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Öğe Chiral mono and diamide derivatives of calix[4]arene for enantiomeric recognition of chiral amines(WILEY-BLACKWELL, 2008) Kocabaş, Erdal; Durmaz, Mustafa; Alpaydın, Sabri; Sirit, Abdulkadir; Yılmaz, MustafaNovel chiral mono and diamide derivatives of calix[4]arene have been prepared from the aminolysis reaction of 5,11,17,23-tetra-tert-butyl-25,27-dietboxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 1 and 25,27-diethoxycarbonyl-methoxy-26,28-dihydroxycalix[4]arene 2 with chiral (S)-(-)-1-phenylethylamine (PEA) and (1S,2S)-(+)-2-amino-1-(4-nitrophenyl)-1,3-propanediol, respectively. Spectrophotometric titrations have been performed in CHCl3 at 20-30 degrees C in order to obtain the binding constants (K) and the thermodynamic quantities (Delta H and Delta S) for the stoichiometric 1:1 inclusion complexation of various chiral amines with these new host compounds. Preliminary experiments were undertaken to confirm the complexation properties of receptors 9 and 13 with PEA by H-1 NMR in CDCl3 at room temperature. The molecular recognition abilities and enantioselectivities for guests (R and S)-(x-PEA and (R and S)-cyclohexylethylamine (CHEA) are discussed from a thermodynamic point of view.Öğe Kaliks[4]arenlerin homokiral amit türevlerinin sentezi ve enantiyomerlerin tanınmasında kullanılması(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2007-10-19) Kocabaş, Erdal; Sırıt, AbdulkadirBu çalışmada p-t-bütilkaliks[4]aren ve kaliks[4]aren'in kiral sekiz yeni amit türevi (5-8, 9-12); 5,11,17,23-tetra-ter-bütil-25,27 dietoksikarbonilmetoksi-26,28- dihidroksi kaliks[4] aren (3) ve 25,27 dietoksikarbonilmetoksi-26,28-dihidroksi kaliks[4] aren (4) ile 2- amino-1-butanol, fenil glisinol, 3-fenil-1-amino-propanol ve (1S,2S)-(+)-2-amino-1-(4-nitrofenil)-1,3-propandiol amino alkolleri tepkimeye sokularak elde edilmiştir. Kaliks[4]arenin kiral amit türevleri kiral aminlerin moleküler tanınma çalışmalarında ve amino asitlerin faz transfer ekstraksiyonunda kullanılmıştır. Ayrıca bu bileşiklerden 10 ve 12' nin feniletil amin ve 1,2-propandiol guestlerine karşı kiral tanınma özellikleri 1H NMR spektroskopisi kullanılarak incelenmiştir. Gerçekleştirilen tüm reaksiyonlar İTK ile izlenmiş ve elde edilen ürünler kolon kromatografisi ile saflaştırılarak yapıları IR ve 1H NMR, 13C NMR ve FAB MS teknikleriyle aydınlatıldıktan sonra kiral bileşiklerin optik çevirme açıları ölçülmüştür.Öğe A Novel Benzothiazole Based Azocalix[4]arene as a Highly Selective Chromogenic Chemosensor for Hg2+ İon: A Rapid Test Application in Aqueous Environment(Elsevier Science Bv, 2010) Bingöl, Haluk; Kocabaş, Erdal; Zor, Erhan; Coşkun, AhmetA novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthesized as chromogenic chemosensor, and its binding and sensing properties with heavy metal ions (Pb2+, Hg2+, Ni2+, Cd2+, Cu2+, Zn2+, Co2+, Fe2+, Mn2+, Cr3+, Ag+) were investigated by UV-vis spectroscopy and voltammetric techniques. The results of spectroscopic and voltammetric experiments showed that the chromogenic chemosensor has high selectivity towards Hg2+ ion over the other heavy metal ions. Moreover, it was shown that the interaction between Hg2+ and the chromogenic chemosensor occurs by means of the benzothiazole azo groups at the upper rim by using differential pulse voltammetry. The stoichiometric ratio and the association constant were determined as 1:1 and (6.1 +/- 0.3) x 10(5) L mol(-1) for the complex between Hg2+ and the ionophore. Furthermore, we prepared a rapid test kit for early detection of Hg2+ in aqueous environment in the concentration range of 1 x 10(-4) to 1 x 10(-2) M.