33 research outputs found
Synthesis of new trisubstituted hexahydro-isoindole-1,3-dione derivatives regio- and stereoselectivity: spectroscopic and theoretical studies
2-Hydroxy-5-alkylhexahydro-4H-oxireno[2,3-e]isoindole-4,6(5H)-diones were synthesized, and their C-2 selective ring opening products were obtained through nucleophilic additions such as with MeOH. The methoxydiols obtained from the ring-opening reactions were converted to corresponding acetate derivatives. The structures of the methoxydiacetates were determined by H-1 and C-13 NMR and X-ray analyses. Furthermore, theoretical computations were carried out to explain the regioselectivity in the ring-opening reaction of epoxy alcohols. The theoretical calculations showed that the ring-opening reaction of epoxy alcohols proceeds in a thermodynamically controlled manner and regioselectivity occurs depending on the stability of the intermediate.[GRAPHICS
Molecular Docking Studies and ADME Predictions on Synthesized Chalcone Compounds Targeting EGFR
In the present study, new chalcone derivatives (5a–5f) obtained from the condensation reaction of cuminaldehyde and acetophenone compounds containing different substituents were reported. Chemical characterization (1HNMR and 13CNMR analysis) and molecular docking studies of the synthesized compounds were performed against the epidermal growth factor receptor (EGFR) and reference drug (metachalcone). Erlotinib was used as the reference ligand. Compound 5 (-7.6 kcal mol-1), compound 6 (-7.38 kcal mol-1), and compound 7 (-7.44 kcal mol-1) were found to be the strongest inhibitors of EGFR when compared to Erlotinib (-7.0 kcal mol-1). In addition, an ADME estimation was made. It was determined that the synthesized compounds could be potent EGFR inhibitors compared to Erlotinib. Compounds 5-7 and the target protein showed a better binding affinity for EGFR than the reference compound (Erlotinib). The synthesized compounds can be potent inhibitors for EGFR-mutated cancers
Regio- and stereo-chemical ring-opening reactions of the 2,3-epoxy alcohol derivative with nucleophiles: Explanation of the structures and C-2 selectivity supported by theoretical computations
The ring-opening reactions of (1aS,2S,6bR)-5-ethyl-2-hydroxyhexahydro-4H-oxireno[2,3-e]isoindole-4,6(5H)-dione were investigated under very mild and nonchelated conditions. C-2 selective ring-opening products were obtained with nucleophilic additions such as Cl-, Br- and N-3(-). The exact configuration of (3aS,4R,5R,6S,7aS)-5-chloro-2-ethyl-4,6-dihydroxyhexahydro-1H-isoindole-1,3(2H)-dione was determined by X-Ray diffraction analysis which was obtained from the reaction of epoxy alcohol with HCl . On the other hand, theoretical computations were carried out to explain the regioselectivity in the ring opening reaction of epoxy alcohols. The results showed that the ring-opening reaction of both epoxy alcohols proceeds in a kinetically controlled manner and regioselectivity occurs depending on the transition state. (c) 2022 Published by Elsevier B.V
A RESEARCH ON WALL ENCAUSTIC TILES OF YENİ CAMİ (THE NEW MOSQUE) IN İSTANBUL
İstanbul ilinde bulunan Yeni Camii Duvar Çinileri Üzerine Bir Araştırma
konulu çalışma. Araştırma beş bölümden oluşmaktadır. Birinci bölümde; kavramsal
çerçeve üzerinde durulmuştur. Bu bölümde özellikle İstanbul' un tarihsel, kültürel
gelişimi, dini yapıları, külliyeler ve camiler, türbeler, çiniler, Yeni cami ve çinileri
hakkında geniş bilgilere yer verilmiştir. Araştırma örneklem olarak ele alınan
mihrap, kapı-pencere alınlıkları ve duvar çinilerinden oluşan 20 adet örnekle ile
sınırlandırılmıştır.
İkinci bölümde; İlgili araştırmalar başlığı altında literatür özetleri yer
almaktadır.
Üçüncü bölümde Yeni cami' de bulunan sıraltı tekniği ile yapılmış bitkisel,
yazılı, ve nesneli bezemelerle stilize hayvan motiflerinin görüldüğü mihrap, kapıpencere
alınlıkları ve duvar çinileri incelenmiştir. Bu aşamada belirlenen çiniler,
motif, kompozisyon özellikleri, ölçüm, çizim ve fotoğraflama yolu ile belgelenerek
oluşturulan inceleme formlarına işlenmiştir.
Dördüncü bölümde inceleme formlarından edinilen veriler; renk, konu ve
boyut tabloları oluşturularak değerlendirmeye alınmıştır.
