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Development Of Novel Chemical Tools For Proteasome Biology & A New Approach To 1-Azaspirocyclic Ring System, Lalit Kumar 2012 University of Kentucky

Development Of Novel Chemical Tools For Proteasome Biology & A New Approach To 1-Azaspirocyclic Ring System, Lalit Kumar

Theses and Dissertations--Chemistry

The proteasome, a multiprotease complex, is clinically validated as an anticancer target by the FDA approval of bortezomib and carfilzomib for the treatment of multiple myeloma. The emergence of resistance to proteasome inhibitors however remains a major clinical challenge. Recently, distinct types of proteasomes termed ‘intermediate proteasomes’, which contain unconventional mixtures of catalytic subunits, have been implicated with drug resistance of tumor cells. In elucidating the role of intermediate proteasomes in drug resistance, a crucial step is to unequivocally determine the subunit composition of intermediate proteasomes in cells. With this in mind, the goal of the studies reported in this ...


Novel Aromatic Ion–Pairs: Synergy Between Electrostatics And Π-Face Aromatic Interactions, Pramod Prasad Poudel 2012 University of Kentucky

Novel Aromatic Ion–Pairs: Synergy Between Electrostatics And Π-Face Aromatic Interactions, Pramod Prasad Poudel

Theses and Dissertations--Chemistry

This dissertation focuses on the design and study of charged aromatic molecules where weak π-π interactions synergize with electrostatic interactions to enhance the overall interaction between aromatic moieties. Each chapter investigates some aspect of this hypothetical synergy between electrostatics and π-face aromatic cohesion.

The first chapter unveiled the importance of electrostatics in the intramolecular stacking of flexible aromatic molecular templates 1-2Br and 2a. While our previous studies found dicationic molecular template 1-2Br to have intramolecular π-stacking between electron poor pyridinium and electron rich xylylene moieties, no such stacking interaction was observed in the neutral analog 2a.

Chapter two systematically explored ...


Metal-Catalyzed And Aryne-Mediated Multicomponent Approaches To Heterocycles, Nataliya Alexandrovna Markina 2012 Iowa State University

Metal-Catalyzed And Aryne-Mediated Multicomponent Approaches To Heterocycles, Nataliya Alexandrovna Markina

Graduate Theses and Dissertations

Over the course of the work described in this dissertation, several novel methodologies have been successfully developed and applied to the synthesis of medicinally-relevant heterocycles, including indoles, benzo[b]furans, 1,2-dihydroisoquinolines, 1H-indazoles, and pyrido[1,2-a]indoles. In these methods, well-studied transition metal-catalyzed processes and newly discovered aryne-mediated processes have been found applicable and efficient when applied to the synthesis of a variety of heterocycles. Most of these processes have also been transformed into multicomponent processes.


A Discovery-Oriented Approach To Solid-Phase Peptide Synthesis, Brian Brennan, Matthew Bockman, Christopher Miedema 2012 Illinois Wesleyan University

A Discovery-Oriented Approach To Solid-Phase Peptide Synthesis, Brian Brennan, Matthew Bockman, Christopher Miedema

Scholarship

In this discovery-oriented laboratory experiment, students use solid-phase synthesis techniques to construct a dipeptide containing an unknown amino acid. Following synthesis and cleavage from the polymeric support, electrospray ionization-mass spectrometry is employed to identify the unknown amino acid that was used in the peptide coupling. This experiment, performed in two, 3-h laboratory periods, provides an opportunity for students to learn the technique of solid-phase peptide synthesis and to critically evaluate data that they generate in the laboratory. The experiment is suitable for second-semester organic chemistry students as they learn methods for the formation of amide bonds or upper-level biochemistry students ...


Synthesis Of Polyphenols And Azafluorenones, Aaron Michael Kempema 2012 Iowa State University

Synthesis Of Polyphenols And Azafluorenones, Aaron Michael Kempema

Graduate Theses and Dissertations

The synthesis of 1,3,4,5-tetragalloylapiitol was accomplished in 7 steps. A direct synthesis of natural and unnatural ellagitannins were made using an intramolecular oxidative coupling. Different flavonols were synthesized via a novel base-mediated cyclization step, which was strategically different than previous ways to make flavonols. A three step synthesis of azaflureones was developed.


