Browsing by Author "Ay K."
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Item The effect of simvastatin on serum cytokine levels and bone metabolism in postmenopausal subjects: Negative correlation between TNF-α, and anabolic bone parameters(Springer Japan, 2004) Tikiz C.; Ünlü Z.; Tikiz H.; Ay K.; Angin A.; Onur E.; Var A.; Tüzün Ç.In this prospective study, we aimed to evaluate the effect of simvastatin on bone metabolism and the correlation between changes in bone turnover parameters and serum cytokine levels. For this purpose, 38 postmenopausal subjects with hypercholesterolemia (>240mg/dl), not on osteoporosis treatment, were studied. Simvastatin was started at a dose of 20mg daily and continued for 3 months. Six patients were excluded from the study during the follow-up period. Pre- and post-treatment samples were analyzed for bone alkaline phosphatase (BAP) and osteocalcin (OCL), as markers of bone formation; for carboxyterminal telopeptide of collagen I (CTX), as a marker of bone resorption; and for interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) cytokine levels. Total cholesterol level was decreased from 262.1 ± 30.9 to 210.2 ± 35.6mg/dl after simvastatin treatment (P < 0.0001). While no significant change was observed in serum CTX level, BAP and OCL levels were significantly increased (from 120.8 ± 56.6 to 149.5 ± 57.6 IU/I [P = 0.008], and from 20.8 ± 12.6 to 34.7 ± 18.4 μg/l [P = 0.015], respectively). In the analysis of cytokines, while no significant change was observed in IL-6 levels, the TNF-α level was found to be significantly decreased after simvastatin treatment (from 77.9 ± 31.6 pg/ml to 23.5 ± 12.6 pg/ml [P = 0.021]). Individual changes in TNF-α levels showed a moderate negative correlation with the individual changes in BAP and OCL levels (r = -0.550 [P = 0.001], and r = -0.497 [P = 0.004], respectively). In conclusion; 20-mg daily simvastatin treatment for 3 months significantly increased BAP and OCL levels (markers of bone formation) in hypercholesterolemic postmenopausal subjects, without affecting bone resorption. These findings support the idea that simvastatin has an anabolic effect on bone formation. Additionally, the presence of a negative correlation between TNF-α levels and the anabolic bone parameters suggests that a cytokine-lowering effect of simvastatin may also be involved in the remodeling process and could exert some additive beneficial effect on bone metabolism.Item Intra-articular injection of tenoxicam in the treatment of osteoarthritis of the knee(2006) Unlu Z.; Ay K.Objectives: The aim of this study was to determine whether tenoxicam, administered by the intra-articular route, is useful for the treatment of osteoarthritis [ OA] of the knee. Methods: Patients with knee OAwere placed into three groups. Patients with no evidence of inflammation were randomized into Groups 1 and 2. Group 3 consisted of patients with knee OA with associated signs of inflammation. Groups 1 and 3 received three weekly intra-articular injections of tenoxicam, whereas only physical exercise was applied to Group 2. The Western Ontario McMaster Universities Index [WOMAC], the Lequesne Index for knee OA, and physical examination findings of the knee joint were used in the clinical and functional evaluations at baseline and months 1, 3, and 6. Results: A total of 63 subjects participated in this study. Statistically significant improvements from baseline were detected in Group 1 and Group 3, but not in Group 2. There was no lasting benefit from tenoxicam therapy since Groups 1 and 2 showed no significant differences at the six-month conclusion of the study. Similarly, Group 1 and Group 3 did not differ significantly. Conclusions: Intra-articular tenoxicam therapy seemed to show greater efficacy for pain and improvement of functional performance than exercise therapy alone, but the effects were no longer present. Tenoxicam, given intra-articularly, may provide benefit from the symptoms of OA, but the effects are transient. Copyright © by The Haworth Press, Inc. All rights reserved.Item Comparison of intra-articular tenoxicam and oral tenoxicam for pain and physical functioning in osteoarthritis of the knee(2006) Unlu Z.; Ay K.; Tuzun C.This study was designed to compare efficacy of local administration of a nonsteroidal anti-inflammatory drug with systemic administration in patients with osteoarthritis (OA) of the knee. For this purpose, intra-articular