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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.
In this study, a series of trifluoromethyl pyrimidine derivatives 5a-5v were designed and synthesized. All synthetic compounds were original. Bioassay results showed that some of the target compounds were proved to have higher antiviral and antifungal activities than those of commercial agents. Especially, EC50 values of the curative activity of compound 5j and the protection activity of compound 5m were 126.4 and 103.4 µg/mL, respectively, which were lower than that of ningnanmycin. Microscale thermophoresis experiment proved that there was a good interaction between compound 5m and TMV-CP. Meanwhile, the antifungal activity results showed that compound 5u had a significant on in vitro against Rhizoctonia solani (RS) activity, with the EC50 value of 26.0 µg/mL, which was equal to that of azoxystrobin. As well, in vivo experiments on rice leaves showed that compound 5u could effectively control RS, and the effect of 5u on the cell morphology of RS was observed by scanning electron microscopy.  相似文献   
3.
Root and flower essential oils of Cyanthillium cinereum (L.) H. Rob. (Synonym Vernonia cinerea (L.) Less.) (Asteraceae) collected in Southern Côte d’Ivoire was investigated using a combination of chromatographic and spectroscopic techniques. The root oil composition was dominated by trans–β–bergamotene (20.7%), β–elemene (19.0%), cyperene (10.6%), germacrene A (7.1%) and β–pinene (3.8%), whereas γ–humulene (31.0%), (E)–β–caryophyllene (17.0%), trans–β–bergamotene (7.7%), β–pinene (7.5%) and (E)–β–farnesene (6.0%) were the major components of flower oil. Two new compounds bearing the trans–β–bergamotene framework were identified: trans–β–bergamotenone and (E)–trans–β–bergamotenol.  相似文献   
4.
Seven new muurolane‐type sesquiterpenes, (4R,5R)‐muurol‐1(6),10(14)‐diene‐4,5‐diol (1), (4R,5R)‐muurol‐1(6)‐ene‐4,5‐diol (2), (4R,5R,10R)‐10‐methoxymuurol‐1(6)‐ene‐4,5‐diol (3), (4S)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (4), (4R)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (5), (6S,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (6), and (6R,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (7) were isolated from the marine sponge Dysidea cinerea. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D‐NMR, 2D‐NMR, and CD spectra as well as by comparing the NMR data with those reported in the literature. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
5.
A molecularly imprinted polymer was synthesized for the purpose of sinapic acid isolation from Egyptian nutraceutical Botrytis italica, L. (broccoli) due to its prominent medicinal and wide pharmacological activities. A computational study was first developed to determine the optimal template to functional monomer molar ratio. Based on the computational results, five polymers were synthesized using a bulk polymerization method with sinapic acid as the template molecule. Evaluation of the synthesized polymers binding performance was carried out using batch rebinding assay, which revealed that the molecularly imprinted polymer of molar ratio (1:4:20), template to functional monomer (4‐vinyl pyridine) to crosslinker (ethylene glycol dimethacrylate) was of optimum performance, thus, this polymer was applied for sinapic acid isolation from closely related analogues. This represents a more practical approach to isolate sinapic acid from different natural extracts selectively.  相似文献   
6.
对农作物重要病害灰霉病的致病菌——灰葡萄孢菌进行了代谢组提取溶剂、衍生化时间和温度等前处理条件以及内标物筛选优化。结果表明,以水杨苷作为内标物,试验条件下以甲醇-水(80∶20)为提取溶剂,按照4.0 m L/0.1 g菌丝的剂量进行提取,采用N,O-双(三甲基硅烷基)乙酰胺和甲氧基胺盐酸盐在37℃和6 h条件下进行衍生化,可实现多种代谢物衍生产物收率和稳定性的最优化。灰葡萄孢菌丝代谢组的检测获得了210个峰,其中50种代谢物与NIST 2008的匹配度达到80%以上,主要为氨基酸类、醇类、有机酸类、糖类等代谢物,并通过标准品对部分代谢物进行了定性。典型的17种代谢物在1.0~100μg/m L范围内线性关系良好,相关系数均大于0.98,检出限为0.02~10.0 ng/m L,定量下限为0.1~34.0 ng/m L。方法精密度分析结果显示89.05%代谢物的相对标准偏差为0.01%~16.8%。所建立的方法适合于丝状真菌的代谢组检测,可为农业和医学领域开展微生物代谢组研究提供参考。  相似文献   
7.
Vernonia cinerea Less. (ash-coloured fleabane; Asteraceae) is a widely distributed plant throughout India. The plant has reputation as folklore medicine in various traditional systems of medicine. The plant has been evaluated for varied pharmacological activities to validate its traditional claims, and has been scientifically reported to possess anti-inflammatory, antidiabetic, renoprotective, anticancer, antiviral, antimicrobial activities, etc. This review emphasises on ethnopharmacology and pharmacology of V. cinerea.  相似文献   
8.
Two labdane diterpenoids were isolated, from the resinous exudate of Haplopappus velutinus Remy (Asteraceae); the main compound was identified as 7,13-(E)-labdadien-15,18-dioic-acid-18-methyl ester (1) and the minor compound identified as 7-labden-15,18-dioic-acid-18-methyl ester (2). Their structures were obtained using FTIR, MS, HRMS and NMR data: 1D NMR (1H, 13C and DEPT-135), 2D homonuclear NMR (COSY and NOESY) and heteronuclear NMR (HSQC and HMBC). The trans stereochemistry of the decalin moiety of compounds 1 and 2 was established through NOESY experiments of the reduction product of 1; 7-labden-15,18-diol (1a). Diterpenoids 1 and 1a are described for the first time and showed antifungal activity, inhibiting approximately 40% mycelial growth of Botrytis cinerea.  相似文献   
9.
During the off-vine natural withering process of Erbaluce (white) grapes to obtain “Erbaluce Caluso” Passito wine, some berries change in color from green-yellow to blue. This phenomenon appears at different extents in different years and might be related to several parameters, such as temperature and humidity during withering, grape composition and Botrytis cinerea loading. To better understand the mechanism involved in color variation, the metabolic changes corresponding to this event were studied.  相似文献   
10.
1 ′,4′-Trans-diol of abscisic acid was isolated from botrytis cinerea as a colorless crystal. The molecular and crystal structures have been determined by X-ray diffraction analysis. It crystallizes in orthorhombic system, space group P212121 with a = 6.724(3), b = 17.559(6), c =12.265(2) (A), a = β = y = 90°, V = 1448.1(8) (A)3, Z = 4, Dx = 1.222 g/cm3, F(000) = 576 and μ(MoKa) = 0.087 mm-1. The final R = 0.0628 and wR = 0.1604 for 2501 independent reflections with Rint = 0.0160 and 1679 observed reflections with I >2σ(Ⅰ). There are three intermolecular hydrogen bonds in a unit cell.  相似文献   
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