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    Conformational, IR, NMR, and EPR analysis of ifosfamide by density functional theory calculation
    (Springer Wien, 2017) Osmanoglu, Yunus Emre; Tokatli, Ahmet; Sutcu, Kerem; Osmanoglu, Semsettin; Ucun, Fatih
    The optimized molecular structure, vibrational frequencies, H-1 and C-13 NMR chemical shifts, and EPR hyperfine splittings of 3-(2-chloroethyl)-2-[(2-chloroethyl) amino] tetrahydro-2H-1,3,2-oxazaphosphorine-2-oxide (ifosfamide) have been investigated using density functional theory (B3LYP) method with 6-31+G(d, p) basis set for the first time. The calculated optimized geometric parameters (bond lengths and bond angles), vibrational frequencies, NMR chemical shifts, and EPR hyperfine splittings were seen to be in a well agreement with the corresponding experimental data. The experimentalEPRspectrumof themoleculewas recorded after c-irradiation. From the comparison of the calculated and experimental results the formed radical was attributed to a carbon atom-centered radical occurred upon the loss of a chlorine atom due to breakage of the weak C-Cl bonds. So we mentioned that the free electron is transferred to a carbon atom through intramolecular rearrangement while the molecular charge changes to neutral situation, giving NHC alpha H2C beta H2 radical.
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    The effect of gamma radiation on some succinic acid derivatives in the solid state
    (Elsevier Science Bv, 2017) Sutcu, Kerem; Osmanoglu, Y. Emre
    2,2-dimethyl succinic acid, 2,3-dimethyl succinic acid and monomethyl succinate were exposed to gamma radiation in the form of powder. EPR measurements were carried out to investigate the free radicals produced in all of them, following irradiation. Three of the radical species formed after irradiation were identified and spectroscopic parameters were discussed thereafter. The radical species were attributed to the (C) over dotHCH(2), HOOCCH(CH3)(2)(C) over dotCOOH and H3COOCCH2(C) over dotHCOOH radicals, respectively. The hyperfine splitting constants for all radicals were confirmed by the simulation of the experimental spectra. The radiation sensitivity of the samples was mainly attributed to the EPR line properties of stable radicals. (C) 2016 Elsevier B.V. All rights reserved.
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    Electron spin resonance identification of gamma irradiated 2,4?-dichlorodiphenyl dichloroethane and 6-mercaptopurine monohydrate in the solid state
    (Elsevier Science Bv, 2018) Sutcu, Kerem; Osmanoglu, Y. Emre
    The purpose of this study is to investigate the effects of ionizing radiation on two anticancer drugs, 2,4'-dichlorodiphenyl dichloroethane (DCP) and 6-mercaptopurine monohydrate (MPM), by using electron spin resonance (ESR) spectroscopy. For that purpose the intensity of ESR signals of the samples as a function of the microwave power was investigated in the range of 0.01-100 mW at room temperature. While unirradiated samples presented no ESR signal, irradiated samples exhibited significant ESR spectra. ESR measurements were performed at low and high temperatures to study the dosimetric features of free radicals induced by gamma irradiation. In order to obtain the dose-response curves, samples irradiated with gamma at 1, 5, 10, 15, 20, and 25 kGy dose values were used. Furthermore, the g values of the radicals and the hyperfine coupling constants were also determined. Additionally, the time dependency of the samples was analyzed to study the stability of the radicals. (C) 2018 Elsevier B.V. All rights reserved.
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    EPR investigation of damage centers formed in some drug powders irradiated with gamma rays
    (Elsevier Science Bv, 2018) Sutcu, Kerem
    The radiation damage centers in levetiracetam, progesterone, ethosuximide, and propranolol hydrochloride were investigated by EPR spectroscopy at 295 K. The paramagnetic species were attributed to the -CHCHNH-, -CH2CH2CH- and -CH-, -CHCH2N- and -CH-, and -NCCH2- radicals, respectively. The results were observed as being in good conformity with the literature. The spectra of these compounds were computer simulated. Furthermore, the EPR parameters of the radicals formed by (SIC)-irradiation in the samples were determined. (C) 2018 Elsevier B.V. All rights reserved.
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    EPR investigation of gamma-irradiated L-citrulline, ?-methyl-DL-serine, 3-fluoro-DL-valine and N-acetyl-L-cysteine
    (Elsevier, 2017) Osmanoglu, Y. Emre; Sutcu, Kerem; Baskan, M. Halim
    The spectroscopic parameters of the paramagnetic species produced in gamma-irradiated L-citrulline, alpha-methyl-m-serine, 3-fluoro-DL-valine and N-acetyl-L-cysteine were investigated at room temperature at a dose of 20 kGy by using EPR technique. The paramagnetic species were attributed to NH2CONH(CH2)(3)CNH2COOH, HOCH2CCH3COOH and HOCHCCH3NH2COOH, CH3CH3CCHNH2COOH and SHCH(2)GNHCOCH(3)COOH radicals, respectively. EPR data of the unpaired electron with the environmental protons and N-14 nucleus were used to characterize the contributing radicals produced in gamma irradiated compounds. In this paper, the stability of these compounds at room temperature after irradiation was also studied. (C) 2016 Elsevier B.V. All rights reserved.