tenoxicam and oral tenoxicam therapies were applied and the improvement in control of pain and physical functioning were evaluated. A total of 69 patients with OA of the knee were randomized into three groups. Patients in the first group (41 knees of 23 patients) were treated for 1-3 weeks with once weekly intra-articular injection of tenoxicam 20 mg. Patients in the second group (45 knees of 26 patients) received 20 mg/day tenoxicam orally for 3 weeks and only physical exercises were applied to the third group (32 knees of 20 patients). Physical examination of the knee joint, Western Ontario and McMaster Universities Index and the Lequesne Algofunctional Index were used as outcome measurements at baseline, and the 1st, 3rd and 6th months. More significant improvement in pain and disability parameters was observed in groups 1 and 2 than group 3 compared with baseline measures. Among the patients' responses a few of the differences were statistically significant, more in favour of tenoxicam, and tenoxicam seemed to be superior to exercise alone especially at the final evaluation. There was no significant difference between the oral and intra-articular tenoxicam treatment regimens. The results of this study showed that treatment of OA of the knee with intra-articular tenoxicam is as effective as that with oral tenoxicam. It can be thought that intra-articular administration can be preferred to oral therapy due to minimal possibility of systemic side effects. © Clinical Rheumatology 2005.Item Efficacy of low level laser treatment in plantar calcaneal enthesophytosis(2006) Tikiz C.; Ünlü Z.; Ay K.; Tüzün Ç.The present study was conducted to assess the efficacy of low-intensity laser therapy in the treatment of plantar calcaneal enthesophytosis (PCE). Forty patients suffering from pain at least for more than one month with the diagnosis of PCE were included in the study. Patients were randomized into two groups as; active laser group (ALG, n=20, mean age 49±10 years) and placebo laser group (PLG, n=20, mean age 54±5 years). Gallium-aluminum-arsenide (GaAlAs) infrared diode device (30mW, 830 nm) was used for low-level laser treatment (LLLT). Patients were treated five times weekly for 3 weeks. Baseline evaluation consisted of the severity of resting pain, morning pain, pain after activity, pain on palpation, and the effect of pain on daily activities and walking ability. Assessments were done before treatment, at the end of treatment and at 1-month follow-up. Baseline patient characteristics were similar in both groups. In intra-group comparisons, significant improvements were detected in all outcome measurements at both post-treatment and one-month follow-up period in ALG (p<0.05), however no significant difference was observed in PLG concerning the same time intervals. Inter-group comparisons also revealed significant difference in favor of ALG except walking period without pain at 1-month follow-up period. In conclusion, we suggest that low-level laser is an effective treatment modality for PCE and it can be used as an alternative treatment method to other conventional treatment modalities.Item The Wittig-cyclization procedure: acid promoted intramolecular formation of 3-C-branched-chain 3,6-anhydro furano sugars via 2′-oxopropylene derivatives(2007) Ay K.; Çetin F.; Yüceer L.Some olefinic Wittig products, 3-deoxy-5,6-O-isopropylidene-3-C-(2′-oxopropylene)-1,2-O-alkylidene hexofuranose derivatives were converted to the branched-chain 3,6-anhydro-3-C-(2′-oxopropyl) derivatives on treatment with ion exchange resin Amberlite 120 (H+) in methanol-water at room temperature. Hydrolysis of 5,6-isopropylidene groups and intramolecular ring-closures took place in one pot reactions. © 2007 Elsevier Ltd. All rights reserved.Item Synthesis and antimicrobial activities of two novel amino sugars derived from chloraloses(2010) Yenil N.; Ay E.; Ay K.; Oskay M.; Maddaluno J.The synthesis of 5-amino-5-deoxy-1,2-O-(S)-trichloroethylidene-β-l-arabinofuranose and 6-amino-6-deoxy-1,2-O-(S)-trichloroethylidene-α-d-glucofuranose is described by a simple three- or four-step route. Antibacterial potency of the new compounds was determined using an inhibition zone diameter test. The results show that these compounds have a broad-spectrum activity against Gram-positive, Gram-negative bacteria and Candida albicans. © 2010 Elsevier Ltd. All rights reserved.Item Determination of some chemical parameters and antimicrobial