Physical Sciences and Mathematics Commons^™

Synthesis, Characterization And Evaluation Of Lectin-Binding Properties Of 1,2-Cis-Glycosides, Bo Meng

Doctoral Dissertations

This dissertation presents a state-of-the-art research of 1,2-cis-glycosides, including synthetic methodology development, combinatorial total synthesis of galactoside ligands, construction of glycomicroarray surfaces, and quantitative evaluation of carbohydrate–lectin binding properties.

In Chapter 1, as a general introduction, various strategies that have been developed for the stereoselective construction of 1,2-cis-O-glycosidic bond are reviewed. 1,2-cis-O-Glycoside structural units are ubiquitous in nature, and they are extensively involved in numerous biological activities. The systematic identification and evaluation of the roles of carbohydrates usually relies on practical synthetic approaches to afford pure carbohydrates in considerable quantities. …

Strategies For Photochemical And Thermal Modification Of Materials, Sara Ghiassian

Electronic Thesis and Dissertation Repository

The modification of materials/surfaces is central to numerous applications ranging from opto-electronic devices to biomedical implants and drug delivery. Thus, there exists a high motivation for improving the methodologies which can be employed in order to modify surfaces in a selective and efficient fashion. One of the major goals of surface engineering is to control the chemical composition at the material interface. The fine control of the surface properties is a field of intense research as the performance of functional materials is strongly related to the processes and interactions that are occurring at the materials’ interface.

In general, the modification …

Synthesis And Characterization Of Five New Tetrakis(N-Phenylacetamidato) Dirhodium(Ii) Amine Complexes And One Molybdenum Cofactor Described Crystallographically, Cragin K. Harris

Electronic Theses and Dissertations

Six new crystal structures were determined using a Rigaku Mercurcy 375/MCCD(XtaLab mini) diffractometer. The structure of a molybdenum cofactor was solved resulting in an R1 (R1 = Σ ||Fo| - |Fc|| / Σ |Fo|) of 3.61% despite the presence of a disordered DMSO molecule. New Tetrakis(N-phenylacetamidato) Dirhodium(II) complexes were synthesized and characterized. Two 2,2-cis-[Rh2(NPhCOCH3)4]•(C3H4N2)x where x= 1 or 2 were successfully crystallized and solved with R1 values below 5%. Additional studies were conducted via NMR to observe formation of both products. Three potential catalysts were synthesized starting with 3,1-[Rh₂(NPhCOCH₃)₄]. The resulting compounds were a …

New Methods For Synthesis Of Organic Peroxides And Application Of Peroxide Electrophiles To Synthesis Of Functionalized Ethers, Shiva Kumar Kyasa

Department of Chemistry: Dissertations, Theses, and Student Research

New Method for Synthesis of Alkyl Hydroperoxides: There are a number of methods reported for synthesis of alkyl hydroperoxides, but most of them suffer either from poor yields or the formation of unwanted side products. I will be discussing new methodology for efficient synthesis of pure samples of 1° and 2° alkyl hydroperoxides via alkylation of readily available cyclododecanone 1,1-dihydroperoxide followed by hydrolysis of the resulting bis peroxyacetals.

Peroxide Electrophiles for Synthesis of Functionalized Ethers: Peroxides are underexplored functional groups as precursors for C-O bond formation and ether synthesis. The reactivity of dialkyl peroxides towards organometallics such as alkyl lithium …

Diels-Alder Synthesis Of Novel Heterocyclic Compounds, Including Inverse-Electron-Demand And Microwave Promotion, Kristen Richey

Honors Program Projects

One of the main subjects of this research is to compare “inverse-electron-demand” Diels-Alder (IED-DA) reactions with the classical, or “normal-electron-demand” (NED), DA reactions in an attempt to further define the line between the two. The other main focus is to compare methods using conventional heat with using microwave promotion. In both cases, the goal was to produce novel heterocyclic compounds.

Kinetics And Performance Studies Of A Switchable Solvent Tmg (1,1,3,3-Tetramethylguanidine)/1-Propanol/Carbon Dioxide System, Özge Yüksel, Mustafa Çağdaş Öztürk, Ayça Şeker, Erdoğan Alper

Turkish Journal of Chemistry

The rate constants and the activation energies of the reaction between carbon dioxide and 1,1,3,3-tetramethylguanidine (TMG) in 1-propanol solution were measured by a stopped-flow technique at a temperature range of 288--308 K and at a TMG concentration range of 2.5--10.0 wt %. Based on the pseudo-first-order reaction for CO_2, the reaction was modeled by a termolecular reaction mechanism, which resulted in a rate constant of 199.30 m^3 kmol^{-1} s^{-1} at 298 K. The activation energies were 5.19 kJ/mol and 5.26 kJ/mol at 2.5 and 5.0 wt % TMG, respectively. In addition, carbon dioxide absorption capacity was investigated using a gas--liquid …