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    EPR Investigation of Gamma-Irradiated Tiopronin
    (Springer Wien, 2024) Sutcu, Kerem; Osmanoglu, Yunus Emre
    This research delves into the radiation sensitivities of tiopronin when exposed to gamma irradiation within the 2-20 kGy dose range. This particular drug sample is commonly employed in the treatment of severe homozygous cystinuria. The paramagnetic species detected within tiopronin were ascribed to the presence of the -HNCHCOOH- radical. The g factor and hyperfine constants for H atoms were computed as follows: a alpha = 1.60 mT, a beta = 1.11 mT, aN = 0.87 mT, and g = 2.0225 +/- 0.0005. In the spectra recorded across different microwave power ranges, it was found that all signals exhibited the most favorable correlations with polynomial and logarithmic functions. It was established that the experimental data within the spectra recorded across the 2-20 kGy dose range exhibited a high degree of compatibility with power and polynomial functions. Obtaining EPR signals in the spectra recorded at high temperatures and after approximately 3 months showed that stable radicals were formed in the structure as a result of irradiation.
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    EPR studies of the free radicals generated in gamma irradiated amino acid derivatives
    (Elsevier Science Bv, 2017) Osmanoglu, Y. Emre; Sutcu, Kerem
    Gamma irradiated powder forms of N-acetyl-DL-aspartic acid, N-carbamoyl-DL-aspartic acid and N-methyl-L-serine were investigated by electron paramagnetic resonance spectroscopy (EPR) at room temperature. In these compounds, the paramagnetic centers formed after irradiation were attributed to the HOOCCH2(C)over dotHCOOH, COOH(C)over dotHCHNH and HOCH2(C)over dotHCOOH radicals, respectively. The g values and the hyperfine coupling constants for the radical species are with values of g = 2.0038 +/- 0.0005, a(alpha) = 2.15 mT, a(beta)((1)) = 3.84 mT and a(beta)((2)) = 2.15 for the first radical, g = 2.0039 +/- 0.0005, a(alpha) = 1.7 mT, a(beta)((1)) = 0.62 mT, a(beta)((2)) = 0.54 mT, a(gamma) = 0.53 mT for the second radical and g = 2.0039 +/- 0.0005, a(beta)((1)) = 2.40 mT, a(beta)((2)) = 1.83 mT and a(alpha) = 1.83 mT for the third radical. The free radicals formed in three compounds were found to be stable for three months at room temperature. It was concluded that, spin density was concentrated predominantly in the 2p(pi) orbital of the carbon atom. (C) 2017 Elsevier B.V. All rights reserved.
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    Examination of the Relationship between Classroom Teachers' Multiple Intelligence Areas and Their Students' Academic Achievements
    (Kamla-Raj Enterprises, 2015) Sutcu, Nese Dokumaci; Sutcu, Kerem; Bulut, Ilhami
    The purpose of this research is to determine the relationship between multiple intelligence areas of 4th and 5th grade teachers and the grade point averages of their students in Turkish, mathematics, science and technology and social studies courses. The research sample consists of 81 classroom teachers who worked in primary schools in the central districts of Diyarbakir during the 2011-2012 academic year. In this research, single and relational survey models were used. In the analysis of the data obtained from this study, Descriptive Statistics, Independent Sample t-test and Pearson Product Moment Correlation Coefficient were used. The findings of the study, suggest that there was no statistically significant difference between the classroom teachers' average scores of verbal-linguistic, visual-spatial, naturalistic, musical, logical-mathematical, intrapersonal, interpersonal and bodily-kinesthetic intelligence areas in terms of the gender and grade level variables.
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    Radiation effect studies on some glycine derivatives in solid state
    (Taylor & Francis Ltd, 2017) Osmanoglu, Y. Emre; Sutcu, Kerem; Osmanoglu, Semsettin
    Five glycyl derivatives, glycyl-L-histidine, L-alanyl-glycine, glycine hydrochloride, gly-gly hydrochloride and, gly-gly-glycine in powder form were exposed to 20kGy doses of Co-60 gamma radiation to study the effects of ionizing radiation. In these compounds, the paramagnetic centers formed after irradiation were attributed to the RNHCHCO-OH, CH2CHNH, H2NCH2CO-OHHCl, NH2CHCONHCH2COOHHCl and HNCH2CO-OH radicals, respectively. The effect of gamma irradiation to the radical structures and time stability of the radicals were investigated by EPR spectroscopy. The spectra were computer simulated and the hyperfine coupling constants were determined.
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    Study of Dose-Response and Radical Decay Curves of Gamma Irradiated Norfloxacin Using EPR Spectroscopy
    (Amer Inst Physics, 2017) Sutcu, Kerem; Osmanoglu, Yunus Emre
    this study, Electron Paramagnetic Resonance (EPR) spectra of unirradiated and gamma-irradiated at doses of 1, 5, 10, 12 and 15 kGy norlioxacin (NOF) were investigated. Before irradiation no EPR signal were observed. After irradiation a weak singlet signal at g = 2.0039 were obtained at room temperature. In order to describe the variation of EPR signal intensity with absorbed radiation dose, several mathematical equations were tried. Increasing irradiation dose up to 15 kGy has increased the signal intensity of the central signal however, no significant changes were observed in g spectroscopic splitting factor. The stability of signal intensity of irradiated NOF was studied over a storage period of 200 days. According to analyses conducted, EPR spectroscopy can be used to distinguish irradiated and unirradiated samples from each other.