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101.
The title compound2-p-methyloxyphenyl-3a-(2-phenyl-1,2,3-triazole-4-yl)-3,4- dihydro-1,2,4-oxa-diazolo[4,5-d][1,5] benzothiazepine (C31H25N5O2S, Mr = 531.63) has been syn- thesized and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1 with a = 10.888(2), b = 15.115(3), c = 16.702(3), α = 99.90(3), β = 95.21(3), γ = 100.41(3)o, V = 2642.1(9) nm3, Dc = 1.336 g/cm3, Z = 4, F(000) = 1112, μ = 0.162 mm-1 ,λ(MoKα) = 0.071073 nm, R = 0.0357 and wR = 0.1126 for 10620 observed reflections with I > 2σ(I). X-ray analysis reveals that the molecular backbone consists of a tricyclic system with the central seven- membered ring in a twisted boat-like conformation. 相似文献
102.
In this study, eight new compounds derived from thiophene were synthesised and characterised. The four symmetrical compounds contain two heterocyclic 1,2,4- oxadiazole on each side of the 2,5-disubstituted thiophene, and the four non-symmetrical compounds contain alkyne groups as a spacer replacing one of these heterocycles. Some of the compounds presented liquid crystalline properties with smectic and nematic mesophases. The non-symmetrical compounds presented low emission of blue light. 相似文献
103.
异噁唑衍生物作为一类重要的生物活性物质,其合成一直受到人们的关注,其中德国HMR公司开发研制的新型抗内风湿性关节炎药来氟米特(Leftunomide)已于1998年在美国率先上市,该药还具有很好的免疫调节作用.7H-均三唑[3,4-b]-1,3,4-噻二嗪、咪唑并[2,1-b]噻唑和咪唑并[2,1-b]-1,3,4-噻二唑衍生物均表现出广谱的生物活性. 相似文献
104.
Fariba Saadati Babak Kaboudin Rana Hasanloei Zeinab Namazifar Xavier Marset Gabriela Guillena 《应用有机金属化学》2020,34(10):e5838
The easy synthesis of graphene oxide (GO)-supported manganese dioxide (MnO2) nanoparticles as a stable heterogeneous nanocatalyst (MnO2@GO) is described. This catalyst was investigated in the synthesis of 1,2,4-oxadiazoles from amidoximes and aldehydes via a cyclization and oxidation process. The nanocomposite was prepared and characterized using various techniques. The catalytic application of the nanocomposite was examined in the reaction of a variety of aldehydes with aliphatic and aromatic amidoximes. The stable and robust catalyst was recycled for seven consecutive runs without a significant decrease in the catalytic activity. 相似文献
105.
We have designed and synthesized a small library of 3,5-disubstituted-1,2,4-oxadiazole containing combretastatin A-4 (CA-4) analogs. Our objective is to increase the efficacy of the CA-4 as an anti-tubulin and antimitotic agent by substituting the cis-alkene bond with one of its bioisosteres, the 1,2,4-oxadiazole ring. We also modified the substituents attached to both of the phenyl rings (ring A and B in Fig. 1) of CA-4 for the purpose of diversifying our analogs based on SAR. These compounds were synthesized via a coupling reaction between an amidoxime and a carboxylic acid in DMF solvent, with HOBt as a base, and utilizing EDCI as a coupling reagent. Using this protocol, we synthesized a small library of 10 compounds with moderate to good yields. A detailed biological study is currently undergoing in our laboratory to evaluate the activity of these compounds. 相似文献
106.
2-取代氨基-5-去氢枞基-1,3,4-噁二唑衍生物的合成及除草活性 总被引:2,自引:0,他引:2
以去氢枞酸为原料,经酰化后与水合肼反应合成去氢枞酰肼3,再与芳基异硫氰酸酯反应,得到中间体1-去氢枞酰基-4-取代基氨基硫脲4,4在Hg(OAc)2/EtOH条件下关环,合成得到一系列新型2-取代氨基-5-去氢枞基-1,3,4-噁二唑化合物5.采用IR,MS,1HNMR,13C NMR和元素分析等方法对中间体4和目标产物5进行了分析和表征.初步的除草活性测试表明,化合物4和5对油菜的胚根生长以及对稗草的幼苗生长有一定的抑制作用,其中化合物4d在浓度为100mg/L时对油菜胚根生长的抑制率达88.2%. 相似文献
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110.
为了寻求新型抗肿瘤药物,设计并合成了一系列新型1,3,4-噁二唑和1,3,4-噻二唑衍生物,对这些化合物在人类四种癌细胞:B-16(皮肤黑色素瘤细胞)、PC-3(人前列腺癌细胞)、U87(人原发性胶质母细胞瘤细胞)和A549(人非小细胞肺癌细胞)进行抗肿瘤活性评价.结果显示部分化合物具有较好的抗肿瘤活性,尤其是5-{6-[4-(2-羟基乙基)哌嗪-1-基]-2-甲基嘧啶-4-基氨基}-[1,3,4-噻二唑-2-羧酸(2-甲氧基苯基)酰胺(8b)]和5-{6-[4-(2-羟基乙基)哌嗪-1-基]-2-甲基嘧啶-4-基氨基}-[1,3,4-噻二唑-2-羧酸(4-甲氧基苯基)酰胺(8c)],对四种癌细胞都显示出较高的抗肿瘤活性,其抑制活性均优于阳性对照达沙替尼,随后对这类化合物抑制肿瘤的可能靶点开展了进一步研究. 相似文献