Microwave-Assisted Regioselective [1,3]-Dipolar Cycloaddition Of 3-Methyl-2-(Substitutedbenzylidene)-5-Oxopyrazolidin-2-Ium-1-Ides To Benzothiophene 1,1-Dioxide, Yaşar Dürüst, Eda Sağirli, Akin Sağirli

Turkish Journal of Chemistry

A series of pyrazolidinium ylides was reacted with benzothiophene 1,1-dioxide to afford (3R,5S,5aS,10bS)-3-methyl-5-substitutedphenyl-2,3,5,5a-tetrahydrobenzo[4,5]thieno[3,2-c]pyrazolo[1,2-a]pyrazol-1(10bH)-one 6,6-dioxides under microwave irradiation and their structures were identified by means of spectral/physical characteristics including X-ray diffraction data and HRMS measurements.

Microwave-Assisted Synthesis Of Novel 8-Chloro-[1,2,4]Triazolo[4,3-$A$]Pyridine Derivatives, Linjiong Zhang, Mingyan Yang, Beizhen Hu, Zhaohui Sun, Xinghai Liu, Jianquan Weng, Chengxia Tan

Turkish Journal of Chemistry

A series of novel 1,2,4-triazolo[4,3-$a$]pyridine derivatives were synthesized from 2,3-dichloropyridine and hydrazine hydrate as starting materials by multistep reactions under microwave assistance, and their structures were characterized by $^{1}$H NMR, MS, and elemental analysis. This method provides several advantages such as high yields, facile work-up, and environmental friendliness.

Microwave-Assisted Synthesis Of Condensed 1,4-Dihydropyridines As Potential Calcium Channel Modulators, Erdem Kami̇l Özer, Mi̇yase Gözde Gündüz, Ahmed El-Khouly, Mehmet Yildirim Sara, Rahi̇me Şi̇mşek, Alper Bektaş İski̇t, Osman Ci̇hat Şafak

Turkish Journal of Chemistry

This study reports the design, synthesis, and calcium channel modulatory activity evaluation of a series of 14 novel fused 1,4-dihydropyridine derivatives. The molecular design of the compounds was based on modifications of nifedipine, which is a calcium channel blocker. The compounds were achieved by one-pot microwave-assisted reaction of 4,4-dimethyl-1,3-cyclohexanedione, 5-chlorosalicylaldehyde/3,5-dichlorosalicylaldehyde, an appropriate alkyl acetoacetate, and ammonium acetate in ethanol according to a modified Hantzsch reaction. The structures of the compounds were confirmed by spectral methods and elemental analysis. To evaluate their relaxant activities, the maximum relaxant response (E$_{\max})$ and pD$_{2}$ values of the compounds and nifedipine were determined on isolated …

Superior Intrinsic Thermoelectric Performance With Zt Of 1.8 In Single-Crystal And Melt-Quenched Highly Dense Cu2-Xse Bulks, Lanling Zhao, Xiaolin Wang, Ji-Yang Wang, Zhenxiang Cheng, S X. Dou, Jun Wang, L Liu

Australian Institute for Innovative Materials - Papers

Practical applications of the high temperature thermoelectric materials developed so far are partially obstructed by the costly and complicated fabrication process. In this work, we put forward two additional important properties for thermoelectric materials, high crystal symmetry and congruent melting. We propose that the recently discovered thermoelectric material Cu2-xSe, with figure of merit, zT, over 1.5 at T of ~ 1000 K, should meet these requirements, based on our analysis of its crystal structure and the Cu-Se binary phase diagram. We found that its excellent thermoelectric performance is intrinsic, and less dependent on grain size, while highly dense samples can …

Synthesis Of 5-Aryl-$N$-(Trichloroacetyl)-1,3,4-Oxadiazole-2-Carboxamide Via Three-Component Reaction Of Trichloroacetyl Isocyanate, ($N$-Isocyanimino)Triphenylphosphorane, And Benzoic Acid Derivatives, Nahid Shajari, Ali Reza Kazemizadeh, Ali Ramazani

Turkish Journal of Chemistry

The three-component reaction of benzoic acid derivatives, ($N$-isocyanimino)triphenylphosphorane, and trichloroacetyl isocyanate in a 1:1:1 ratio in CH$_{3}$CN occurred at room temperature, and the 5-aryl-$N$-(trichloroacetyl)-1,3,4-oxadiazole-2-carboxamide derivatives produced were formed in high yields. The reaction proceeded smoothly and cleanly under mild reaction conditions and no side reactions were observed. The structures of the products were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, mass spectroscopy, and elemental analysis.