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81.
82.
通过1-苯基-3-(4-甲基苯基)-4-甲酰基吡唑与芳氧乙酰肼的加成反应,合成了5个新型的吡唑腙类化合物(3a~3e);3在酸性条件下环合,合成了5个新型的吡唑双杂环化合物(4a~4e). 3和4的结构经1H NMR,IR,MS和元素分析表征.对3和4分别进行了棉花枯萎病菌(A),棉花黄萎病菌(B),棉花立枯病菌(C),瓜果腐霉病菌(D),番茄早疫病菌(E)及向日葵菌核病菌(F)等初步的抑菌活性测试.结果表明,4的抑菌效果明显高于3;其中4d和4e对A,C和D的抑制率大于90%,对E和F的抑制率大于80%. 相似文献
83.
Haritosh Mishra 《Journal of organometallic chemistry》2006,691(16):3545-3555
New series of half-sandwich ruthenium(II) complexes supported by a group of bidentate pyridylpyrazole and pyridylimidazole ligands [(η6-C6H6)Ru(L2)Cl][PF6] (1), [(η6-C6H6)Ru(HL3)Cl][PF6] (2), [(η6-C6H6)Ru(L4)Cl][PF6] (3), and [(η6-C6H6)Ru(HL5)Cl][PF6] (4) [L2, 2-[3-(4-chlorophenyl)pyrazol-1-ylmethyl]pyridine; HL3, 3-(2-pyridyl)pyrazole; L4, 1-benzyl-[3-(2′-pyridyl)]pyrazole; HL5, 2-(1-imidazol-2-yl)pyridine] are reported. The molecular structures of 1-4 both in the solid state by X-ray crystallography and in solution using 1H NMR spectroscopy have been elucidated. Further, the crystal packing in the complexes is stabilized by C-H?X (X = Cl and π), N-H?Cl, and π-π interactions. 相似文献
84.
Comparative characterization of thermal isomerization rates of 6‐phenyl‐1,5‐diazabicyclo[3.1.0]hexane at convection and microwave heating
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Tatiana A. Kornilova Rafael R. Kostikov Alexander F. Khlebnikov Igor G. Zenkevich 《Journal of Physical Organic Chemistry》2018,31(7)
Rate constants of thermal isomerization of 6‐phenyl‐1,5‐diazabicyclo[3.1.0]hexane into 1‐(benzyl)‐4,5‐dihydro‐1H‐pyrazole at convection and microwave heating in toluene and chlorobenzene (solvents) were determined within the temperature range 90°C to 120°С. These data were used for the calculation of activation parameters of isomerization. It is shown that microwave heating increases the rate constants at the same temperature by a factor of 2 to 2.5 as compared with those using convection heating. The reason is that the effective temperature of microwave heating exceeds that of convection heating by 6°C to 9°С in toluene and by 12°C to 20°С in chlorobenzene as solvent. 相似文献
85.
The bi-functional carbamoyl methyl pyrazole ligands, C5H7N2CH2CONBu2 (L1), C5H7N2CH2CONiBu2 (L2), C3H3N2CH2CONBu2 (L3), C3H3N2CH2CONiBu2 (L4) and C5H7N2CH2CON(C8H17)2 (L5) were synthesized and characterized by spectroscopic and elemental analysis methods. The selected coordination chemistry of L1 to L4 with [UO2(NO3)2 · 6H2O], [La(NO3)3 · 6H2O] and [Ce(NO3)3 · 6H2O] has been evaluated. Structures for the compounds [UO2(NO3)2 C5H7N2CH2CONBu2] (6) [UO2(NO3)2 C5H7N2CH2CONiBu2] (7) and [Ce(NO3)3{C3H3N2CH2CONiBu2}2] (11) have been determined by single crystal X-ray diffraction methods. Preliminary extraction studies of the ligand L5 with U(VI) and Pu(IV) in tracer level showed an appreciable extraction for U(VI) and Pu(IV) up to 10 M HNO3 but not for Am(III). Thermal studies of the compounds 6 and 7 in air revealed that the ligands can be destroyed completely on incineration. 相似文献
86.
