Index Catalog // ScholarsArchive@OSU

A Pyrone Diels–Alder Approach to Substituted Indoles and Carbazoles and the Synthesis of New Ropinirole Analogues

Creator:: Points, Gary L., III
Abstract:: Aromatic heterocycles are core structural motifs in natural products, pharmaceuticals and biological polymers. Indoles, in particular, represent a significant subclass of aromatic heterocycles, both in terms of sheer numbers, but also in biological and pharmaceutical relevance. As such, new methodologies for the synthesis of indoles represent an important and continually...
Resource Type:: Dissertation

Total Synthesis of Aspidosperma Alkaloids Leuconoxine, Melodinine E and Mersicarpine and Synthetic Studies directed toward the Iboga Alkaloid Ibogaine: Progress directed toward the dimeric Cephalotaxus Alkaloid Cephalancetine C

Creator:: Kim, GilSoo
Abstract:: The first part of this manuscript is about the total synthesis of the aspidosperma alkaloids leuconoxine, melodinine E and mersicarpine. Our synthetic strategy used a radical translocation-conjugate addition cascade to construct the core of the natural product. Specifically, a vinyl radical was generated from the homolysis of the C–I bond...
Resource Type:: Dissertation

Stereocontrolled Synthesis of Allenes by Eliminative Cross-Coupling of Carbenoids

Creator:: Cao, Yang
Abstract:: The bimolecular reaction of two carbenoid species resulting in the formation of a carbon-carbon double bond (pi-system), referred to herein as carbenoid eliminative cross-coupling (CEXC), involves a series of three fundamental steps: (i) ate-complex formation (transmetalation), (ii) 1,2-metalate rearrangement, and (iii) beta-elimination. All three steps are stereospecific and so the...
Resource Type:: Dissertation

Development and Application of Mass Spectrometry-driven Methods for the Detection and Characterization of Biomolecular Signatures of Diseases

Creator:: Zandkarimi, Fereshteh
Abstract:: State-of-the-art, high-resolution mass spectrometry techniques for acquisition of metabolomic and lipidomic data coupled with advanced computational methods provide new opportunities for interpreting large and complex datasets and comprehending the underlying biological processes of diseases. Both metabolomics and lipidomics strive to obtain comprehensive analyses of small molecules, i.e., metabolites and lipids,...
Resource Type:: Dissertation

Removal of Radioactive Strontium, Iodine, and Uranium from Contaminated Groundwater : Sorption Processes and Properties

Creator:: Leonard, Mary E.
Abstract:: Iodine-129 is a key risk driver at sites where nuclear materials have been fabricated or processed, and it is a predominant isotope of concern in long-term waste storage strategies. I-129 exists primarily as iodate in the subsurface at the Hanford Site in south-central Washington State. Between 15 and 40% of...
Resource Type:: Dissertation

Scaffold reactivity and large scale Synthesis of organocatalyzed Yamada-Otani Condensation product and investigation of the synthesis and properties of axially chiral 8,8'-biquinolyls and 8-(naphtha-1-yl)quinolines

Creator:: Banerjee, Somdev
Abstract:: In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a...
Resource Type:: Dissertation

Stereospecific Synthesis of Stereotriad Motifs and Alkenes Using Enantioenriched sp³-Hybridized Carbenoids

Creator:: Xun, Sun
Abstract:: Enantioenriched sp³-hybridized carbenoid reagents CR1R2MX (X = nucleofuge, M = electrofuge) of different types were investigated for the synthesis of polysubstituted alkyl chains by iterative stereospecific reagent-controlled homologation (StReCH) and for the stereospecific connective synthesis of alkenes by eliminative cross-coupling. In the first part, putative enantioenriched α-chloroalkyllithiums (CHRLiCl) were employed...
Resource Type:: Dissertation

Chain extension of boronic esters with stereo- and regio-defined lithiated oxiranes

Creator:: Alwedi, Embarek
Abstract:: The stereospecific reagent-controlled homologation (StReCH) of boronic esters with putative lithiooxiranes generated in situ from appropriate precursors via sulfoxide-lithium exchange, tin-lithium exchange, and direct lithiation is described with an emphasis on the first lithiation technique which allows for the regio- and stereo-specific generation of all types of lithiooxirane isomer. Transient...
Resource Type:: Dissertation

Analysis of the mechanism of sulfoxide-lithium exchange and the reactive intermediate in stereospecific reagent-controlled homologation (StReCH)

