3,4-Dihidropirimidin-2-On bileşiklerinin hetorejen asit katalizörleriyle sentezi ve karekterizasyonu

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Anahtar Kelimeler: 3,4-Dihidropirimidin-2-on, Biginelli kondenzasyonu, Zirkonyum fosfat, Alumina sülfürik asit, Katı asit katalizörü, Çözücüsüz ortam reaksiyonları.Dihidroprimidinonlar ve türevleri ve farmakolojik özelliklerinden ötürü oldukca fazla ilgi çekmektedirler. Bu bileşikler anti bakteriyel, antiviral, antitümör, anti-enflamatuar aktiviteler gösterirler. Bunlardan bazıları kalsiyum kanal blokörü, antihipertansif ajan, ?1a?antagonisti ve nöropeptid Y antagonisti olarak kullanılırlar. Bazı deniz canlılarından izole edilen Batzelladin A ve B'nin yapısında dihidroprimidin iskeletinin yer aldığı bulunmuştur, bu alkaloidlerin, HIV gp-120 proteinin CD4 hücrelerine bağlanmasını inhibe eden düşük moleküler ağırlıklı ilk doğal ürünler oldukları rapor edilmiştir. 3,4-dihidropirimidin-2(1H)-on bileşiklerinin sentezi ilk kez 1983'de Biginelli tarafından etil asetoasetat, benzaldehit ve ürenin tek kapta kondensasyonu ile kuvvetli asidik şartlarda gerçekleştirilmiştir. Ancak bu yöntem özellikle substitue aromatik ya da alifatik aldehitlerle uygulandığında, sıklıkla düşük verim sağlamaktadır. Biginelli reaksiyonunun, ürünlerinin öneminden ötürü, yeni katalizörler kullanarak daha iyi ve ılıman şartlarda gerçekleştirilmesini sağlayacak çalışmalar ilgi çekmeye devam etmektedir.Bu çalışmada, iki ayrı heterojen asit katalizörü çözücüsüz ortamlarda kullanılmıştır, birincisi zirkonyum fosfat ikincisi ise alümina sülfürik asit katalizörüdür. Çeşitli 3,4-dihidroprimidinlerin sentezi zirkonyum fosfat ile 90 Santigrat derecede gerçekleştirilerek yüksek verim elde edilmiştir ve katalizör kolayca geri kazanılarak tekrar kullanıldığında aktivitesinin azalmadığı görülmüştür. Aynı reaksiyonlar alümina sülfürik asit katalizörü ile oda sıcaklığında gerçekleştirilmiş ve katalizörün yüksek aktivitesi gözlenmiştir. Her iki katalizör ile de çözücüsüz ortamda yüksek verim elde edilmiştir. Elde edilen ürünlerin 1H-NMR, 13C-NMR ve Kütle spektrumları alınarak yapıları doğrulanmıştır.Key words: 3,4-Dihydropyrimidin-2-ones, Biginelli condensation, Zirconium phosphate, Alumina sulfuric acid, Solid acid catalyst, Solvent-free reactions.Dihydropyrimidinones and their derivates have attracted considerable interest because of their pharmaceutical and therapeutic properties, such as antibacterial, antiviral, anti-tumor, anti-inflammatory activities. Some of them have been successfully used as calcium channel blockers, antihypertensive agents, ?1a-antagonists and neuropeptide Y antagonists. Additionally, their particular structure has been found in Batzelladine A and B which are the first low molecular weight natural products reported in the literature to inhibit the binding of HIV gp-120 to CD4 cells. The original procedure was reported by Biginelli in 1983, often provides low yields of the products, when substituted aromatic or aliphatic aldehyes are employed. Due to the importance of Biginelli reaction products, the discovery and introduction of better and milder conditions using new catalysts has been under attention.In this study, two different heterogeneous acid catalysts are used in solvent free conditions, the first catalyst is zirconium phosphate, and the second is alumina sulfuric acid. The synthesis of various 3,4-dihydropyrimidinines at 90 Celcius in the presence of zirconium phosphate were performed in good yields. And the catalyst was recovered easily and reused without loss of its activity. The same reactions were also carried out at room temperature by using alumina sulfuric acid as a catalyst and the catalyst exhibited remarkable reactivity. These methods not only afforded the products in high yield but also avoided the problems associated with catalyst cost, handling, safety and pollution. 1H-NMR, 13C-NMR and Mass spectrum of all the final products were elucidated

Düzenlenmiş İki Faktörlü Çalışma Süreci Ölçeği’nin (R-SPQ-2F) Türkçeye Uyarlanması

The purpose of this study is to determine the validity and reliability of the Revised Two Factor Study Process Questionnaire developed by Biggs, Kember and Leung (2001) so that it fits well into the case of Turkey. The revised version of the questionnaire was administered to 528 university students to determine its validity and reliability. The instrument consists of two main dimensions those deep learning and surface learning. Each of the main dimensions consists of two sub-dimensions. The sub-dimensions of deep learning are deep motive and deep strategy; the sub-dimensions of surface learning are surface motive and surface strategy. The instrument consists of 20 items. The factor structure of the questionnaire was investigated by descriptive and confirmatory factor analysis. The findings of the analysis showed that the latent structure of the questionnaire is best described by two factor structure model. Reliability analysis of the instrument revealed Cronbach-Alpha coefficients of 0.78 for the dimension of deep learning, 0.74 for the dimension of surface learning. These results showed that the Revised Two Factor Study Process Questionnaire can be used in Turkey.Bu çalışmanın amacı, orijinali Biggs, Kember ve Leung (2001) tarafından geliştirilen “Çalışma Süreci Ölçeği’nin düzenlenmiş formunun Türkiye koşullarında geçerlik ve güvenirlik çalışmasını yapmaktır. Geçerlik ve güvenirliğinin saptanması amacıyla ölçek 528 üniversite öğrencisine uygulanmıştır. Ölçek iki ana boyuttan oluşmakta olup her bir boyut da ikişer alt boyut içermektedir. Birinci boyut, Derin Öğrenme boyutu olup Derin Güdü ve Derin Strateji alt boyutlarından oluşmaktadır. İkinci boyut, Yüzeysel Öğrenme boyutu olup Yüzeysel Güdü ve Yüzeysel Strateji alt boyutlarından oluşmaktadır. Ölçek 20 madde içermektedir. Ölçeğin yapı geçerliğine ilişkin bulgular faktör analizi yöntemi ile sağlanmıştır. AFA ve DFA sonuçları ölçeğin yapısının iki faktörlü model ile daha iyi açıklandığını göstermiştir. Derin Öğrenme boyutu için Cronbach Alpha güvenirlik katsayısı 0.78 bulunurken, Yüzeysel Öğrenme için 0.74 bulunmuştur. Elde edilen sonuçlar, ölçeğin Türkiye’de de kullanılabileceğini göstermiştir

