activity, docking study and ADMET prediction revealed that the synthesized compounds have potential antifungal activity and can be further optimized and developed as a lead compound. 相似文献
67.
Priyanka G. Mandhane 《Tetrahedron letters》2010,51(11):1490-939
We report a new environmentally-benign, convenient, and facile methodology for the synthesis of α-hydroxyphosphonates from an aromatic/heteroaromatic aldehyde with triethyl phosphite in the presence of potassium dihydrogen phosphate (KH2PO4) under ultrasound-assisted solvent-free conditions. Furthermore, a series of compounds were synthesized and characterized by melting point, EI-MS, NMR, and IR tools. Utilization of easy reaction conditions, isolation, and purification makes this manipulation very interesting from an economic perspective. 相似文献
68.
Suryakant B. Sapkal Kiran F. Shelke Bapurao B. Shingate Murlidhar S. Shingare 《中国化学快报》2010,21(12):1439-1442
<正>l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina(Al_2O_3) has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave irradiation to yield benzofuran derivatives. 相似文献
69.
The substituted warfarin acid chalcones have been prepared by condensation of warfarin acid and aromatic/aliphatic aldehyde using aq. NaOH as catalyst. The method is simple, cost‐effective and gives good yield in a short reaction time. All the compounds synthesized have been characterized by IR, NMR and Mass spectra. A new series of 4‐hydroxy‐3‐(3‐oxo‐1,5‐diaryl‐3‐oxo‐pent‐4‐enyl)‐chromen‐2‐ones were synthesized and submitted to biological activity. Result of the biological screening showed the compounds 3b , 3h being the most effective among the various treatments in antimicrobial screening. Compounds 3c , 3d , 3k and 3l showed moderate activity against the microorganisms tested. Compounds 3e , 3h have shown good antifungal activity. 相似文献
70.