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71.
Dubravka Matkovi‐alogovi Zora Popovi Vesna Trali‐Kulenovi Livio Racan Grace Karminski‐Zamola 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o190-o191
The title compound, C8H8N3S+·Cl−·2H2O, has been synthesized and characterized both spectroscopically and structurally. The structure consists of 1,3‐benzothiazole‐6‐carboxamidinium cations, chloride anions and water molecules, all interconnected by hydrogen bonds into a three‐dimensional network. The 1,3‐benzothiazole moiety is inclined to the 6‐amidine group by 36.71 (9)°. 相似文献
72.
Vesna Rastija Karolina Vrande
i Jasenka osi Gabriella Kaniai ari Ivana Maji Dejan Agi Domagoj ubari Maja Karna Drago Belo Mario Komar Maja Molnar 《Molecules (Basel, Switzerland)》2022,27(7)
Coumarin derivatives have been reported as strong antifungal agents against various phytopathogenic fungi. In this study, inhibitory effects of nine coumarinyl Schiff bases were evaluated against the plant pathogenic fungi (Fusarium oxysporum f. sp. lycopersici, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiourum). The compounds were demonstrated to be efficient antifungal agents against Macrophomina phaseolina. The results of molecular docking on the six enzymes related to the antifungal activity suggested that the tested compounds act against plant pathogenic fungi, inhibiting plant cell-wall-degrading enzymes such as endoglucanase I and pectinase. Neither compound exhibited inhibitory effects against two beneficial bacteria (Bacillus mycoides and Bradyrhizobium japonicum) and two entomopathogenic nematodes. However, compound 9 was lethal (46.25%) for nematode Heterorhabditis bacteriophora and showed an inhibitory effect against acetylcholinesterase (AChE) (31.45%), confirming the relationship between these two activities. Calculated toxicity and the pesticide-likeness study showed that compound 9 was the least lipophilic compound with the highest aquatic toxicity. A molecular docking study showed that compounds 9 and 8 bind directly to the active site of AChE. Coumarinyl Schiff bases are promising active components of plant protection products, safe for the environment, human health, and nontarget organisms. 相似文献
73.
Mervan Paši? Darko ?ubrini? Vesna ?upanovi? 《Bulletin des Sciences Mathématiques》2009,133(8):859-874
In order to measure fractal oscillatority of solutions at t=∞, we define oscillatory and phase dimensions of solutions of a class of second-order nonlinear differential equations. The relation between these two dimensions is found using formulas for box dimension of chirps and nonrectifiable spirals. Applications include the Liénard equation and weakly damped oscillators. 相似文献
74.
V. Y. Degoda V. M. Ogenko G. V. Vesna S. N. Naumenko 《Journal of Applied Spectroscopy》1998,65(2):258-262
We carry out a comparison between the luminescence spectra (photo-and x-ray luminescence) of porous silicon and disperse SiO2, which by its physical characteristics is most similar to oxide films on porous silicon. The photoluminescence of porous
silicon was also investigated using fluorescence (excitation by a nitrogen laser) and metallographic microscopes. We found
that the natures of the luminescence centers of porous silicon and disperse SiO2 are identical. A porous layer on single-crystal silicon ensures the creation of a highly branched surface of oxide film.
Luminescence centers are located on its inner (as viewed from the porous silicon) surface.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 2, pp. 247–251, March–April, 1998. 相似文献
75.
Vesna Kilibarda 《Semigroup Forum》2002,66(1):151-161
We obtain several new results about the coding of a monoid by an appropriate submonoid of a polycyclic monoid. In particular, we characterize groups, periodic monoids, and right cancellative monoids in terms of the coset decomposition of positively self-conjugate inverse submonoids of polycyclic monoids. 相似文献
76.
Eleven bis-ureas have been synthesized, and some of their properties are reported. Several of these compounds form supramolecular polymers in organic solvents. The self-association is shown by FTIR spectroscopy to display cooperativity at two levels. The first level of cooperativity is due to the synergistic association of the two urea functions of a single molecule. The second level of cooperativity is revealed by the fact that the formation of dimers is less favored than that of long oligomers. 相似文献
77.
78.
In this paper, using the context of complete partial metric spaces, some common fixed point results of maps that satisfy the generalized(φ, ψ)-weak contractive conditions are obtained. Our results generalize, extend, unify, enrich and complement many existing results in the literature. Example are given showing the validaty of our results. 相似文献
79.
Vesna Nikolić Mihajlo Stanković Ljubiša Nikolić Goran Nikolić Snežana Ilić-Stojanović Mirjana Popsavin Saša Zlatković Tatjana Kundaković 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(1-2):173-182
Molecular inclusion complexes of usnic acid (UA) with β-cyclodextrin (β-CD) and 2-hydroxypropyl β-cyclodextrin (HP β-CD) were prepared by the co-precipitation method in the solid state in the molar ratio of 1:1. Structural complexes characterization was based on different methods, FTIR, 1H NMR, XRD and DSC. Parallel to the complex by the above methods, corresponding physical mixtures of UA with cyclodextrins and complexing agents (β-CD, HP β-CD and UA) were analyzed. The results of DSC analysis showed that, at around 200 °C, the endothermal peak in the complexes with cyclodextrins originating from the UA melting has disappeared. Complex diffractogram patterns do not contain peaks characteristic for the pure UA. They are more appropriate to cyclodextrin diffractogram. This fact points to the molecular encapsulation of UA in the cyclodextrin cavity. Chemical shifts in 1H NMR spectra after the inclusion of UA into the cyclodextrin cavity, especially H-3 protons (0.0012 and 0.0102 ppm in the β-CD and HP β-CD, respectively) and H-5 and H-6 (0.0134 ppm) and hydrogen from CH3 (0.0073 ppm) HP β-CD also points to the formation of molecular inclusion complexes. The improved solubility of UA in water was achieved by molecular incapsulation. In the complex with β-CD the solubility is 0.3 mg/cm3, with HP β-CD 4.2 mg/cm3 while the uncomplexed UA solubility is 0.06 mg/cm3. The microbial activity of UA and both complexes was tested against eight bacteria and two fungi and during the test no reduced activity of UA in the complexes was observed. 相似文献
80.
Ivan M. Savic Vesna D. Nikolic Ivana M. Savic Ljubisa B. Nikolic Mihajlo Z. Stankovic 《Journal of Analytical Chemistry》2013,68(10):906-911
Green tea (Camellia sinensis) contains quercetin as a bioactive compound. Quercetin has anti-inflammatory and anticancer effects. The aim of this paper was to develop and validate an RP-HPLC method for determination of quercetin in green tea simpler and faster than other available methods. RP-HPLC analysis was performed by isocratic elution with a flow rate of 1.0 mL/min. Pure methanol was used as a mobile phase, while the quantification was effected at 370 nm. The separation was performed at 35°C using a C18 column (4.6 × 250 mm, 5 μm). The results showed that the peak area response is linear within the concentration range of 10–70 μg/mL (r = 0.9986). The values of LOD and LOQ were 1.2 and 4 μg/mL, respectively. For the intra-day and intra-instrument reproducibility, RSD were in the range of 0.05–0.84% and 0.89–1.55%, respectively. The results of accuracy for the different concentrations of quercetin (40, 50 and 60 μg/mL) were 101.3, 98.4, and 98.2%. The developed and validated method was successfully applied to the determination of quercetin in green tea extract. 相似文献