Novel Aryne-Mediated Synthetic Methodologies, Anton Vladimirovich Dubrovskiy 2012 Iowa State University

Novel Aryne-Mediated Synthetic Methodologies, Anton Vladimirovich Dubrovskiy

Graduate Theses and Dissertations

Using readily available substrates, a variety of medicinally and biologically important molecules can now be easily prepared by a one-pot transformation involving a reaction with aryne intermediates. The highly reactive arynes have been generated from commercially available or readily prepared o-(trimethylsilyl)aryl triflates and a fluoride source under relatively mild conditions.


Design, Synthesis And Evaluation Of Novel Diazirine Photolabels With Improved Ambient Light Stability And Fluorous-Based Enrichment Capacity, Arun Babu Kumar 2012 University of South Florida

Design, Synthesis And Evaluation Of Novel Diazirine Photolabels With Improved Ambient Light Stability And Fluorous-Based Enrichment Capacity, Arun Babu Kumar

Graduate Theses and Dissertations

Photoaffinity labeling is a quintessential technique in studying and analyzing the interaction between a ligand and receptor. Diazirines are one of the important photo-labile moieties used in photoaffinity labeling due to their superior photo labeling characteristics. Herein, we report the investigations we conducted with diazirine photolabels on (a) photochemical aspects leading to enhancement of their ambient light stability and (b) equipping them with fluorous tags to enable fluorous enrichment of labeled proteins. Furthermore, we report a pilot study to develop BACE-1 inhibitors, which have potential to be developed into photoaffinity probes.

3-Trifluoromethyl-3-phenyldiazirine offers good selectivity and protection against pseudolabeling but ...


N-Acyl Ciprofloxacins: Synthesis, Antibacterial Activity And Effects On Molecular Loading Of Poly(Vinyl Benzoate) Nanoparticles, Ryan Cormier 2012 University of South Florida

N-Acyl Ciprofloxacins: Synthesis, Antibacterial Activity And Effects On Molecular Loading Of Poly(Vinyl Benzoate) Nanoparticles, Ryan Cormier

Graduate Theses and Dissertations

Bacterial infections are becoming progressively more difficult to treat due to antibiotic resistance and the decreasing rate at which new antibiotics are brought to market. The Turos laboratory has attempted to tackle this problem for the last 15 years with the discovery of N-thiolated β-lactams leading to the design of polyacrylate nanoparticles to deliver these and other drugs. Chapter 1 discusses many reported instances of utilizing different types of polymeric nanoparticles to deliver antibiotics. Poly(lactic-co-glycolic acid) (PLGA), poly(alkyl cyanoacrylate) (PACA), poly(styrene-co-butylacrylate), and chitosan are the main polymers used to make nanoparticles. Chapter 2 describes the synthesis, antibacterial ...


Synthesis Of Natural Products And Small Molecules Using Quinones, Feng Liu 2012 Iowa State University

Synthesis Of Natural Products And Small Molecules Using Quinones, Feng Liu

Graduate Theses and Dissertations

Total synthesis of biologically active natural products has been used for the discovery of new medicines. In collaboration with biology and medicinal chemistry, it has led to discovery and the ensuing syntheses of biologically potent natural products, which have been translated into drug applications.

In this thesis, we explored both total synthesis and methodology of several natural products and small molecules, especially using quinone as starting materials. Chapter 2 describes an efficient synthesis of Bauhinoxepin J and polyhydroxylated xanthones via intramolecular radical cyclization, and a novel method of facile oxidation of 1,4-

hydroquinones to 1,4-benzoquinones by using N-Bromosuccinimide ...


Developing Benzobisazole-Containing Conjugated Polymers For Semiconducting Applications, Jeremy Joseph Intemann 2012 Iowa State University

Developing Benzobisazole-Containing Conjugated Polymers For Semiconducting Applications, Jeremy Joseph Intemann

Graduate Theses and Dissertations

Benzobisazoles are electron deficient moieties whose polymers are known to possess high thermal and mechanical strength. To date, howeverm they have not been well developed for semiconducting applications due to their poor solubility in organic solvents and an inability to functionalize these materials. This thesis describes the synthesis and properties of a variety of new benzobisazole-containing conjugated polymers and reports their performance in organic light-emitting diodes. The new polymers are soluble in common organic solvents and have been synthetically tuned to possess a wide variety of properties by copolymerizing benzobisazole with an assortment of different comonomers. Furthermore, the first examples ...


