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Synthesis, characterization and antifungal activity of some fluorine containing 1,3,5-trisubstituted pyrazoline derivatives

100%

Manivannan C. , Santhi N.

World News of Natural Sciences

2017

tom 10

86-94

A series of (E)-1-(4-fluorophenyl)-3-substitutedphenylprop-2-en-1-one (3-7) were ultrasonically prepared by the reaction of 4-fluoroacetophenone with different aromatic aldehydes in the presence of alkali . Reaction of the prepared chalcones (3-7) with 3,4,5-trimethoxybenzohydrazide (8) afforded the corresponding substituted pyrazoline (9-13). Ultrasonic irradiation method provides several advantages over current reaction methodologies, including a simple work-up procedure, shorter reaction times and good yields. All the prepared compounds have been characterized by FT-IR and 1H-NMR spectra. These compounds were screened for their antifungal activity using disc diffusion method. Compound 10 and 11 was found to exhibit the most potent in-vitro anti-fungal activity with against all the fungal strains.

Synthesis and characterization of 1,3,5-trisubstituted pyrazoline derivatives by ultrasonic irradiation method and evaluation of its antibacterial activity

86%

Raguraman A. , Santhi N.

International Letters of Chemistry, Physics and Astronomy

2014

tom Vol. 20, iss. 2

219--233

A series of novel 1,3,5-trisubstituted pyrazoline derivatives (P1-P10) have been synthesized by the reaction of substituted chalcones (C1-C10) with 4-hydroxybenzhydrazide. The starting material, chalcones were prepared by claisen Schmidt condensation of 4-methylacetophenone with substituted aldehydes in the presence of sodium hydroxide in ethanol. 4-hydroxybenzhydrazide was synthesized by condensing methyl 4-hydroxybenzoate with hydrazine hydrate. The cycloaddition of chalcones with 4-hydroxybenzhydrazide gives 1, 3, 5-trisubstituted pyrazoline derivatives. The structures of synthesized derivatives were confirmed by IR, 1HNMR and 13C NMR spectrum. The synthesized compounds were screened for their antibacterial and antifungal activity.

Synthesis, characterization and evaluation of mosquito larvicidal effect of 1,3,4-oxadiazole derivatives against Culex quinquefasciatus

86%

Santhanalakshmi K. , Kalyanasundharam S. , Muthukumar S. , Rosy P. J.

2018

tom 19

58-64

A new series of 1,3,4-oxadiazole derivatives were prepared from the condensation of acid hydrazide,5-bromo-2-(trifluoromethoxy)benzoic acid in POCl3 by ultrasonic irradiation method. The new synthetic method furnished the desired products in shorter time and good yields. The chemical structures of compounds 4a-h were confirmed by Fourier transform infrared spectroscopy (IR), proton nuclear magnetic resonance (1H-NMR), carbon nuclear magnetic resonance (13C-NMR) and elemental analyses. Larvicidal bioassay tests were performed using several 2-(5-bromo-2-(trifluoromethoxy) phenyl)-5-aryl-1,3,4-oxadiazole. These synthesized compounds presented strong larvicidal activity against urban mosquitoes Culex quinquefasciatus. The results suggest that larvicidal activity might be correlated with the presence of electron-withdrawing substituents in the para position of the phenyl ring. The alterations observed in the larvae spiracular valves of the siphon and anal papillae by 1,3,4-oxadiazoles in the larvicidal bioassay are responsible for larvae’s death.