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1.
The title compound 1-(4-chlorophenyl)-3-[5-(pyrid-4-yl)-1,3,4-thiadiazol-2-yl]urea (C14H10ClN5OS, Mr = 331.79) has been synthesized by the reaction of 2-amino-5-(pyrid-4-yl)- 1,3,4-thiadiazole with 4-chlorobenzoyl azide, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic system, space group P with a = 5.8550(8), b = 7.5668(10), c = 16.416(2) , α = 78.364(2), β = 81.204(2), γ = 84.749(2)°, V = 702.58(16) 3, Z = 2, Dc = 1.568 g/cm3, μ = 0.429 mm-1, F(000) = 340, the final R = 0.0442 and wR = 0.1092 for 2001 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that the title molecule is nearly planar. In the crystal structure, the molecules are linked by strong intermolecular N-H…N hydrogen bonds together with weak nonclassical intermolecular (C-H…Y, Y = N, O and Cl) hydrogen bonds and stacked through π-π interactions. The preliminary bioassay shows that the title compound exhibits good fungicidal activities against Rhizoctonia solani, Botrytis cinerea and Dothiorella gregaria.  相似文献   
2.
Four novel ON donor Schiff bases (E)-3-((4-phenoxyphenylimino)methyl)benzene-1,2-diol (HL1),(E)-3-((4-(4-biphenyloxy)phenyliminomethyl)benzene-1,2-diol (HL2), (E)-3-((4-naphthoxyphenylimino)methyl)benzene-1,2-diol (HL3), (E)-3-((4-(2-naphthoxy)phenylimino)methyl)benzene-1,2-diol (HL4) and their copper(II) complexes bis((E)-3-((4-phenoxyphenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L1)2) bis((E)-3-((4-(4-biphenyloxy)phenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L2)2), bis((E)-3-((4-naphthoxyphenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L3)2), bis((E)-3-((4-(2-naphthoxy)phenylimino)methyl)benzene-1,2-diol) copper(II) (Cu(L4)2) have been synthesized and characterized by spectroscopic (FTIR, NMR, UV–visible) and elemental analysis. The crystal structures of HL1, HL2, HL3, and HL4 have been determined, which reveal intramolecular N-H?O (HL1, HL2, HL3, and HL4) hydrogen bonds in the solid state. Keto-amine and enol-imine tautomerism is exhibited by the Schiff bases in solid and solution states. The Schiff bases and their copper(II) complexes have been screened for their biological activities. In antimicrobial assays (antibacterial and antifungal), HL4 showed promising results against all strains through dual inhibition property while the rest of the compounds showed activity against selective strains. On the other hand, in cytotoxic, DPPH, and inhibition of hydroxyl (OH) free radical-induced DNA damage assays, the results were found significantly correlated with each other, i.e. the ligands HL1 and HL2 showed moderate activity while their complexes Cu(L1)2 and Cu(L2)2 exhibited prominent increase in activity. As the results of these assays are supporting each other, it represents the strong positive correlation and antioxidant nature of investigated compounds.  相似文献   
3.
郝小江 《化学进展》2009,21(1):84-99
本文综述了我国特有的粉花绣线菊复合群7个变种化学与生物学研究,以新生物碱的发现为起点,从二萜与二萜生物碱化学结构、化学转化、化学合成、仿生合成与生源途径、植物化学分类与生物地理、生物活性等方面阐明了相关的科学问题,从宏观、微观层次形成了较系统的学术观点。  相似文献   
4.
大戟属植物在全世界分布有2000多种,对于本属植物二萜类成分及生物活性的综述报道较多,但是还未见关于三萜类化学成分及生物活性的综述报道。本文综述了该属植物各种类型三萜化合物(羊毛脂烷型、环阿尔廷烷型、大戟烷型、甘遂烷型、齐敦果烷型、乌苏烷型及羽扇豆烷型等)的化学性能以及抗肿瘤、抗炎抗菌、抗病毒等主要生物活性的研究。  相似文献   
5.
用一维1H、13C NMR谱、DEPT 13C NMR谱、选择性远程DEPT 13C NMR、1H-1H COSY和13C-1H COSY二维核磁共振技术研究了南海海绵Dysidea fragilis中的两个倍半萜herbadysidolide(1)和furodysinin lactone(2),确认了化学结构,并对其13C NMR和1H NMR谱进行了归属.药理活性试验表明:1和2具有一定的心血管活性.  相似文献   
6.
