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991.
Hasan Tunel Mustafa Er Hakan Alici Abdurrahman Onaran Tuncay Karakurt Hakan Tahtaci 《Journal of heterocyclic chemistry》2021,58(6):1321-1343
In this study, thioether-bridged imidazo[2,1-b][1,3,4]thiadiazole derivatives that contained both imidazole and 1,3,4-thiadiazole (compounds 7a-7i and 8a-8i ) were synthesized from the reactions of 2-amino-1,3,4-thiadiazole with phenacyl bromide ( 6a - 6i ) (at yields of 59% to 74%). The structure of the synthesized compounds was characterized using 1H NMR, 13C NMR, Fourier-transform infrared spectroscopy, elemental analysis, mass spectroscopy, and X-ray diffraction analysis. Mycelial growth, mycelial growth inhibition, minimum inhibitory concentration, minimum fungicidal concentration, and lethal dose values against various plant pathogenic fungi were determined for all of the target compounds synthesized in the study. The test results showed that most of the compounds had moderate to good antifungal activity. In addition, the absorption, distribution, metabolism, excretion (ADME) parameters of the compounds were calculated, and it was observed that all of the compounds met the drug-likeness rules in general. Finally, using docking simulations, it was found that compounds 7h , 7i , 8h , and 8i showed high affinity to PDB ID:5TZ1, which is an CYP51 antifungal target structure. 相似文献
992.
Amiri Delouei Amin Emamian Amin Karimnejad Sajjad Sajjadi Hasan Jing Dengwei 《Journal of Thermal Analysis and Calorimetry》2021,144(3):611-621
Journal of Thermal Analysis and Calorimetry - This study aimed at presenting a steady-state analytical solution for the two-dimensional heat conduction in a cylindrical segment made of functionally... 相似文献
993.
Mohammed Ghazwani M. Yasmin Begum Prawez Alam Mohammed H. Alqarni Hasan S. Yusufoglu Faiyaz Shakeel 《Molecules (Basel, Switzerland)》2021,26(11)
This article studies the solubility, Hansen solubility parameters (HSPs), and thermodynamic behavior of a naturally-derived bioactive thymoquinone (TQ) in different binary combinations of isopropanol (IPA) and water (H2O). The mole fraction solubilities (x3) of TQ in various (IPA + H2O) compositions are measured at 298.2–318.2 K and 0.1 MPa. The HSPs of TQ, neat IPA, neat H2O, and binary (IPA + H2O) compositions free of TQ are also determined. The x3 data of TQ are regressed by van’t Hoff, Apelblat, Yalkowsky–Roseman, Buchowski–Ksiazczak λh, Jouyban–Acree, and Jouyban–Acree–van’t Hoff models. The maximum and minimum x3 values of TQ are recorded in neat IPA (7.63 × 10−2 at 318.2 K) and neat H2O (8.25 × 10−5 at 298.2 K), respectively. The solubility of TQ is recorded as increasing with the rise in temperature and IPA mass fraction in all (IPA + H2O) mixtures, including pure IPA and pure H2O. The HSP of TQ is similar to that of pure IPA, suggesting the great potential of IPA in TQ solubilization. The maximum molecular solute-solvent interactions are found in TQ-IPA compared to TQ-H2O. A thermodynamic study indicates an endothermic and entropy-driven dissolution of TQ in all (IPA + H2O) mixtures, including pure IPA and pure H2O. 相似文献
994.
Bulut N Castillo JF Aoiz FJ Bañares L 《Physical chemistry chemical physics : PCCP》2008,10(6):821-827
Time-dependent real wave packet (RWP) and quasiclassical trajectory (QCT) calculations have been carried out to study the H(+) + LiH reaction on the ab initio potential-energy surface of Martinazzo et al. [J. Chem. Phys., 2003, 119, 11241]. Total initial state-selected and final state-resolved reaction probabilities for the two possible reaction channels, H(2)(+) + Li and LiH + H(+), have been calculated for total angular momentum J=0 at a broad range of collision energies. Integral cross sections and thermal rate coefficients have been calculated using the QCT method and from the corresponding J=0 RWP reaction probabilities by means of a capture model. The calculated thermal rate coefficients are found to be nearly independent of temperature in the 100-500 K interval with a value of approximately 10(-9) cm(3) s(-1), which is in good agreement with estimates used in evolutionary models of early-Universe lithium chemistry. The RWP results are found to be in good agreement overall with the corresponding QCT calculations. 相似文献
995.
Ahmad H Saito N Kagawa Y Okubo M 《Langmuir : the ACS journal of surfaces and colloids》2008,24(3):688-691
Micrometer-sized, monodisperse polystyrene (PS)/poly[methyl methacrylate-(chloromethyl)styrene] [P(MMA-CMS)] composite particles having hemispherical structure were prepared by solvent evaporation from toluene droplets containing dissolved PS and P(MMA-CMS) dispersed in aqueous solution, which had been prepared using the membrane method. The formation of hemispherical ("Janus") morphology by phase separation between the PS and the P(MMA-CMS) was confirmed by both optical and electron microscopy. Atom transfer radical polymerization (ATRP) of 2-(dimethylamino)ethyl methacrylate (DM) was subsequently carried out in the presence of hemispherical PS/P(MMA-CMS) composite particles in an aqueous dispersed system. After polymerization, the morphology of the particles changed from spherical to "mushroom" shape as observed by scanning electron microscopy, indicating that DM polymerized inside or on the surface of half [P(MMA-CMS) phase] of the particles. 1H NMR spectra were consistent with chloromethyl functional groups in P(MMA-CMS) operating as ATRP initiators in the DM polymerization. 相似文献
996.