activity of traditional food: Mesir paste(2010) Oskay M.; Karaildirim T.; Ay E.; Ay K.The antimicrobial activities and some chemical properties of the traditional Turkish food called mesir paste were studied. Results of chemical analysis for moisture and volatiles, water-insoluble components, refractive index, soluble solids content, raw fiber, invert sugar, total ash, 5-hydroxymethylfurfural, acidity, and pH were calculated as 17.06%, 2.55%, 1.491, 80.2%, 0.70%, 40.54%, 0.13%, 44 mg/kg, 0.9% anhydrous citric acid, and 3.6, respectively. Mesir paste was extracted individually by six solvents with different polarity, and antimicrobial activities of each extracts were determined against 12 microbial strains, mostly food-borne, including pathogens, by the agar well diffusion method. All extracts obtained showed antimicrobial activity ranging from 8 mm to 40 mm, and the butanolic extract displayed stronger antimicrobial activity against all tested microorganisms; Gram-positive strains were found to be more sensitive than Gram-negative strains. Antimicrobial potency of n-butanol extracts of mesir paste was determined in term of minimal inhibitory concentration and minimal bactericidal concentration for the sensitive microorganisms. In addition, some commercial antibiotics such as ampicillin, gentamicin, and nystatin were used as positive controls to determine the sensitivity of the strains. © 2010, Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition.Item The knoevenagel-doebner reaction on 1,2-O-(2,2,2-Trichloroethylidene) derivatives of D-Gluco- and D-Manno- furanose(2010) Kök G.; Karayildirim T.; Ay K.; Ay E.The synthesis of new α,β-unsaturated furanuronic acid derivatives of α-gluco- (3) β-gluco- (6) and β-manno-chloraloses (9) via a convenient one pot procedure using the Knoevenagel-Doebner reaction approach are described. The dialdofuranose derivatives were reacted with malonic acid under Knoevenagel-Doebner reaction conditions and (E)- α,β-unsaturated furanuronic acid derivatives were obtained. © 2010 licensee MDPI Basel Switzerland.Item The newest member of the family of chloralose: Synthesis of β -ribochloralose and some derivatives(2013) Ay K.; Halay E.Treatment of D-ribose with chloral in the presence of acid catalyst gives 1,2-O-(S)-trichloroethylidene-α-D-ribofuranose (1) (β-ribochloralose) . Some derivatives of this product (1) were synthesized to be used as an intermediate in carbohydrate chemistry. Tricyclic orthoester structure (3, 77%) was obtained from the reaction of 1 with potassium t-butoxide. This novel orthoester is expected to be useful as a glycosyl donor in the formations of new ribofuranoside units. 3-O-Methyl-ribochloralose (5) was synthesized in 75% yield via the methylation of 1. 5-O-Tosyl-ribochloralose (6, 61%) was prepared with monotosylation reaction of 1. Treatment of 6 with NaN3 in DMF gives a 5-azido-5-deoxy-ribochloralose (7) in 77% yield. The azidosugar (7) was reduced to 5-amino-5-deoxy-ribochloralose (8, 72%) with triphenylphosphine according to Staudinger's reduction procedure. © 2013 Kadir Ay and Erkan Halay.Item Acid promoted intramolecular formation of 3,5-anhydro-1,4-furano-7-ulose derivatives via the Wittig-cyclization procedure and their antimicrobial properties(2013) Telli F.C.; Ay K.; Murat G.; Kök G.; Salman Y.We report a convenient method for the synthesis of 3,5-anhydrofuranose derivatives. Formation of the 3,5-anhydro (oxetane) rings was achieved by the Wittig-cyclization procedure under acid promoted conditions starting from 5(E)-eno-1,4-furano-7-ulose derivatives (1, 4, and 7). Unprotected hydroxyl groups on C-3 of the furanose rings added intramolecularly to the acyclic double bond under very mild acidic conditions in methanol to form the stereoisomeric 3,5-anhydro derivatives in good yields. The products (2, 3, 5, 6, and 8) were found to exhibit antibacterial properties. The reaction was found to be strongly solvent dependent as use of methanol instead of chloroform afforded 5-acetylmethyl-furfural 9 as a major product instead of the expected oxetane. All of the synthesized compounds were tested for antimicrobial activity against Staphylococcus aureus ATCC6538-P, Bacillus subtilis ATCC 6633, Salmonella typhimurium CCM 5445, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 12228, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae CCM 2318, and Candida albicans ATCC 10239 and exhibited a range of activities against selected