Beşinci ve son bölümde; Sonuç ve önerilere yer verilmiştir.he study on the subject called A Research on Wall Encaustic Tiles of Yeni
cami (the New Mosque) in İstanbul. The study consists of five chapters. The first
chapter deals with the conceptual framework. In this chapter, there are information
about the historical, cultural development, religious buildings, social complexes and
mosques, tombs, encaustic tiles, Yeni Cami (the New Mosque) and its encaustic
tiles. The sample in the research has been limited with 20 items consisting of
mihrab, door-window frontals and wall encaustic tiles.
The second chapter deals with the literature abstracts under the heading of
Relevant Researches.
The third chapter examines the mihrab, door-window frontals and wall
encaustic tiles where decorations with vegetable, inscription and objects made by
the under glaze technique in the Yeni Cami. The encaustic tiles determined at this
stage are entered in the examination forms by being documented through motive,
composition properties, measurement, drawing and photos.
In the fourth chapter, the data obtained from the examination forms has been
evaluated by creating colour, subject and dimension tables.
The fifth and the last chapter includes the conclusion and proposals
Bazı metakrilat ve akrilat homopolimerlerinin, kopolimerlerin ve fiberlerinin direkt piroliz kütle spektrometresi ile karakterizasyonu.
Poly(methyl methacrylate) possesses many desirable properties and is used in various areas. However, the relatively low glass transition temperature limits its applications in textile and optical-electronic industries. Monomers containing isobornyl, benzyl and butyl groups as the side chain are chosen to copolymerize with MMA to increase Tg and to obtain fibers with PMMA. In this work, thermal degradation characteristics, degradation products and mechanisms of methacrylate homopolymers, poly(methyl methacrylate), poly(butyl methacrylate), poly(isobornyl methacrylate) and poly(benzyl methacrylate), acrylate homopolymers, poly(n-butyl acrylate), poly(t-butyl acrylate), poly(isobornyl acrylate), two, three and four component copolymers of MMA and fibers are analyzed via direct pyrolysis mass spectrometry. The effects of substituents on the main and side chains, the components present in the copolymers and fiber formation on thermal stability, degradation characteristics and degradation mechanisms are investigated. According to the results obtained, the depolymerization mechanism yielding mainly the monomer is the main thermal decomposition route for the methacrylate polymers, acrylate polymers degradation occurs by H-transfer reactions from the main chain to the carbonyl groups. However, when the alkoxy group involves -H, then, H-transfer reactions from the alkoxy group to the CO group also takes place leading to a complex thermal degradation mechanism. The thermal degradation mechanisms and the relative yields of products are affected by copolymerization due to the inter and intra-molecular interactions. As a consequence of transesterification reactions new fragments can be generated. In general, the samples taken from different parts of the fibers do not show different thermal degradation behavior. However, upon fiber formation, enhancements in intermolecular interactions decreasing the thermal stability and changing the product distribution are detected.Ph.D. - Doctoral Progra
GAF-MTN soğan gen havuzunda yer alan hatlarda tuz stresi uygulamasının tohum üretimine etkisi
Abiyotik stres faktörlerinin önemi, küresel ısınma nedeniyle son yıllarda görülen düzensiz iklim verileriyle artmıştır. Bu faktörlerden, soğan (Allium cepa L.) yetiştiriciliği için en önemli olanlarından birisi de toprak tuzluluğudur. Soğan, yetiştiriciliği yapılan bitkiler arasında toprak tuzluluğuna en duyarlı olanlardan birisidir. Ayrıca, büyüme döneminin belirli aşamalarında, su ihtiyacının karşılanması çok önemli olan bir bitkidir. Bu çalışmada, tuzluluğun soğan tohumu üretimine etkisi vurgulanmıştır. GAF-MTN gen havuzunda aday çeşit olan 10 kısa gün soğan hattı ve 15 uzun gün soğan hattı kullanılmıştır. İlk olarak, baş bağlama dönemlerinde tuz stresinin uygulandığı bitkilerden elde edilen soğan başları dikilmiştir. Daha önce tuz stresine maruz kalan bu bitkiler tohum üretimi sırasında gözlenmiştir. Son olarak, tohum verimleri her bir genotip için kontrol ve stres koşulları altında değerlendirilmiştir. Çalışmanın sonunda kısa gün genotiplerine baktığımızda K18 tohum verimi bakımından tuz stresine daha toleranslı görünüyorken K52 (ticari çeşit) genotipi daha az tolerant bir genotip olarak gözlemlenmiştir. Ayrıca, uzun gün genotiplerinden olan U57 genotipi (ticari çeşit) tohum verimi açısından tuz stresine karşı daha az tolerans gösterirken U31 diğer genotiplere göre tuz stresine karşı daha toleranslı bulunmuştur. Anahtar Sözcükler: Abiyotik stres, Allium cepa L., tuz stresi, tohum verimiThe importance of abiotic stress factors has increased with the changes in climate observed in recent years due to global warming. Of these factors, one of the most important ones for onion (Allium cepa L.) cultivation is soil salinity. Onion is one of the most susceptible to soil salinity among cultivated plants. Besides, at certain stages of the growing period, the need for water which can be prevented by the presence of high salt concentration in the root is very critical for the plant. In this study, the effects of salinity on onion seed production were emphasized. 