Automated Solution-Phase Synthesis Of Β-Mannans, Shu-Lun Tang 2012 Iowa State University

Automated Solution-Phase Synthesis Of Β-Mannans, Shu-Lun Tang

Graduate Theses and Dissertations

In order to provide a strategy which could produce the biologically important beta-mannans in a highly efficient and economical way, this dissertation illustrates the development of the automated solution-phase synthesis of different beta-mannans including the fungal beta-1,2-mannans by using both oxidation-reduction and beta-directing mannuronate strategies, and also reveals a new strategy for beta-mannan synthesis by reduction of mannuronate esters to alcohols. The following chapter shows the power of this automated solution-phase method to create beta-1,4-mannuronate and beta-1,4-mannan oligomers up to hexasaccharides. The subsequent chapter demonstrates the application of this new beta-mannan synthesis strategy for the synthesis of ...


Chiral Binol Metal Phosphate/Phosphoric Acid Catalyzed Enantioselective Addition Of Phosphorus And Sulfur Nucleophiles To Imines And Epoxides, Gajendrasingh Ingle 2012 University of South Florida

Chiral Binol Metal Phosphate/Phosphoric Acid Catalyzed Enantioselective Addition Of Phosphorus And Sulfur Nucleophiles To Imines And Epoxides, Gajendrasingh Ingle

Graduate Theses and Dissertations

The research presented in this dissertation focuses on chiral BINOL metal phosphatephosphoric acid catalyzed enantioselective additions of phosphorus and sulfur nucleophiles to imines and epoxides. In chapter 2, we reported a new method to synthesize chiral amino phosphine oxides. The reaction combines N-substituted imines and diphenylphosphine oxide catalyzed by chiral magnesium 9-antryl phosphate. A wide variety of aliphatic and aromatic aldimines substituted by electron neutral benzhydryl or dibenzocycloheptene groups were excellent substrates for the addition reaction. The imines protected with dibenzocycloheptene protecting group provided better enantioselectivity than those protected with benzhydryl group, while both imines gave comparable yields. Also ...


Asymmetric Intra- And Intermolecular Cyclopropanation By Co(Ii)- Based Metalloradical Catalysis, Xue Xu 2012 University of South Florida

Asymmetric Intra- And Intermolecular Cyclopropanation By Co(Ii)- Based Metalloradical Catalysis, Xue Xu

Graduate Theses and Dissertations

Metal-catalyzed cyclopropanation of olefins with diazo reagents has attracted research interest because of its fundamental and practical importance. The resulting cyclopropyl units are recurrent motifs in biologically important molecules and can serve as versatile precursors in organic synthesis. Since they were first introduced in 2004, Co(II) complexes of D2-symmetric chiral amidoporphyrins [Co(D2-Por*)] have emerged as a new class of catalysts for asymmetric cyclopropanation. These metalloradical catalysts have been shown to be highly effective for asymmetric intermolecular cyclopropanation of a broad scope of substrates with different classes of carbene sources, particularly including electron-deficient olefins and ...


Development And Optimization Of Kinetic Target-Guided Synthesis Approaches Targeting Protein-Protein Interactions Of The Bcl-2 Family, Sameer Shamrao Kulkarni 2012 University of South Florida

Development And Optimization Of Kinetic Target-Guided Synthesis Approaches Targeting Protein-Protein Interactions Of The Bcl-2 Family, Sameer Shamrao Kulkarni

Graduate Theses and Dissertations

Kinetic target-guided synthesis (TGS) and in situ click chemistry are among unconventional discovery strategies having the potential to streamline the development of protein-protein interaction modulators (PPIMs). In kinetic TGS and in situ click chemistry, the target is directly involved in the assembly of its own potent, bidentate ligand from a pool of reactive fragments. Herein, we report the use and validation of kinetic TGS based on the sulfo-click reaction between thio acids and sulfonyl azides as a screening and synthesis platform for the identification of high-quality PPIMs. Starting from a randomly designed library consisting of nine thio acids and nine ...


Enantioselective Brønsted And Lewis Acid-Catalyzed Reaction Methodology: Aziridines As Building Blocks For Catalytic Asymmetric Induction, Shawn E. Larson 2012 University of South Florida

Enantioselective Brønsted And Lewis Acid-Catalyzed Reaction Methodology: Aziridines As Building Blocks For Catalytic Asymmetric Induction, Shawn E. Larson

Graduate Theses and Dissertations

Chiral molecules as with biological activity are plentiful in nature and the chemical literature; however they represent a smaller portion of the pharmaceutical drug market. As asymmetric methodologies grow more powerful, the tools are becoming available to synthesize chiral molecules in an enantioselective and efficient manner.

