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0.2%α-吡喃酮WP对植物病原真菌的防治效果 总被引:2,自引:1,他引:2
0.2%α-吡喃酮WP的有效成分为5,6-二氢-6-戊基-2H-吡哺-2-酮(5,6-dihydro-6-pentyl-2H-pyran-2-one)。采用菌丝速率法测定了0.2%阻吡喃酮WP的抗菌谱,含药浓度20gg/ml的PDA培养基对测试的11种植物病原真菌均有抑制作用,其中对禾谷丝核菌的抑制作用最强,抑制率为89.3%。温室条件下用干种子量0.5%的0.2%阻吡喃酮WP拌种处理对小麦纹枯病的防治效果达61.6%,对棉花立枯病的防治效果达85.6%,较于种子量1%的40%多菌灵拌种处理防治效果分别提高了14.6%和17.9%。 相似文献
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Mohamed E. I. Badawy 《应用聚合物科学杂志》2010,117(2):960-969
In the present work, quaternary chitosans as water‐soluble compounds were prepared based on three‐step process. Schiff bases were firstly synthesized by the reaction between the amino groups of chitosan with aliphatic aldehydes followed by a reduction with sodium borohydride (NaBH4) to form N‐(alkyl) chitosans. N,N,N‐(dimethyl alkyl) chitosans were then obtained by a reaction of chitosan containing N‐butyl, N‐pentyl, N‐hexyl, N‐heptyl, and N‐octyl substituents with methyl iodide. The compounds were characterized using IR and NMR spectroscopy. Subsequent experiments were conducted to test their antimicrobial activities against the most economic plant pathogenic bacteria of crown gall disease Agrobacterium tumefaciens, soft mold disease Erwinia carotovora, fungi of grey mold Botrytis cinerea, root rot disease Fusarium oxysporum, and damping off disease Pythium debaryanum. Quaternary chitosans enhanced the antibacterial activity and N,N,N‐(dimethyl pentyl) chitosan was the most active one with Minimum Inhibitory Concentration (MIC) of 750 and 1225 mg/L against A. tumefaciens and E. carotovora, respectively. All quaternized chitosans gave stronger antifungal activities than chitosan where N,N,N‐(dimethyl pentyl) chitosan and N,N,N‐(dimethyl octyl) chitosan were significantly the highest in mycelial growth inhibiation against B. cinerea (EC50 = 908 and 383 mg/L, respectively), F. oxysporum (EC50 = 871 and 812 mg/L, respectively), and P. debaryanum (EC50 = 624 and 440 mg/L, respectively). In addition, spore germination of B. cinerea and F. oxysporum was significantly affected with the compounds at the tested concentrations and the inhibition activity was increased with an increase in the chain length of the alkyl substituent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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A series of six photo-crosslinkable thermotropic liquid crystalline copolyesters were prepared by polycondensation method at room temperature using tetra-n-butylammonium bromide as the phase transfer catalyst. The diacid chloride involved in this process was adipoyl chloride, the common diol (diol-1), also referred to as bischalcone diol, used was 3,3′-benzene-1,4-diylbis[1-(4-hydroxyphenyl)prop-2-en-1-one] and six different arylidene diols were involved as varying diols (diol-2), in the ratio 2:1:1. The common diol and the six arylidene diols were synthesized by the acid-catalyzed Claisen-Schmidt synthesis. The inherent viscosity ηinh of these six copolyesters was found between 0.35 and 0.45. The microstructure of the repeating unit present in the copolyester chain was confirmed by FT-IR, 1H–NMR and 13C–NMR spectroscopic techniques. Thermal transition temperatures, resolved from the DSC thermograms, were found to be well above room temperature. Optical polarizing microscopy was employed to establish the liquid crystalline property and all the polymers were found to have nematic phase. The photo-crosslinking behaviour of these copolyesters was studied in DMF solution at different time intervals. The copolyesters having methoxy group in them absorb UV-A rays (315–400 nm) for a longer duration, which promotes them to be good candidates for UV filters and sunscreens. 相似文献
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基于药效团拼合原理设计并合成23个未见文献报道的 (E)-4-[3-(2-溴苯基)丙烯酰基]苯基-取代苯磺酸酯衍生物(产率:60.9-80.3%),通过1HNMR、MS、13CNMR确证了产物结构,采用MTT法以5-氟尿嘧啶和伊马替尼为阳性对照药,以人宫颈癌Hela细胞、人肺癌A549细胞和人慢性粒细胞白血病K562细胞为测试细胞株评价了目标化合物的体外抗肿瘤活性。目标化合物Ⅴp表现出最强的A549细胞增殖抑制活性(半抑制浓度IC50 = 7.53 μmol/L),优于阳性对照药5-氟尿嘧啶(IC50 = 8.1 μmol/L),目标化合物Ⅴt表现出最强的K562细胞增殖抑制活性(IC50 = 4.47 μmol/L),目标化合物Ⅴd表现出最强的Hela细胞增殖抑制活性(IC50 = 4.53 μmol/L),比阳性对照药5-氟尿嘧啶(IC50 = 13.5 μmol/L)强约3倍。目标化合物Ⅴd对A549细胞(IC50 = 8.0 μmol/L)和K562细胞(IC50 = 7.81 μmol/L)也表现出强的增殖抑制活性,值得进一步深入研究。 相似文献