Öğe A Rapid and High-Yielding Synthesis of Thiazoles and Aminothiazoles Using Tetrabutylammonium Salts(Pergamon-Elsevier Science Ltd, 2010) Kocabaş, Erdal; Sarıgüney, Ahmet Burak; Coşkun, AhmetA convenient method for the synthesis of thiazoles and aminothiazoles by treatment of phenacyl bromides with thioamides/thiourea in the presence of tetra butylammonium hexafluorophosphate (Bu4NPF6) at room temperature was developed. The products having high yields were formed rapidly (within 15 min). The method is simple, rapid and practical, generating thiazole derivatives in excellent isolated yields. The structures of the newly synthesized products were identified by FT-IR, H-1 NMR, C-13 NMR spectroscopy and elemental analysis data.Öğe Selective sodium ion transfer across a water/1,2-dichloroethane micro-interface by a calix[4]arene derivative(ELSEVIER SCIENCE SA, 2011) Kaykal, Ferhat; Kocabaş, Erdal; Bingöl, Haluk; Akgemci, Emine Güler; Coşkun, AhmetThe transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 25,27-di [(2-ethoxy)benzaldehyde]-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl) calix[4]arene (DBC4), across a water/1,2-dichloroethane (1,2-DCE) micro-interface supported at the tip of a micropipette was investigated. The well-defined voltammetric behavior was obtained only for Na+ ion among the used metal ions by using the electrochemical methods. The measurements were performed when the bulk concentration of Na+ ion in the aqueous phase is much higher than that of DBC4 in the organic phase, and vice versa. The diffusion coefficient of DBC4 in the DCE phase was calculated to be equal to (4.2 +/- 0.2) x 10(-6) cm(2) s(-1). The logarithm of the association constant of DBC4-Na+ complex having 1:1 stoichiometry in 1,2-DCE was determined as 3.99. The differential pulse voltammetry was used for amperometric detection of Na+ ion in chloride medium. The results show that DBC4 can be used for many analytical applications such as ion recognition and fabrication of electrochemical sensor for Na+ ion because of its good selectivity. (C) 2011 Elsevier B.V. All rights reserved.Öğe Synthesis and dichromate anion sorption of silica gel-immobilized calix[4]arenes(ELSEVIER SCIENCE BV, 2009) Bozkurt, Selahattin; Kocabaş, Erdal; Durmaz, Mustafa; Yılmaz, Mustafa; Sirit, AbdülkadirThree new silica gel-immobilized calix[4]arene polymers 9-11 have been prepared via modification of calix[4]arene mono amido derivatives 3-5 with 3-aminopropyl triethoxysilane (APTES) and activated silica gel, respectively. The polymers were characterized by Fourier transform infrared spectroscopy, elemental analysis and thermal gravimetric analysis. The solid-liquid extraction properties of ligands 3-5 along with their immobilized derivatives 9-11 towards dichromate (HCr2O7-/Cr2O72-) anions were reported. It was found that these calix[4]arene-based polymers have high extraction abilities towards dichromate anions as compared to their monomeric precursors. (C) 2008 Elsevier B.V. All rights reserved.