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81.
82.
《Journal of Saudi Chemical Society》2014,18(2):101-106
In the present investigation, a series of 2(4-pyridyl)-5[(aryl/heteroarylamino)-1-oxoethyl]thio-1,3,4-oxadiazole were synthesized using isonicotinohydrazide and substituted aryl/heteroaryl amines using pyridine as solvent. Newly synthesized compounds were tested for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system. Among the synthesized compounds, compounds 2(4-pyridyl)-5((2-nitrophenylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5e), 2(4-pyridyl)-5((4-nitrophenylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5g) and 2(4-pyridyl)-5((2-pyrrolylamino)-1-oxoethyl)thio-1,3,4-oxadiazole (5k) produced highest efficacy and exhibited >90% inhibition at a concentration of 0.0077, 0.0052 and 0.0089 μM, respectively. All the new compounds were pharmacologically evaluated for their in vitro Antimicrobial activity. 相似文献
83.
Reactions of (N-isocyanimino)triphenylphosphorane with aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) in the presence of aromatic (or heteroaromatic) carboxylic acids proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in good yields. The reaction proceeds smoothly and cleanly under mild conditions, and no side reactions were observed.
84.
85.
Ibrahim F. Nassar Saad R. Att-Allah Magdy M. Hemdan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):630-636
AbstractThe reaction of thiophene-2-carbonyl isothiocyanate with phenylhydrazine gave 1-phenyl-5-(thien-2-yl)-1,2,4-triazole-3-thiol which was transformed by follow-up reactions into derivatives substituted in the 3-position by 1,2,4-oxadiazole and 1,2,4-thiadiazole moieties via thioethers linkages. The antitumor activity of the products against two human tumor cell lines, namely hepatocellular carcinoma HePG-2 and mammary gland breast cancer MCF-7 as well as the antimicrobial activity of some of these compounds was evaluated. 相似文献
86.
AbstractA series of novel pyrethrin derivatives containing hydrazone and 1,3,4-oxadiazole thioether moieties were designed, synthesized, and evaluated for their insecticidal activity. Bioassays indicated that some of the target compounds exhibited good insecticidal activities against Plutella xylostella (P. xylostella), Vegetable aphids (V. aphids), and Empoasca vitis (E. vitis). In particular, compound (E)-2-((5-(2,2-dimethyl-3-(2-methylprop-1-en-1-yl)cyclopropyl)-1,3,4-oxadiazol-2-yl)thio)-N'-(4-(trifluoromethyl)benzylidene)acetohydrazide (6s) revealed excellent insecticidal activities against P. xylostella, V. aphids, and E. vitis with the 50% lethal concentration (LC50) values of 5.23, 7.07, and 1.61?mg/L, respectively, which were similar to or even better than those of chlorpyrifos, beta cypermethrin, spinosad, and azadirachtin. These results indicated that novel pyrethrin derivatives containing hydrazone and 1,3,4-oxadiazole thioether moieties could be developed as novel and promising insecticides. 相似文献
87.
A series of fluorescent liquid crystalline compounds containing 1,3,4-oxadiazole and benzo[b]thiophene units have been prepared. In CH2Cl2 solution, these compounds displayed a fluorescent emission with λmax at 422–426 nm and quantum yields of 41–48%. Most of them exhibited thermotropic liquid crystalline properties with nematic and/or smectic A phases with excellent thermal stability. This work revealed that longer terminal alkoxy chains would be detrimental to the formation of mesophases for such kind of compounds. The effect of the terminal groups on mesomorphic and spectroscopic property is discussed. 相似文献
88.
89.
在KOH作用下,芳甲酰肼1a~1e与CS2环化生成5-芳基-2-巯基-1,3,4-噁二唑(2a~2e);将2a~2e与氯乙酸乙酯反应,生成2-(5-芳基-1,3,4-噁二唑)硫基乙酸乙酯(3a~3e);3a~3e肼解得2-(5-苯基-1,3,4-噁二唑-2-硫基)乙酰肼(4a~4e);4a~4e与芳酰基异硫氰酸酯5a~5d反应得到双酰基氨基硫脲衍生物A1~A19;A1~A19在H2SO4催化下环合得到目标化合物B1~B19;目标化合物的结构经IR,1H NMR,MS,HRMS确证. 相似文献
90.
Abstract Two differently substituted crystalline 2,5-diphenyl-1,3,4-oxadiazole compounds are investigated in the pressure range up to 5GPa. Phase transitions are detected using Raman and X-ray investigations. 相似文献