microorganisms. © 2012 Springer Science+Business Media, LLC.Item Synthesis and characterization of chloralose-derived thiosemicarbazones and semicarbazones and investigation of their antimicrobial properties(Taylor and Francis Inc., 2014) Yetgin C.E.; Oskay M.; Ay K.Thiosemicarbazones(7-10)/semicarbazones(11-14) were synthesized in good yields via the condensation of α-gluco-, β-gluco-, galacto-, manno- chloralose derived 1,4-furanodialdoses (1-4) with thiosemicarbazide(5)/ semicarbazide(6). The structures of all products were characterized by FTIR, NMR spectroscopic methods and elemental analysis. The compounds have been found to display moderate antimicrobial activity against Gram-positive, Gram-negative bacteria and antifungal activity against a Candida albicans. MIC values of the compounds range from 260 to 1510 g/mL. © 2014 Taylor & Francis Group, LLC.Item Synthesis, characterization and non-isothermal decomposition kinetic of a new galactochloralose based polymer(2014) Kök G.; Ay K.; Ay E.; Doǧan F.; Kaya I.A glycopolymer, poly(3-O-methacroyl-5,6-O-isopropylidene-1,2-O-(S)- trichloroethylidene-α-d-galactofuranose) (PMIPTEG) was synthesized from the sugar-carrying methacrylate monomer, 3-O-methacroyl-5,6-O-isopropylidene-1, 2-O-(S)-trichloroethylidene-α-d-galactofuranose (MIPTEG) via conventional free radical polymerization with AIBN in 1,4-dioxane. The structures of glycomonomer and their polymers were confirmed by UV-vis, FT-IR, 1H NMR, 13C NMR, GPC, TG/DTG-DTA, DSC, and SEM techniques. SEM images showed that PMIPTEG had a straight-chain length structure. On the other hand, the thermal decomposition kinetics of polymer were investigated by means of thermogravimetric analysis in dynamic nitrogen atmosphere at different heating rates. The apparent activation energies for thermal decomposition of the PMIPTEG were calculated using the Kissinger, Kim-Park, Tang, Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Friedman methods and were found to be 100.15, 104.40, 102.0, 102.2, 103.2 and 99.6 kJ/mol, respectively. The most likely process mechanism related to the thermal decomposition stage of PMIPTEG was determined to be a Dn deceleration type in terms of master plots results. © 2013 Elsevier Ltd. All rights reserved.Item Syntheses of 1,2,3-triazole-bridged pyranose sugars with purine and pyrimidine nucleobases and evaluation of their anticancer potential(Taylor and Francis Inc., 2017) Halay E.; Ay E.; Şalva E.; Ay K.; Karayıldırım T.With the aim to create a library of compounds with potential bioactivities by combining special characteristics of two important groups such as nucleobases and carbohydrates, twenty 1,4-disubstituted-triazole nucleosides were synthesized in good yields (80-94%) using the copper catalyzed ‘Click’ reaction between azido-modified pento- or hexopyranoses and alkyne-bearing pyrimidine or purine nucleobases. Structural elucidation was made with the assistance of spectroscopic techniques such as FTIR, 1D-, 2D-NMR, and ESI-TOFMS. All the synthesized triazole nucleosides were evaluated for their cytotoxic activity against three human cancer cell lines (MDA-MB-231, Hep3B, PC-3) by using the MTT assay. Particularly, compounds 3a and 1b were identified as potential hits against Hep3B cell. © 2017 Taylor & Francis Group, LLC.Item Synthesis and antimicrobial evaluation of sulfanilamide- and carbohydrate-derived 1,4-disubstitued-1,2,3-triazoles via click chemistry(Birkhauser Boston, 2017) Ay K.; Ispartaloğlu B.; Halay E.; Ay E.; Yaşa İ.; Karayıldırım T.4-Sulfanilamido substitued-1,2,3-triazoles conjugated with monosaccharides (8–17) including d-glucose, d-galactose, d-mannose, and d-fructose were synthesized in good yields from azidosugars with propargyl sulfanilamides using copper catalyst 1,3-dipolar cycloaddition reaction (CuAAC). The structures of new compounds were elucidated by liquid chromatography-mass spectrometry, infrared, one-dimensional- and two-dimensional-nuclear magnetic resonance techniques. All of the new compounds were tested in vitro against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhimurium, Klebsiella pneumoniae, Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans for their antibacterial and antifungal activities. Experimental results showed antimicrobial activity with minimum inhibitory concentrations values a ranging from 0.078 to 5.0 mg/mL against test microorganisms. © 2017, Springer Science+Business Media New York.Item Synthesis of triazolylmethyl-linked nucleoside analogs via combination of azidofuranoses with propargylated nucleobases and study on their cytotoxicity(Springer New York LLC, 2018) Halay E.; Ay E.; Şalva E.; Ay K.; Karayıldırım T.