10 short-day onion lines and 15 long-day onion lines which are candidate varieties in GAF-MTN gene pool were used as plant materials. First, onion bulbs obtained from plants where salt stress was previously applied during bulbing period were planted. These bulbs were grown for onion seed production. Finally, seed yields for each genotype were evaluated under control and stress conditions. When we look at the short-day genotypes at the end of the study, K18 seems to be more tolerant to salt stress in terms of seed yield, while the K52, which is commercial variety, was seen as a less tolerant. In addition, in long-day genotypes, U57, which is another commercial variety, showed less tolerance to salt stress in terms of seed yield, while U31 was more tolerant to salt stress than other genotypes. Keywords: Abiotic stress, Allium cepa L., salt stress, seed yiel
The effect of dispositional optimism on posttraumatic growth: Testing the moderator role of ways of coping between dispositional optimism and posttraumatic growth in Turkish breast cancer patients
The aim of the present study was to examine if coping strategies mediate dispositional optimism–posttraumatic growth relation in postoperative breast cancer patients. The data were collected from 90 patients in two hospitals. Regression analyses revealed that problem-focused coping fully mediated dispositional optimism–posttraumatic growth relation, but emotion-focused coping did not. That is, postoperative breast cancer patients who were optimistic were more likely to use problem-focused coping strategies that, in turn, led to the development of posttraumatic growth. The findings were congruent with the literature in which problem-focused coping was mostly highlighted as compared to emotion-focused coping, and in which optimism and problem-focused coping relationship was emphasized in the path of posttraumatic growth
Development and validation of stability-indicating HPLC method for diflucortolone valerate and isoconazole nitrate combination
The combination of diflucortolone valerate (DIF) and isoconazole nitrate (ISO) is commonly used in pharmaceutical preparations. Though, there are already few methods in the literature for the simultaneous determination of these two compounds, none of them involves the stability indicating property that is emphasized by the ICH guidelines. In the present study, a stability-indicating HPLC assay method was developed and subsequently validated for the simultaneous determination of diflucortolone valerate (DIF) and isoconazole nitrate (ISO) in their combined pharmaceutical cream formulations. Separation of active substances and their degradation products was achieved on an ACE column (150x4.6 mm id, 5µm particle size) with an isocratic mobile phase of sodium dihydrogen phosphate buffer and methanol mixture in the ratio of 27: 73, v/v with UV detection at 240 nm. The chromatographic separation was performed in a very short run time with a flow rate of 1.5 mL/min. The developed method was validated as per United States Pharmacopeia (USP) and International Conference on Harmonization (ICH) guidelines. DIF and ISO active substances were exposed to stress conditions separately and also in their combined drug product form in order to examine the stability indicating property of the proposed method. Stressed samples were analyzed by using HPLC equipped with a photo diode array (PDA) detector and the method was found to be stability-indicating. Therefore, we introduced a facile method for routine analysis of DIF and ISO in combined cream pharmaceutical dosage forms and their corresponding stability studies
Quantitative phase imaging of erythrocyte in epilepsy patients
The present study focuses on the quantitative phase imaging of erythrocytes with the aim to compare the morphological differences between epilepsy patients under antiepileptic treatment, who have no other disease which may affect the erythrocyte morphology, and the healthy control group. The white light diffraction phase microscopy (WDPM) has been used to obtain the interferogram of the erythrocyte surfaces. The continuous wavelet transform with Paul wavelet has been chosen to calculate the surface profiles from this interferogram image. For the determination of alteration in morphology, besides WDPM, erythrocyte surfaces have been investigated by light microscope and scanning electron microscope. In this way, it has been possible to see the difference in terms of precision and implementation between the most commonly used methods with regard to the quantitative phase imaging. Erythrocytes from all the samples have been examined and displayed in both two- and three-dimensional way. We have observed that erythrocytes of patients with effective antiepileptic blood levels were more affected in morphology than healthy subjects. When we compared the erythrocyte morphological changes of patients who received monotherapy or polytherapy, no difference was observed. In conclusion, antiepileptic drugs (AEDs) cause red blood cell (RBC) morphological changes and a combined usage of WDPM with Paul wavelet and light microscopy methods are very convenient for studying the erythrocyte morphologies on multiple patients. © 2020 Wiley Periodicals LLC19.230; 115F168This work was supported by Tekirdağ Namık Kemal University Scientific Research Project Commission (NKUBAP.02.GA.19.230) and Turkish Scientific and Technical Research Council grant (115F168)