The title compound crystallizes in the monoclinic space group P21/c with unit cell parameters a = 3.8380(12), b = 11.994(4), and c = 16.245(5) Å, β = 90.743(5), V = 747.7(4) Å3, and Z = 4. The final reliability index is 0.0409 for 1088 observed reflections. All the non-hydrogen atoms in the title compound are almost coplanar, the largest deviation from the mean plane being 0.030(2) Å for atom C5. The crystal cohesion is accentuated by C–H⋅sN hydrogen bond. The X-ray crystallography analysis indicates that the methyl group is at the 5-position of the compound 4 rather than at the 7-position of the isomer 4-1. The preliminary biological test shows that the title compound has moderate herbicidal activity.  相似文献   
7.
大环二氢沉香呋喃吡啶类生物碱的结构及活性   总被引:3,自引:0,他引:3  
本文简要评述了近年来源于卫矛科植物中结构新颖的90个大环二氢沉香呋喃倍半萜吡啶类生物碱的结构类型,以及抗HIV及杀虫等生物活性。参考文献46篇。  相似文献   
8.
Abstract

A new γ-pyrone derivative, acrepyrone A (1), and three known sorbicillinoids, trichodimerol (2), dihydrotrichodimerol (3) and tetrahydrotrichodimerol (4) were isolated from an endophytic fungus, Acremonium citrinum SS-g13, harboured in the roots of the Chinese medicinal plant Fructus mori. Their structures were determined by analysing MS, NMR, and ECD data. Compound 1 was evaluated for its cytotoxic effect, antibacterial activity and quorum sensing inhibitory potential.  相似文献   
9.
Bacillus subtilis fmb60, which has broad-spectrum antimicrobial activities, was isolated from plant straw compost. A hybrid NRPS/PKS cluster was screened from the genome. Sixteen secondary metabolites produced by the gene cluster were isolated and identified using LC-HRMS and NMR. Three lipoamides D–F (1–3) and two amicoumacin derivatives, amicoumacins D, E (4, 5), were identified, and are reported here for the first time. Lipoamides D–F exhibited strong antibacterial activities against harmful foodborne bacteria, with the MIC ranging from 6.25 to 25 µg/mL. Amicoumacin E scavenged 38.8% of ABTS+ radicals at 1 mg/mL. Direct cloning and heterologous expression of the NRPS/PKS and ace gene cluster identified its importance for the biosynthesis of amicoumacins. This study demonstrated that there is a high potential for biocontrol utilization of B. subtilis fmb60, and genome mining for clusters of secondary metabolites of B. subtilis fmb60 has revealed a greater biosynthetic potential for the production of novel natural products than previously anticipated.  相似文献   
10.
李英俊  刘丽军  靳焜  孙淑琴  许永廷 《化学学报》2010,68(16):1577-1584
以4-氨基-5-[2-(4-氯苯氧甲基苯并咪唑)-1-亚甲基]-3-巯基-1,2,4-三唑(6)和不同的芳香酸为原料, 在三氯氧磷的作用下环化合成了17个新型3-[2-(4-氯苯氧甲基苯并咪唑)-1-亚甲基]-6-芳基-1,2,4-三唑[3,4-b]-1,3,4-噻二唑衍生物7. 利用IR, 1H NMR和元素分析对新化合物67的结构进行了表征. 初步的生物活性实验结果表明, 化合物7a7b在20 μg/mL时对大肠杆菌甲硫氨酰氨肽酶(EcMetAP1)具有较高的抑制活性, 抑制率分别为87.26%和82.62%, 化合物7f, 7h7l具有中等的抑制活性. 化合物7a7q在20 μg/mL时对细胞分裂周期(cdc25B)磷酸酯酶均具有抑制活性, 其中化合物7b, 7g7i在5 μg/mL时仍具有很高的抑制活性, 抑制率分别为98.76%, 83.87%和90.57%. 杀菌、杀虫、除草和植物生长调节活性筛选测定实验结果表明, 所测试的目标化合物7d7e, 7h7m7o7q均无活性.  相似文献   
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