Bulut S Gonzalez-Pérez A Olsson U 《Langmuir : the ACS journal of surfaces and colloids》2008,24(1):22-25
A novel and a simple method that allows direct imaging of viscous samples by cryo-TEM (cryo-transmission electron microscopy) is presented. A fracture on the vitrified sample is created in a controlled way. In the fracture, some edges are thin enough to allow direct imaging in transmission mode. The method was used to directly image a nonionic surfactant lamellar phase where a random mesh structure is formed at lower temperatures (<10 degrees C). A so-called random mesh phase, characterized by the presence of perforated surfactant bilayers, is imaged here for the first time. Images from the mesh structure are compared with images from the classical lamellar structure formed at room temperature. 相似文献
997.
Naser Seyed Matin Hasan A. Savadkoohi Seyed Younos Feizabadi 《Plasma Chemistry and Plasma Processing》2008,28(2):189-202
The partial oxidation of methane to C2 hydrocarbons was investigated experimentally in a dielectric-barrier discharge (DBD) reactor. The effects of reactor wall
temperature, input gas flow rate and volumetric ratio of methane to oxygen over methane conversion and C2 production were investigated. The highest C2 selectivity of about 50% was achieved at 1.8% methane conversion. Finally the model equations were used to correlate methane
conversion and ethylene selectivity with the system variable within the studied range of them. The correlation equation shows
the sole effects and interaction effects of system variables on methane conversion and ethylene selectivity. 相似文献
998.
The aquation of chromium(III)-isocinchomeronato and quinolinato complexes, mer-[Cr(icaH)3]0 and mer-[Cr(quinH)3]0 (where icaH− and quinH− are N,O-bonded isocinchomeronic and quinolinic acid anion, respectively) was studied in NaOH solutions. The process leads
to successive ligand liberation in the fully deprotonated species. The kinetics of the first ligand liberation were studied
spectrophotometrically in the visible region. A mechanism is proposed in which the rate of the chelate-ring opening at the
Cr–N bond is much faster than the rate of the Cr–O bond breaking. The rate-determining step is described by the rate law:
k
obs1 = k
OH(1) + k
O
Q
2 [OH−], where k
OH(1) and k
O are rate constants of the first ligand liberation from the hydroxo- and oxo-forms of the intermediate, respectively, and
Q
2 is an equilibrium constant between these two protolytic forms. The first pseudo-first-order rate constants (k
obs1) were calculated using SPECFIT software for an A → B → C reaction pattern. The results are compared with those determined
in acidic medium. Kinetics of the second and third ligand liberation were also studied and values of successive pseudo-first-order
rate constants (k
obs2, k
obs3) are [OH−] independent. Effect of chromium(III)-quinolinato and isocinchomeronato complexes on 3T3 fibroblast proliferation was evaluated.
Cytotoxicity of these complexes is low, suggesting they may be promising candidates as novel dietary supplements. 相似文献
999.
The chromium(III) complexes with a new potential chromium transporting ligand—2,5-pyridinedicarboxylic acid (isocinchomeronic
acid, icaH2):[Cr(icaH)3]0, [Cr(icaH)2 (H2O)2]+ and [Cr(icaH)(H2O)4]2+ (where icaH = N,O-bonded isocinchomeronic acid anion), have been obtained and characterized in solution. The [Cr(icaH)3]0 complex undergoes aquation in acidic media to the diaqua-product. Kinetics of this process was studied spectrophotometrically
in the 0.1–1.0 M HClO4 range, at I = 1.0 M. The first aquation stage, the chelate-ring opening at the Cr–N bond, is a much faster than the second one. The rate
laws are of the form: k
obs = k
1 + k
−1/Q
1[H+] and k
obs = k
2
Q
2[H+]/(1 + Q
2[H+]), where k
1 and k
2 are the rate constants for the chelate-ring opening and the ligand liberation, respectively, k
−1 is the rate constant of the chelate-ring closure, Q
1 and Q
2 are the protonation constants of the pyridine nitrogen and 5-carboxylate group in the one-end bonded intermediate, respectively.
The results are discussed in terms of potential pharmaceutical application of the complex. 相似文献
1000.
Ufuk Sancar Vural Fatih Durmaz Ozcan Kocyigit Hasan Kocyigit V. Muradoglu Beril Akin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(13):2260-2268
Excess molar volumes (V
E), viscosities, refractive index, and Gibbs energies were evaluated for binary biodiesel + benzene and toluene mixtures at
298.15 and 303.15 K. The excess molar volumes V
E were determined from density, while the excess Gibbs free energy of activation G*E was calculated from viscosity deviation Δη. The excess molar volume (V
E), viscosity deviation (Δη), and excess Gibbs energy of activation (G*E) were fitted to the Redlich-Kister polynomial equation to derive binary coefficients and estimate the standard deviations
between the experimental data and calculation results. All mixtures showed positive V
E values obviously caused by increased physical interactions between biodiesel and the organic solvents. 相似文献