[Figure not available: see fulltext.] Copper(I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition reactions (CuAAC) between azidofuranoses and propargyl-nucleobases were carried out in the presence of CuSO4·5H2O and sodium ascorbate as catalytic system to provide the corresponding 1,4-disubstituted-1,2,3-triazole-bridged nucleoside analogs in good yields. Twelve new sugar-based triazolylmethyl-linked nucleoside analogs were synthesized and screened for their cytotoxic activity against MDA-MB-231, Hep3B, PC-3, SH-SY5Y, and HCT-116 cancer cell lines and control cell line (L929). Most of the compounds were moderately effective against all the cancer cell lines assayed. Particularly, among the tested compounds, 1,2,3-triazole-linked 5-fluorouracil–mannofuranose hybrid was found to be the most potent cytotoxic agent against HCT-116, Hep3B, SH-SY5Y cells with IC50 values of 35.6, 71.1, and 75.6 μM, respectively. None of the triazolylmethyl-linked nucleoside analogs exhibited cytotoxic effect against the control cells L929. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.Item Formulation, characterization, cytotoxicity and Salmonella/microsome mutagenicity (Ames) studies of a novel 5-fluorouracil derivative(Elsevier B.V., 2018) Köksal Karayildirim Ç.; Kotmakçi M.; Halay E.; Ay K.; Başpinar Y.5-Fluorouracil is one of the first line drugs for the systemic therapy of solid tumors like breast, colorectal, oesophageal, stomach, pancreatic, head and neck. It could be shown that sugars can improve the absorption across cell membranes and can help to bypass some pharmacokinetic problems. Carbohydrates as most common organic molecules are an important issue of plant and animal metabolisms. They are non toxic and have important duties in the body like participating in DNA and RNA synthesis and being responsible for energy production. In addition, they have many hydroxyl, aldehyde and ketone groups that attract attention for synthesis as a potential drug derivative. 1,2,3,-Triazole compounds have also important role in heterocyclic chemistry because of their pharmaceutical properties and their high reactivity, which could be used as a building block for complex chemical compounds. In this study, following the “Click Reaction” of 5-FU and tetra-O-acetylglycose the 5-fluorouracil derivative 1-[{1′-(2″,3″,4″,6″-tetra-O-acetyl-β-D-glycopyronosyl)-1′H-1′,2′,3′-triazole-4′-yl} methyl]5-fluorouracil was synthesized. Following, a micellar formulation of 5-Fluorouracil derivative was prepared and characterized in terms of particle size, polydispersity index, zeta potential, refractive index and pH. Furthermore, the cytotoxicity and mutagenicity of the 5-fluorouracil derivative was investigated using an in vitro cell culture model and the AMES test. According to the results of this study, the novel 5-fluorouracil derivative could be a drug candidate for the therapy of cancer and needs further in vivo investigations. © 2018 The AuthorsItem Radiolabeling and in vitro evaluation of a new 5-fluorouracil derivative with cell culture studies(John Wiley and Sons Ltd, 2019) Ilem-Ozdemir D.; Atlihan-Gundogdu E.; Ekinci M.; Halay E.; Ay K.; Karayildirim T.; Asikoglu M.The clinical impact and accessibility of 99mTc tracers for cancer diagnosis would be greatly enhanced by the availability of a new, simple, and easy labeling process and radiopharmaceuticals. 5-Fluorouracil is an antitumor drug, which has played an important role for the treatment of breast carcinoma. In the present study, a new derivative of 5-Fluorouracil was synthesized as (1-[{1′-(1′′-deoxy-2′′,3′′:4′′,5′′-di-O-isopropylidene-β-D-fructopyranose-1′′-yl)-1′H-1′,2′, 3′-triazol-4′-yl}methyl]-5-fluorouracil) (E) and radiolabeled with 99mTc. It was analyzed by radio thin layer chromatography for quality control and stability. The radiolabeled complex was subjected to in vitro cell-binding studies to determine healthy and cancer cell affinity using HaCaT and MCF-7 cells, respectively. In addition, in vitro cytotoxicity studies of compound E were performed with HaCaT and MCF-5 cells. The radiochemical purity of the [99mTc]TcE was found to be higher than 90% at room temperature up to 6 hours. The radiolabeled complex showed higher specific binding to MCF-7 cells than HaCaT cells. IC50 values of E were found 31.5 ± 3.4 μM and 20.7 ± 2.77 μM for MCF-7 and HaCaT cells, respectively. The results demonstrated the potential of a new radiolabeled E with 99mTc has selective for breast cancer cells. © 2019 John Wiley & Sons, Ltd.Item Structural, optical, luminescence properties and energy transfer mechanism of Tb3+/Eu3+co-doped SrLa2(MoO4)4 phosphors produced by sol-gel process(Elsevier Ltd, 2019) Keskin İ.