Smartphone addiction proneness in relation to sleep and morningness–eveningness in German adolescents

Background Mobile phones are an important part of adolescents’ life. In this study, the relationships among smartphone addiction, age, gender, and chronotype of German adolescents were examined. Materials and methods Two studies focused on two different measures of smartphone addiction. The Smartphone Addiction Proneness Scale (SAPS) was applied to 342 younger adolescents (13.39 ± 1.77; 176 boys, 165 girls, and 1 not indicated) in Study 1 and the Smartphone Addiction Scale was applied to 208 older adolescents (17.07 ± 4.28; 146 girls and 62 boys) in Study 2, both samples in southwest Germany. In addition, a demographic questionnaire and the Composite Scale of Morningness (CSM) and sleep measures were implemented. Results The most remarkable result of this study was that morningness–eveningness (as measured by CSM scores) is an important predictor for smartphone addiction; even stronger than sleep duration. Evening oriented adolescents scored higher on both smartphone addiction scales. In addition, gender is an important predictor for smartphone addiction and girls are more prone to become addicted. In addition, while sleep duration on weekdays negatively predicted SAPS, age, sleep duration on weekends, and midpoint of sleep on weekdays and weekends did not predicted smartphone addiction in both scales. The analysis of covariance revealed statistically significant effects of the covariates gender and age in both studies, as well as the main effect of chronotype. According to the t-test results, girls had higher scores than boys in smartphone addiction. Conclusion Evening types and girls are more prone to become smartphone addicted

Psychometric properties of sleep quality scale and sleep variables questionnaire in Turkish student sample

Sleep is a physiological need that affects physical and mental performances. However, the number of individuals who experience problems related directly or indirectly with sleep is increasing in many countries. Therefore, it is important to have a short, reliable and valid measure to assess both sleep quality and sleep related variables in school-age children. This study aims to carry out the validity and reliability studies for the Sleep Quality Scale and Sleep Variables Questionnaire (SQS-SVQ) used to determine sleep quality, parental control, total sleep time, mid-point of sleep and sleep efficiency and to adapt it into Turkish. The SQS-SVQ consists of seven scale items to measure sleep quality and eight questionnaire items. The validity and reliability studies of the instrument were carried out on data acquired from 4th-8th graders. Factorial validity for SQS and criterion related validity analyses were carried out for the validity of the SQS-SVQ and correlations ranged from 0.51 to 0.73. These analysis results put forth that the scale is a valid measurement tool. Internal consistency coefficient of the SQS was 0.72 and test-retest correlations of the SQS-SVQ ranged from 0.67 to 0.88. These acquired results indicated that the scale is reliable. Meanwhile, gender measurement invariance was tested for SQS and results indicated that gender measurement invariance was established. These results have shown that the SQS-SVQ can be used in social researches and especially in educational studies

Morningness-eveningness preferences and university entrance examination scores of high school students

This study explored whether morningness-eveningness preference influences achievement in a standardised university entrance examination. A total of 235 senior high school students aged 17-19 years responded to the Morningness-Eveningness Questionnaire (MEQ). The obtained MEQ responses indicated that out of 235 participants, 19.1% were "moderately morning" type, 68.1% were "neither" type, 11.9% were "moderately evening" type and 0.9% were "definitely evening" type (there was no "definitely morning" type student in the sample). A significant correlation was observed between MEQ scores and university entrance examination scores. In addition, morningness-eveningness preference was found to effect success in a university entrance examination. "Morning" type students performed better compared to "neither" type and "evening" type students, indicating that students with "morning" type circadian preference are at an advantage because of the starting time of the university entrance examination. (C) 2010 Elsevier Ltd. All rights reserved

Association of dietary patterns with circadian preference, sleep and personality in high school students

Unhealthy dietary patterns are increasing in adolescence in the modern era, so it is important to investigate variables that associate with dietary patterns. This study aimed to analyse the association of dietary patterns with circadian preference, sleep and personality in high school students. Moreover, the change in dietary pattern with respect to circadian preference, breakfast skipping and sleep quality was also examined. Four thousand nine hundred and seventy-one high school students with the age ranged 14-18 participated in to the current study. The results indicated that breakfast skipping, circadian preference, sleep quality, average sleep length, social jetlag, the midpoint of sleep in free days corrected, conscientiousness, agreeableness and emotional stability are associated factors of dietary patterns. Meanwhile circadian preference x breakfast skipping interaction effect was significant. It was also found that nearly one-fourth of the students are in the high risk level dietary pattern. As a conclusion sleeping well, being a morning type, being conscientiousness generally improve healthier dietary patterns and decrease breakfast skipping