96898-37-2Relevant articles and documents
Synthesis and antibacterial evaluation of 3,5-Diaryl-1,2,4-oxadiazole derivatives
Cunha, Felipe S.,Nogueira, Joseli M. R.,De Aguiar, Alcino P.
, p. 2405 - 2416 (2018/10/20)
This manuscript reports the synthesis of twenty 3,5-diaryl-1,2,4-oxadiazole derivatives, nine of which are novel compounds. The amidoxime reaction with acyl chlorides obtained from substituted benzoic acids was used. All compounds were tested against five standard (American Type Culture Collection (ATCC)) bacteria: Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Proteus mirabilis and Staphylococcus aureus. Screening assays were carried out using agar-diffusion technique, in which 100 μM heterocyclic compounds solutions (20percent dimethylsulfoxide/water) were employed. The minimum inhibitory concentrations (MIC) of the active compounds were determined by serial dilutions at decreasing concentrations in microtiter plates. The nitrated derivatives gave the best test results, where MIC = 60 μM (E. coli) was the lowest value found for an ortho-nitrated derivative. The activity of these compounds possibly involves a mechanism via free radicals. S. aureus and P. aeruginosa were resistant to all compounds.
CYCLIZATION AND ACID-CATALYZED HYDROLYSIS OF O-BENZOYLBENZAMIDOXIMES
Grambal, Frantisek,Lasovsky, Jan
, p. 2786 - 2797 (2007/10/02)
Kinetics of formation of 1,2,4-oxadiazoles from 24 substitution derivatives of O-benzoylbenzamidoxime have been studied in sulphuric acid and aqueous ethanol media.It has been found that this medium requires introduction of the Hammett H0 function instead of the pH scale beginning as low as from 0.1percent solutions of mineral acids.Effects of the acid concentration, ionic strength, and temperature on the reaction rate and on the kinetic isotope effect have been followed.From these dependences and from polar effects of substituents it was concluded that along with the cyclization to 1,2,4-oxadiazoles there proceeds hydrolysis to benzamidoxime and benzoic acid.The reaction is thermodynamically controlled by the acid-base equilibrium of the O-benzylated benzamidoximes.