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11.
F. Betül Kaynak Devrim
ztürk Süheyla
zbey Gültaze apan 《Journal of Molecular Structure》2005,740(1-3):213-221
The condensation products of 5-methyl-3-phenyl-1H-indole-2-carbohydrazide (1) with 2-butanone, 3-pentanone and cyclopentanone were prepared. The adducts (2a-c) were characterized by microanalysis, UV, IR, 1H NMR, 13C NMR and EI mass spectrometry. 1H NMR spectra of 2a and 2b revealed rotational restriction about the C–N bond in solution (DMSO-d6) and displayed double resonances associated with the CH3 and CH2CH3 residues of the alkylidene moieties. A variable temperature 1H NMR experiment was run on 2a to overcome the rotational barriers and thus determine the coalescence temperature but no coalescence was observed up to 77 °C. The structural analysis of 2a and 2c were also carried out by single crystal X-ray diffraction and confirmed by theoretical calculations (semiempirical PM3 and ab initio RHF/6-31G(d)). 相似文献
12.
Devrim Çakmak 《International Journal of Mathematical Education in Science & Technology》2013,44(7):964-970
In this note, by using elementary calculus on time scales, we recall the direct proof of the equivalence between Rolle's and generalized (Cauchy's) mean value theorems on time scales. 相似文献
13.
Atilla D Durmuş M Gürek AG Ahsen V Nyokong T 《Dalton transactions (Cambridge, England : 2003)》2007,(12):1235-1243
The synthesis, photophysical and photochemical properties of the tetra- and octa-poly(oxyethylene)substituted zinc (II) phthalocyanines are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. General trends are described for photodegradation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethylsulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The effects of the substituents on the photophysical and photochemical parameters of the zinc(II) phthalocyanines (3a, 5a and 6a) are also reported. The singlet oxygen quantum yields (Phi(Delta)), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism) ranged from 0.60 to 0.72. Thus, these complexes show potential as Type II photosensitizers. The fluorescence of the complexes was quenched by benzoquinone (BQ). 相似文献
14.
Serkan Levent Ulviye Acar Çevik Begüm Nurpelin Sağlık Özgür Devrim Can Ümide Demir Özkay 《Phosphorus, sulfur, and silicon and the related elements》2017,192(4):469-474
The present study was undertaken to synthesize some novel lipophilic piperazine and piperidinedithiocarbamates and investigate their inhibitory potencies against cholinesterase enzymes. In the synthetic studies, 44 new compounds were isolated. The structures of the synthesized compounds were confirmed by spectroscopic analyses. Enzymatic studies were carried out using modified Ellman's assay against Acetylcholinesterase (AChE) and Butrylcholinesterase (BChE) enzymes, and it was observed that some of the compounds selectively inhibit AChE. Theoretical ADME predictions were calculated for selected compounds in the series. Enzyme kinetics and molecular docking studies were performed for the most active compound C41 and nature of inhibition and interactions between enzyme and ligand were explained. 相似文献
15.
Sevdiye Atakul Savrık Devrim Balköse Sevgi Ulutan Semra Ülkü 《Journal of Thermal Analysis and Calorimetry》2010,101(2):801-806
The effect of emulsion process formulation ingredients on the morphology, structure, and properties of polyvinyl chloride
(PVC) powder has been considered in this study. PVC powder was extracted with ethanol and films were obtained by solvent casting
from tetrahydrofurane. Characterization of powders, films, and ethanol extract was performed through FTIR spectroscopy, DSC,
AFM, SEM, EDX analysis, methylene blue, and nitrogen adsorption. PVC powder was composed of spheres of a large particle size
range from 10 nm to 20 μm as shown by SEM. The specific surface area of the PVC powder was determined as 16 and 12 m2 g−1 from methylene blue adsorption at 25 °C and from N2 adsorption at −196 °C, respectively. AFM indicated the surface roughness of the films obtained by pressing the particles
was 25.9 nm. Density of PVC powder was determined by helium pycnometry as 1.39 g cm−3. FTIR spectroscopy indicated that it contained carbonyl and carboxylate groups belonging to additives such as surface active
agents, plasticizers, and antioxidants used in production of PVC. These additives were 1.6% in mass of PVC as determined by
ethanol extraction. EDX analysis showed PVC particles surfaces were coated with carbon-rich materials. The coatings had plasticizer
effect since, glass transition temperature was lower than 25 °C for PVC powder and it was 80 °C for ethanol extracted powders
as found by using differential scanning calorimetry. These additives from polymerization process made PVC powder more thermally
stable as understood from Metrom PVC thermomat tests as well. 相似文献
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17.
Sebile Işık Büyükekşi Sevinc Zehra Topal Devrim Atilla 《Journal of fluorescence》2017,27(4):1257-1266
Herein, novel silicon (IV) phthalocyanines peripherally substituted by triethylene glycol groups and bearing axial hydroxyl groups were synthesized and fully characterized by using different analyses techniques. The photophysical and photochemical properties of octa (2a) and tetra (2b) derivatives were investigated in DMF and DMSO. The effect of octa or tetra substitution on fluorescence quantum yield, singlet oxygen generation and photodegradation were examined, and the differences were evaluated regarding their potential efficiency in photodynamic therapy (PDT). Their pH-responses were investigated to determine the influence of protonation of azomethine nitrogen atoms on singlet oxygen generation efficiencies. Dramatic optical changes were observed by protonation of azomethine bridges of 2a and 2b. They exhibited signal decrease from pH 4.0 to 1.0 for 2a (pKa = 2.6) and pH 3.0 to 1.0 for 2b (pKa = 1.8). Besides, the compounds exhibited no aggregation tendency, moderate fluorescence quantum yield, solubility in common organic solvents, high singlet oxygen quantum yield and high photostability in DMF and in DMSO, these favorable properties making them good candidates as photosensitizer for PDT. 相似文献
18.
Devrim Çakmak 《Journal of Mathematical Analysis and Applications》2003,278(2):562-576
In this paper, by using the method of general means, some new oscillation criteria for forced functional differential equations of the form
19.
Nazl Turan Yücel Derya Osmaniye Ümmühan Kandemir Asaf Evrim Evren
zgür Devrim Can Ümide Demir
zkay 《Molecules (Basel, Switzerland)》2021,26(11)
In this study, we aimed to design and synthesize novel molecules carrying both the thiazole and piperazine rings in their structures and to investigate their antinociceptive activity. Targeted compounds were obtained by reacting thiosemicarbazide derivative and appropriate 2-bromoacetophenone in ethanol. The structures of the obtained compounds were determined using data from various spectroscopic methods (IR, 1H-NMR, 13C-NMR, and LCMSMS). Experimental data from in vivo tests showed that test compounds 3a–3c, 3f, and 3g (50 mg/kg) significantly prolonged reaction times of animals in tail-clip and hot-plate tests compared to the controls, indicating that these compounds possess centrally mediated antinociceptive activities. Furthermore, these compounds reduced the number of writhing behaviors in the acetic acid-induced writhing tests, showing that the compounds also possess peripheral antinociceptive activity. In the mechanistic studies, naloxone pre-treatments abolished the antinociceptive activities of compounds 3a–3c, 3f, and 3g, indicating that opioidergic mechanisms were involved in their antinociceptive effects. Molecular docking studies demonstrating significant interactions between the active compounds and µ- and δ-opioid receptor proteins supported the pharmacological findings. This study is the first showing that molecules designed to bear thiazole and piperazine moieties together on their structure exert centrally and peripherally mediated antinociceptive effects by activating the opioid system. 相似文献
20.