Physical Sciences and Mathematics Commons^™

Synthetic Approaches Of Carbohydrate Based Self-Assembling Systems, Guijun Wang, Anji Chen, Pramod Aryal, Jonathan Bietsch

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based self-assembling systems are essential for the formation of advanced biocompatible materials via a bottom-up approach. The self-assembling of sugar-based small molecules has applications encompassing many research fields and has been studied extensively. In this focused review, we will discuss the synthetic approaches for carbohydrate-based self-assembling (SA) systems, the mechanisms of the assembly, as well as the main properties and applications. This review will mainly cover recent publications in the last four years from January 2020 to December 2023. We will essentially focus on small molecule self-assembly, excluding polymer-based systems, which include various derivatives of monosaccharides, disaccharides, and oligosaccharides. Glycolipids, …

Para-Methoxybenzylidene Acetal-Protected D-Glucosamine Derivatives As Ph-Responsive Gelators And Their Applications For Drug Delivery, Jonathan Bietsch, Logan Baker, Anna Duffney, Alice Mao, Mary Foutz, Cheandri Ackermann, Guijun Wang

Chemistry & Biochemistry Faculty Publications

Carbohydrate-based low molecular weight gelators (LMWGs) are compounds with the capability to self-assemble into complex molecular networks within a solvent, leading to solvent immobilization. This process of gel formation depends on noncovalent interactions, including Van der Waals, hydrogen bonding, and π–π stacking. Due to their potential applications in environmental remediation, drug delivery, and tissue engineering, these molecules have emerged as an important area of research. In particular, various 4,6-O-benzylidene acetal-protected D-glucosamine derivatives have shown promising gelation abilities. In this study, a series of C-2-carbamate derivatives containing a para-methoxy benzylidene acetal functional group were synthesized and characterized. These compounds exhibited good …

Oligocarbonate Molecular Transporters: Oligomerization-Based Syntheses And Cell-Penetrating Studies, Christina B. Cooley, B. M. Trantow, F. Nederberg, M. K. Kiesewetter, J. L. Hedrick, R. M. Waymouth, P. A. Wender

Christina B Cooley

A new family of guanidinium-rich molecular transporters featuring a novel oligocarbonate backbone with 1,7-side chain spacing is described. Conjugates can be rapidly assembled irrespective of length in a one-step oligomerization strategy that can proceed with concomitant introduction of probes (or by analogy drugs). The new transporters exhibit excellent cellular entry as determined by flow cytometry and fluorescence microscopy, and the functionality of their drug delivery capabilities was confirmed by the delivery of the bioluminescent small molecule probe luciferin and turnover by its intracellular target enzyme.

Natural Kinds And Ceteris Paratis Generalizations: In Praise Of Hunches, W. Christropher Boyd, Richard N. Boyd

Chemistry Faculty Publications

According to stereotypical logical empiricist conceptions, scientific findings are approximately true (or perhaps true ceteris paribus) law-like generalizations used to predict natural phenomena. They are deployed using topic-neutral, generally reliable inferential principles like deductive or statistical inferences. Natural kinds are the kinds in such generalizations. Chemical examples show that such conceptions are seriously incomplete. Some important chemical generalizations are true often enough, even though not usually true, and they are applied using esoteric topic- and discipline-specific inference rules. Their important methodological role is to underwrite often-enough reliable, often socially implemented, scientifically informed guessing about chemical phenomena. Some chemical natural …

Application Of The Picoloyl Substituent In Carbohydrate Chemistry, Michael Mannino, Alexei V. Demchenko

Michael Mannino

Application Of The Picoloyl Group In Carbohydrate Chemistry, Michael Mannino

Dissertations

Stereocontrol of glycosylation reactions is a constant struggle in the field of synthetic carbohydrate chemistry. The application of the picoloyl (Pico) substituent can offer numerous stereocontrolling avenues. The most popular application is the Hydrogen-bond-mediated Aglycone Delivery (HAD) method that provides excellent selectivity in the glycosylation of a variety of sugar substrates. The HAD method relies on the formation of an intermolecular hydrogen bond between the nitrogen atom of the Pico substituent on the glycosyl donor with the hydroxyl group of the glycosyl acceptor. This interaction provides a facial preference for the nucleophilic attack and hence provides powerful stereocontrol for the …

Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal

Turkish Journal of Chemistry

A novel green approach for the synthesis of silver nanoparticles using erythromycin as a reducing/capping agent is presented. Erythromycin-derived silver nanoparticles were characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Monodispersed silver nanoparticles showed excellent and promising catalytic activity for reduction of 3 differently charged dyes (eosin B, methylene blue, and rose bengal) in the presence of NaBH_4. The study revealed that 100% reduction of these dyes can be achieved efficiently in just 150--250 s. They were easily recovered from the reaction medium and were reused 5 times, …

The Design And Synthesis Of Magnetic Nanocomposites, Daniel Hudgins

Theses and Dissertations

Magnetism lies at the core of modern technology and can be found in industries such as oil refining, automotive, telecommunications, personal electronics, and power generation that are integral to our day to day lives. This permeation into everyday life has been enhanced in the past several decades with improvements in material design based upon the principles of nanotechnology leading to smaller, faster, and more efficient devices. The presented research will discuss the synthesis and processing of multiple magnetic nanoparticle structures designed for the enhancement of various, application specific, properties. In the first experiments a tunable core/shell structure was developed with …

Surfactant-Controlled Aqueous Synthesis Of Sno_2 Nanoparticles Via The Hydrothermal And Conventional Heating Methods, Muhammad Akhyar Farrukh, Heng Boon Teck, Rohana Adnan

Turkish Journal of Chemistry

Tin oxide nanoplates and nanoballs were fabricated using a cationic surfactant of cetyltrimethylammonium bromide (CTABr) as an organic supramolecular template and tin(IV) chloride as an inorganic precursor via the hydrothermal and conventional heating methods. Urea, which decomposes to ammonium and hydroxide ions during hydrolysis, was used as the source of slow homogeneous precipitation of Sn^{4+} with OH^- to control the particle size. The influence of different reaction parameters (time, temperature, and ratio of Sn^{4+} to CTABr) on particle sizes, particle distribution, and morphology was investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. XRD …

Oligocarbonate Molecular Transporters: Oligomerization-Based Syntheses And Cell-Penetrating Studies, Christina B. Cooley, B. M. Trantow, F. Nederberg, M. K. Kiesewetter, J. L. Hedrick, R. M. Waymouth, P. A. Wender

Chemistry Faculty Research

A new family of guanidinium-rich molecular transporters featuring a novel oligocarbonate backbone with 1,7-side chain spacing is described. Conjugates can be rapidly assembled irrespective of length in a one-step oligomerization strategy that can proceed with concomitant introduction of probes (or by analogy drugs). The new transporters exhibit excellent cellular entry as determined by flow cytometry and fluorescence microscopy, and the functionality of their drug delivery capabilities was confirmed by the delivery of the bioluminescent small molecule probe luciferin and turnover by its intracellular target enzyme.

Air And Water Free Solid-Phase Synthesis Of Thiol Stabilized Au Nanoparticles With Anchored, Recyclable Dendrimer Templates, John D. Gilbertson, G. Vijayaraghavan, K. J. Stevenson, Bert D. Chandler

Chemistry Faculty Research

Solid-phase synthetic templates for Au nanoparticles were developed using Merrifield resins and polyamidoamine (PAMAM) dendrimers. This synthetic scheme affords the opportunity to prepare metal nanoparticles in the absence of air and water, and it does not necessitate phase transfer agents that can be difficult to remove in subsequent steps. Amine-terminated generation 5 PAMAM (G5NH2) dendrimers were grafted to anhydride functionalized polystyrene resin beads and alkylated with 1,2-epoxydodecane to produce G5C12anch. The anchored dendrimers bound both CoII and AuIII salts from toluene solutions at ratios comparable to those of solution phase alkyl-terminated PAMAM dendrimers. The encapsulated AuIII salts could be reduced …