Recent breakthroughs in our understanding of phosphoric acid now allow for Lewis acid catalysis via pairing with alkaline earth metals. Using alkaline earth metals with chiral phosphates is an emerging approach to asymmetric methodology, but already has an influential record.

The development of new conditions for the phosphoric acid-catalyzed highly enantioselective ring-opening of meso-aziridines ...


Design And Synthesis Of Protein-Protein Interaction Inhibitor Scaffolds, David B. Badger 2012 University of South Florida

Design And Synthesis Of Protein-Protein Interaction Inhibitor Scaffolds, David B. Badger

Graduate Theses and Dissertations

Many currently relevant diseases such as cancer arise from altered biological pathways that rely on protein-protein interactions. The proteins involved in these interactions contain certain functional domains that are responsible for the protein's biological activities. These domains consist of secondary structural elements such as α-helices and Β-sheets which are at the heart of the protein's biological activity. Therefore, designing drugs that inhibit protein-protein interactions by binding to these key secondary structural elements should provide an effective treatment for many diseases. Presented in this dissertation are the designs, syntheses, and biological evaluations for both novel α-helix and novel Β-sheet ...


Synthesis And Anti-Mrsa Activity Of Hydrophilic C3-Acylated N-Thiolated Β-Lactams And N-Acyl Ciprofloxacin-N-Thiolated Β-Lactam Hybrids, Biplob Bhattacharya 2012 University of South Florida

Synthesis And Anti-Mrsa Activity Of Hydrophilic C3-Acylated N-Thiolated Β-Lactams And N-Acyl Ciprofloxacin-N-Thiolated Β-Lactam Hybrids, Biplob Bhattacharya

Graduate Theses and Dissertations

The Turos laboratory has been working with N-thiolated β-lactams for years trying to understand the mode of action and structural features it needs to have biological activity. Over the years new data has shown promising inhibitory activity against various microbes.

In this dissertation, a review of the vast amount of work carried out on N-thiolated β-lactams in Turos laboratory has been done and their novelty, in terms of structure and mechanism has been discussed. A complete outline of our work in the discovery and ongoing development of these compounds, starting from our initial, unexpected finding of antimicrobial activity for one ...


Iron(Iii) Tosylate Catalyzed Acylation Of Alcohols, Phenols, And Aldehydes, Ram Mohan, Neil Baldwin, Anna Nord, Brendan O’Donnell 2012 Illinois Wesleyan University

Iron(Iii) Tosylate Catalyzed Acylation Of Alcohols, Phenols, And Aldehydes, Ram Mohan, Neil Baldwin, Anna Nord, Brendan O’Donnell

Scholarship

Iron(III) p-toluenesulfonate (tosylate) is an efficient catalyst for acetylation of alcohols, phenols, and aldehydes. The acetylation of 1° and 2° alcohols, diols, and phenols proceeded smoothly with 2.0 mol % of catalyst. However, the reaction worked well with only a few 3° alcohols. The methodology was also applicable to the synthesis of a few benzoate esters but required the use of 5.0 mol % catalyst. Aldehydes could also be converted into the corresponding 1,1-diesters (acylals) under the reaction conditions. Iron(III) tosylate is an inexpensive, and easy to handle, commercially available catalyst.


Synthesis Of Oligosaccharide Mimetics By The Desulfurative Rearrangement Of Allylic Disulfides And Stereoelectronic Influence Of C-O Bonds On C- And O-Glycosylation, Myriame Moume-Pymbock 2012 Wayne State University

Synthesis Of Oligosaccharide Mimetics By The Desulfurative Rearrangement Of Allylic Disulfides And Stereoelectronic Influence Of C-O Bonds On C- And O-Glycosylation, Myriame Moume-Pymbock

Wayne State University Dissertations

This dissertation focuses on two different problems. The first part of this manuscript presents the application of a novel methodology to access the synthesis of oligosaccharide mimetics while the second part focuses on the study of the stereoelectronic effects of proximal C-O bonds in C- and O-glycosylation reactions.

The first chapter provides a brief overview of the important roles that oligosaccharides and glycoconjugates play in biological processes and sets out the major advances that have been made in the past few decades in the synthesis of such complex structures while bringing out the ongoing challenges and the limitations that impede ...


Luminescent Nitrogen And Sulfure Adducts Of Cui Disubstituted Piperazine Complexes, Jason P. Safko 2012 College of William & Mary - Arts & Sciences

Luminescent Nitrogen And Sulfure Adducts Of Cui Disubstituted Piperazine Complexes, Jason P. Safko

Dissertations, Theses, and Masters Projects

No abstract provided.


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