Ç.; Gültekin S.; Katı M.İ.; Türemiş M.; Ay K.; Arslanlar Y.; Çetin A.; Kibar R.Tb3+/Eu3+co-doped SrLa2(MoO4)4 have been synthesized using the sol-gel process. The as-produced light-emitting phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA)/thermogravimetric analysis (TG), optical absorption spectra, radioluminescence (RL), and photoluminescence (PL) spectra. The effect of Tb3+and Eu3+doping concentrations on the RL and PL intensity of host material was analyzed in details. Furthermore, the energy transfer mechanism based on RL spectra were determined of Tb3+/Eu3+ co-doped SrLa2(MoO4)4 phosphors. When the samples excited by X-ray, the SrLa2(MoO4)4 phosphors exhibit characteristic emissions of Tb3+ (489, 544, 586, 620 and 675 nm) and Eu3+ (545, 592, 614, 650 and 700 nm). Also, similar emissions are observed in the results of PL spectra, when the samples excited by 488 nm. The host material has excellent energy transfer efficiency for lanthanide ions. In addition, the luminescence spectra indicated that the energy transfer is also effective between from Tb3+ to Eu3+ and vice versa. The CIE parameters are calculated to characterize the color emission. Under UV excitation, the synthesized materials display different color from green to red. Based on the results, the SrLa2(MoO4)4:Eu3+,Tb3+ phosphors may be potential candidates for light-emitting diode. © 2019 Elsevier B.V.Item Comprehensive study on structural, thermal, morphological and luminescence (RL, PL, TL) properties of CaLa2(WO4)4: Tb3+, Dy3+ phosphors synthesized via sol-gel method(Elsevier Ltd, 2021) Türemiş M.; Keskin İ.Ç.; Katı M.İ.; Çetin A.; Ay K.; Kibar R.Tb3+/Dy3+ co-doped CaLa2(WO4)4 (CLW: Tb3+/Dy3+) and its derivatives were synthesized by the sol-gel method. The morphology, thermal, structure and luminescent-optical properties the as-prepared light-emitting phosphors were characterized by utilizing scanning electron microscopy (SEM), differential thermal analysis (DTA)-thermogravimetric analysis (TG), X-ray diffraction (XRD) and radioluminescence (RL or X-ray luminescence) - photoluminescence (PL) –thermoluminescence (TL or TSL) - optical absorption spectrometry. The Tb3+ and Dy3+ ions were singly or doubly doped and the results were examined in detail. Moreover, for these phosphors, the energy transfer mechanisms which depend on RL and PL spectra were determined. The samples excited by X-ray demonstrate characteristic luminescence peaks of Dy3+ (422, 480, 575, 663 and 747 nm) and Tb3+ (489, 544, 586, 620, 652 and 675 nm). These emissions are similar for RL and PL measurements. It could be said that the energy transfer efficiency of the host material is perfect for rare-earth ions. The synthesized phosphors exhibit various colors from yellow to blue under UV excitation. The optical band gaps of host CLW, CLW: Tb3+, CLW: Dy3+ and co-doped CLW: Tb3+/Dy3+ were calculated at values 3.83 eV, 3.44 eV, 3.64 eV and 3.52 eV, respectively. From the results obtained, the CaLa2(WO4)4: Tb3+, Dy3+phosphors may be one of the potential candidates for light-emitting diode. © 2021 Elsevier Ltd and Techna Group S.r.l.Item Synthesis of 5-fluorouracil dimer containing 2-amino-thiazole group via click reaction; [2-amino-tiyazol grubu içeren 5-florourasil dimerinin klik tepkimesi yoluyla sentezi](TUBITAK, 2021) Öztürkoğlu G.; Ay E.; Alp H.; Ay K.Since cancer is one of the leading diseases that cause human deaths in the world, the synthesis of anticancer or new compounds with fewer side effects is important. 5-Fluorouracil (5-FU) is one of the oldest compounds used for chemotherapy. In this study, 1,2,3-triazole bridge containing compound 4, which could have potential anticancer properties, was synthesized via the click reaction from the 5-FU and 2-aminothiazole using the molecular hybridization approach. The structural elucidation of the new compound was carried out using modern spectroscopic methods such as FTIR,1H,13C,19F, COSY, HSQC, HMBC and TOF-MS. © 2021, TUBITAK. All rights reserved.