A series of novel bispyrazoles joined by arylmethylene at C‐4 position were synthesized with aromatic aldehydes obtained from lignin and screened for their in vitro antioxidant activities by N,N‐diphenyl‐N′‐picrylhydrazyl (DPPH) and 2,2′‐azino‐bis(3‐ethylenzothiazoline‐sulphonic acid) diammonium salt (ABTS+) radical scavenging assays. All of these compounds exhibited good DPPH and ABST+ radical scavenging activities as compared to the standard, Trolox, which suggested their potential as promising agents for curing tumors or other free radical‐related diseases. 相似文献
87.
《Journal of Coordination Chemistry》2012,65(4):423-430
A new 1-D cadmium(II) mixed ligand dimer supramolecular ladder [Cd2 L 4(3,5-DNBA)2]H2O (1), (L?=?3-(2-pyridyl)pyrazole and 3,5-DNBA?=?3,5-dinitrobenzoate) was synthesized by hydrothermal methods. X-ray structural analysis of complex 1 revealed that two cadmium(II) cores are bridged by two deprotonated pyrazole groups of L, leading to dinuclear cadmium(II) [Cd2 L 4(3,5-DNBA)2]. The dimers are joined by hydrogen-bonding interactions between two different cadmium(II) dimers to form a one-dimensional ladder-like framework and stabilized by weak π–π interactions. Moreover, the fluorescence spectrum of compound 1 exhibits blue fluorescent emission in the solid state at room temperature. 相似文献
88.
1 INTRODUCTIONInrecentyears ,triazolo[3,4, b] 1 ,3,4 thiadiazolederivativeshavebeenat tractingmuchattentionfromchemistsandpharmacologistsbecausetheyshowbroadspectraofbiologicalactivities,suchasinsecticidal[1 ] ,antifungal[2 ] ,herbicidal[3] ,an tibacterial[4] ,hypotensiv… 相似文献
89.
Yassine Kaddouri Redouane Benabbes Sabir Ouahhoud Magda Abdellattif Belkheir Hammouti Rachid Touzani 《Molecules (Basel, Switzerland)》2022,27(9)
Bayoud disease affects date palms in North Africa and the Middle East, and many researchers have used various methods to fight it. One of those methods is the chemical use of synthetic compounds, which raises questions centred around the compounds and common features used to prepare targeted molecules. In this review, 100 compounds of tested small molecules, collected from 2002 to 2022 in Web of Sciences, were divided into ten different classes against the main cause of Bayoud disease pathogen Fusarium oxysporum f. sp. albedinis (F.o.a.) with structure–activity relationship (SAR) interpretations for pharmacophore site predictions as (δ−···δ−), where 12 compounds are the most efficient (one compound from each group). The compounds, i.e., (Z)-1-(1.5-Dimethyl-1H-pyrazole-3-yl)-3-hydroxy but-2-en-1-one 7, (Z)-3-(phenyl)-1-(1,5-dimethyl-1H-pyrazole-3-yl)-3-hydroxyprop-2-en-1-one 23, (Z)-1-(1,5-Dimethyl-1H-pyrazole-3-yl)-3-hydroxy-3-(pyridine-2-yl)prop-2-en-1-one 29, and 2,3-bis-[(2-hydroxy-2-phenyl)ethenyl]-6-nitro-quinoxaline 61, have antifungal pharmacophore sites (δ−···δ−) in common in N1---O4, whereas other compounds have only one δ− pharmacophore site pushed by the donor effect of the substituents on the phenyl rings. This specificity interferes in the biological activity against F.o.a. Further understanding of mechanistic drug–target interactions on this subject is currently underway. 相似文献
90.
1,1'-Diacetoacetylferrocene 1 reacted with phenylene-1,3-dioxyactyl hydrazine 2 in absolute ethanol to give the macrocyclic ferrocenyl dipyrazole compound in moderate yield. Determined by X-ray structure analysis, it crystallizes in monoclinic system, space group P21/c with a = 13.7509(4), b = 8.1277(2), c = 21.7472(6) , β = 103.1030(10)°, V = 2367.25(11) 3, Z = 4, Dc = 1.505 g/cm3, R = 0.0353 and wR = 0.0811. The electrochemical studies reveal that redox of Fe+/Fe in ferrocene is a reversible one-electron process. 相似文献