Öğe Synthesis of new chiral calix[4]arene diamide derivatives for liquid phase extraction of alpha-amino acid methylesters(PERGAMON-ELSEVIER SCIENCE LTD, 2006) Kocabaş, Erdal; Karaküçük, Ayşegül; Sirit, Abdülkadir; Yılmaz, MustafaThe synthesis of chiral diamide derivatives of calix[4]arene from the reaction of p-tert-butylcalix[4]arene diester la and calix[4]arene diester 1b with various amino alcohols were reported. The H-1 and C-13 NMR, data showed that the compounds synthesized exist in the cone conformation. The extraction study properties of these new compounds 3a,b-4a,b towards some selected alpha-amino acid methylesters are also reported. (c) 2006 Elsevier Ltd. All rights reserved.Öğe Veteriner Hekimlikte Nanoteknoloji(2019) Altav, Yiğit; Baş, Ahmet Levent; Erci, Fatih; Kocabaş, ErdalNanoteknoloji, biyoloji, biyoteknoloji, tıp ve veteriner hekimliği alanlarındaki uygulamalar için yeni bakış açısı ortaya çıkarmaktadır.Hayvan sağlığı ve üretiminde mükemmellik, hayvanlar için etkili uygulamalar ve ürünler oluşturmak amacıyla nanoteknolojinin kullanımıyeni olanaklar sağlamaktadır. Nano ölçekte madde üretme ve manipüle etme kabiliyeti, veteriner hekimliğin çeşitli alanlarında uygulamaiçin fırsatlar sunmaktadır. Veteriner hekimlikte özellikle ilaç formülasyonlarında ve diğer ilgili alanlarda yaygın olarak kullanılannanomalzemeler, polimerik nanopartiküller, dendrimerler, lipozomlar, metalik nanopartiküller ve nanoemülsiyonlardan oluşmaktadır.Akıllı ilaç taşıyıcı sistemler, nanoaşılar, nanoterapötikler ve adjuvanlar hayvan sağlığı ve üretiminde devrim potansiyeline sahiptir.Nanomalzemeler, hastalık teşhisi, tedavisi, ilaç hedefleme ve iletimi, hayvan beslenmesi, hayvan ıslahı, üreme, doku mühendisliği vehayvansal ürünlere katma değer için sayısız uygulama alanı oluşturmaktadır. Önümüzdeki yıllarda, nanoteknolojide devam edenaraştırmalar hayvan sağlığı bilimini ve teknolojisini yenileyecek ve hayvan üretimini artırmaya yardımcı olacaktır. Veteriner hekimliktenanoteknoloji, tanı, tedavi ve ayrıca moleküler ve hücresel üreme için yeni gelişmeler sağlama potansiyeline sahiptir.Öğe Voltammetric characterization of selective potassium ion transfer across micro-water/1,2-dichloroethane interface facilitated by a novel calix[4]arene derivative(PERGAMON-ELSEVIER SCIENCE LTD, 2011) Durmaz, Müge; Zor, Erhan; Kocabaş, Erdal; Bingöl, Haluk; Akgemci, Emine GülerIn this study, transfer reactions of alkali and alkaline-earth metal ions across a micro-water/1,2-dichloroethane (1,2-DCE) interface facilitated by a novel calix[4]arene derivative, 5,11,17,23-tetra-tert-butyl-25,27-bis(2'amino-methylpyridine)-26,28-dihydroxy calix[4]arene (APHC4), were investigated by cyclic and differential pulse voltammetry techniques. Well-defined voltammetric behavior was obtained only for K(+) ion among the used metal ions. The electrochemical data were used to determine the stoichiometry and the appropriate association constant of the occurring complex between K(+) ion and APHC4. The obtained steady-state voltammograms indicated that the facilitated transfer process occurs with a TIC/TID mechanism according to 1:1 stoichiometry. The logarithm of the association constant (log beta(0)(1)) of K(APHC4)(+) complex in the DCE phase was calculated to be 6.32. Also, the availability of the facilitated transfer for the design of an amperometric screening sensor for K(+) ion was evaluated in the range of 50-500 mu mol dm(-3). (C) 2011 Elsevier Ltd. All rights reserved.