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Qiu Zhao Gang Wang Fuxia Liao Yifan Sha Fei Xu Chunshan Li Zengxi Li Yijun Cao 《中国化学工程学报》2021,33(5):160-166
An ionic liquid(IL) catalyzed solvent-free process was developed for the direct synthesis of chalcone and its derivatives by using substituted acetophenones and benzaldehydes via aldol reaction under mild conditions. A series of acidic and basic ILs were selected and screened. The influences of cations and reaction conditions on product yield and selectivity were systematically investigated. The [Bmim]OH was identified as the optimal IL, with the highest yield and selectivity reaching up to 96.7% and 100%, respectively. A reaction mechanism-based kinetic model was established and regressed with experimental data, revealing the b-Hydroxylketone dehydrolysis with activation barrier of 37.8 k J·mol~(-1) was observed as the ratecontrolling step. 相似文献
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I. V. Rybitskaya A. G. Shmakov O. P. Korobeinichev 《Combustion, Explosion, and Shock Waves》2007,43(3):253-257
The propagation velocities of propane-air and methane-air flames of various compositions with and without the addition of
600 ppm trimethyl phosphate were measured and calculated. The flame propagation velocity was determined using the heat flux
method, which allows a flame to be stabilized on a flat burner under nearly adiabatic conditions. The experimental results
were compared with flame propagation velocities calculated using the PREMIX and CHEMKIN codes for the Westbrook mechanism
for the destruction of trimethyl phosphate and the Curran mechanism for hydrocarbon oxidation. The methane-air flame was modeled
using the GRI 3.0 mechanism.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 3, pp. 9–14, May–June, 2007. 相似文献
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Six new poly(amid‐imide)s containing chalchone and hydantoin moieties in the main chain were synthesized through the polycondensation reaction of 1,3‐bis[4,4′‐bis(trimellityimido)phenyl]‐2‐propenone 6 with six hydantoin derivatives 7a‐f in a medium consisting of triphenyl phosphite, calcium chloride, pyridine, and N‐methyl‐2‐pyrrolidone. The polycondensation reaction produced a series of novel poly(amid‐imide)s 8a‐f in high yields with inherent viscosities between 0.26 and 0.42 dL/g. The resulting polymers were characterized by elemental analysis, viscosity measurements, solubility test, thermo gravimetric analysis (TGA and DTG), FTIR, and UV‐Vis spectroscopy. 1,3‐bis[4,4′‐bis(trimellityimido)phenyl]‐2‐propenone 6 was prepared from a three‐step reaction by using 4‐nitro benzaldehyde 1 and 4‐nitro acetophenone 2 as precursors. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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Martin Danko Anita AndicsCsaba Kosa Pavol HrdlovicDaniel Vegh 《Dyes and Pigments》2012,92(3):1257-1265
Novel chalcones (3-phenyl-1-phenylprop-2-en-1-ones) substituted on one end (position 3) with electron donating diphenylaminophenyl substituent and on the other end (position 1) with thiophenes with variable electronic effects (CH-1-CH-5) were prepared. The spectral properties of these molecules in solvents such as chloroform, cyclohexane, acetonitrile, methanol and incorporated into polymer matrices of polystyrene (PS), poly(methyl methacrylate) (PMMA) and poly(vinyl chloride) (PVC) were compared with those of 3-[4-(N,N-dimethylamino)-phenyl]-1-phenylprop-2-en-1-one (CH-1m) and 3-[4-(N,N-dimethylamino)phenyl]-1-(4-nitrophenyl)prop-2-en-1-one (CH-2m). The longest wavelength absorption band of model chalcones CH-1m and CH-2m was in the range of 400-420 nm and did not appear to be influenced by the medium. The fluorescence increased with the addition of acetonitrile, while it was effectively quenched in methanol. The strong electron-attracting nitro group quenched the fluorescence of CH-2m in nearly all solvents. In contrast, the fluorescence became more intense when the molecule was incorporated in a polymer matrix. The longest wavelength absorption band of novel chalcones was observed in the range of 410-450 nm in all media. The fluorescence of chalcones was red-shifted to the range of 530-575 nm and was most intense in chloroform. The quantum yield of fluorecence was the highest in chloroform for the chalcone with a methyl-thiophene (0.49) and low for the chalcone with a fluorenyl-thiophene group (0.07). The fluorescence of all chalcones (CH-1-CH-5) was effectively quenched in polar acetonitrile and methanol, and was less intense relative to chloroform when incorporated into a polymer matrix and more intense relative to other solvents. The lifetime of fluorescence was in the range of 1-4 ns. The Stokes shift was in the range of 4000-5000 cm−1 in chloroform, and lower in all other media. The spectral behavior of model chalcones CH-1m and CH-2m and novel chalcones with diphenylamino substituents was similar, producing observable fluorescence in several polymer matrices. The effect of the solvent on the fluorescence is discussed in terms of negative and positive solvatokinetic effects. 相似文献
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Cellulose derivatives containing long hydrocarbon side chains and the carbazole chromophore are prepared. N‐4′‐Bromobutylcarbazole is first synthesized from carbazole and 1,4‐dibromobutane. Alkylated carbazole is then reacted with cellulose acetate in dimethyl sulfoxide solution to produce cellulose ethers containing the desired chromophore. Polymers containing a mixture of alkyl side chains are also prepared by the subsequent addition of 1‐bromododecane to the reaction mixture. Characterization of the resulting cellulose derivatives by FTIR spectroscopy indicates that the deacetylation of cellulose acetate and the subsequent etherification are both complete. In addition, the incorporation of the carbazole chromophore is clearly shown by 1H‐ and 13C‐NMR spectroscopy. Polymers of different carbazole content, ranging from 2.9 to 1.1 chromophores per anhydroglucose repeat unit, are obtained by varying the reaction conditions. Substitution is found to be controlled primarily by the quantity of alkylating agent introduced while variation of the reaction time has little effect. This method is used to prepare (dodecyl)y(N‐4′‐carbazolylbutyl)xcellulose, (decyl)y(N‐4′‐carbazolylbutyl)xcellulose, and (butyl)y(N‐4′‐carbazolylbutyl)xcellulose. Cellulose acetate can be replaced by (methyl)cellulose as the starting material to obtain analogous products. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2764–2772, 1999 相似文献
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在实验室条件下,分别测定了1.5%卡松对棉花枯萎病菌、棉花红腐病菌、棉花红粉病菌、棉花黄萎病菌和棉花疫病菌等5种重要植物病原真菌及水稻白叶枯病菌、大白菜软腐病菌等两种重要植物病原细菌的抑制活性。结果表明,1.5%卡松对棉花枯萎病菌的MIC和EC50分别为40mg/L和9.2034mg/L,对棉花红腐病菌的MIC和EC50分别为40mg/L和0.7845mg/L,对棉花红粉病菌的MIC和EC50分别为20mg/L和0.6951mg/L,对棉花黄萎病菌的MIC和EC50分别为20mg/L和2.8383mg/L,对棉花疫病菌的MIC和EC50分别为2mg/L和0.3459mg/L;对水稻白叶枯病菌和大白菜软腐病菌的MIC分别为1mg/L和10mg/L;说明该药剂对供试7种植物病原菌均具有良好的抑制活性,尤以对棉花疫病菌和水稻白叶枯病菌的抑制活性较强。 相似文献
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The functional diamines 3,3′‐diaminochalcone and bis(3‐aminophenyl)‐3,5‐bis(trifluoromethyl)phenyl phosphine oxide were successfully prepared by simple and convenient procedures with short reaction times, and the overall yields were 78 and 70%, respectively. Copolyimides prepared from 3,3′‐diaminochalcone, bis(3‐aminophenyl)‐3,5‐bis(trifluoromethyl)phenyl phosphine oxide, and 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride exhibited excellent solubility in several organic solvents, such as dimethyl sulfoxide, N,N‐dimethylformamide, N‐methyl pyrrolidone, tetrahydrofuran, and acetone. They also showed very good thermal stability even up to 450°C for 5% weight loss (by thermogravimetric analysis) in nitrogen and a high glass‐transition temperature up to 274°C (by differential scanning calorimetry) in nitrogen. The copolymers' adhesive and photoreactive properties were also investigated, and it was confirmed that the copolyimide containing chalcone and phosphine oxide moieties in the main chain had good adhesiveness and photoreactivity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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《Catalysis communications》2008,9(2):315-316
In the presence of SOCl2/EtOH as a catalyst, various substituted chalcones are synthesized by aldol condensation. The HCl is generated in situ by the reaction of SOCl2 with absolute ethanol. 相似文献