Creator:: Hoyt, Amanda
Abstract:: The stereospecific reagent-controlled homologation (StReCH) of boronic esters with enantioenriched carbenoid species generated in situ by the addition of organolithium initiators to stereodefined α-chloroalkyl aryl sulfoxides was previously reported. The reaction of an organolithium with an α-chloroalkyl aryl sulfoxide ostensibly generates an α-chloroalkyllithium via sulfoxide-lithium exchange; however, the true nature...
Resource Type:: Masters Thesis

Himeradine A : synthetic efforts towards himeradine A and related natural products, a Michael reaction focused approach

Creator:: Collett, Nathan D.
Abstract:: Lycopodium alkaloids have generated enormous amounts of interest from the scientific community, both as synthetic targets and for their medicinal properties. Herein is described work towards a unifying approach to large segments of the Lycopodium family. An organocatalyzed intramolecular heteroatom Michael reaction method, for the construction of piperidine and piperizine...
Resource Type:: Dissertation

Synthesis and catalytic applications of derivatives of 7,7'-dihydroxy-8,8'-biquinolyl (azaBINOL)

Creator:: Wang, Chao
Abstract:: The synthesis of axially chiral polyfunctional derivatives of 8,8'-biquinolyl was explored and the catalytic action of appropriate derivative types investigated in three separate processes: (1) the silylcyanation of carbonyl groups and imines, (2) alkylation of a glycine Schiff-base via phase transfer-catalysis, and (3) direct amide bond formation from simple amines...
Resource Type:: Dissertation

Mass spectrometric studies on peptides and proteins : conformations of Escherichia coli Thioredoxin and its alkylated adducts studied by hydrogen/deuterium exchange and HPLC-electrospray ionization mass spectrometry

Creator:: Kim, Moo-young
Abstract:: E. coli thioredoxin (TRX) was modified by the episulfonium ion derived from S-(2-chloroethyl)glutathione (CEG) or S-(2-chloroethyl)cysteine (CEC). The alkylation site was located at Cys-32, which was confirmed by tandem mass spectrometry. Two forms of native TRX, Oxi- and Red-TRX, and two modified TRXs, GS- and Cys-TRX, were examined by hydrogen/deuterium...
Resource Type:: Dissertation

Studies on naphthyridinomycin biosynthesis

Creator:: He, Weixuan
Resource Type:: Dissertation

Studies toward the total synthesis of sanglifehrin A

Creator:: Suttisintong, Khomson
Abstract:: Studies toward synthesis of subunits of sanglifehrin A, an immunosuppressant featuring a highly substituted [5,5]-spirolactam moiety as well as a 22-membered macrocycle are described. The macrolactone contains a peptidic backbone characterized by an unusual [beta]-substituted (S)-piperazic acid and (S)-m-hydroxyphenylalanine units. These studies resulted in the synthesis of advanced intermediate 358...
Resource Type:: Dissertation

Proteomic approach to the analysis of DNA-binding proteins using mass spectrometry

Creator:: Stapels, Martha Degen
Abstract:: In proteomic studies, separate experimental protocols have been necessary to identify proteins, determine their function, and predict their three-dimensional structure. In this study, a function-based separation of proteins was conceived to fractionate proteins prior to enzymatic digestion. In the initial demonstration of this technique, a DNA substrate was used to...
Resource Type:: Dissertation

Synthesis of furanoeremophilane sesquiterpenoids

Creator:: Shanmugham, Meenakshi Sundaram
Abstract:: Two approaches to the tricyclic core of the furanoeremophilane sesquiterpenoids are described. The first approach entails a projected Diels-Alder/retro Diels-Alder reaction of an acetylenic oxazole 64. Construction of the pivotal aldehyde 67 commenced from ketone 68. The acetyenic moiety was then introduced via a Felkin-Ahn addition of lithiopropyne to aldehyde...
Resource Type:: Dissertation

Part I: Synthesis and evaluation of synosutine as an inhibitor of serotonin, norepinephrine, and dopamine transporters Part II: Asymmetric approach to the tetracyclic core of neomangicol A

Creator:: Juniku, Rajan B.
Abstract:: Part I: Racemic and asymmetric syntheses of a new substance with prospective antidepressant properties were achieved. In vitro assays with synthetic racemates (±)-25 and (±)-26 suggested that the former is a relatively selective inhibitor of serotonin transporter whereas the latter is a more balanced inhibitor of both serotonin and norepinephrine...
Resource Type:: Dissertation

Stereoselective synthesis & application of enantioenriched main group α-haloalkyl organometal reagents

Creator:: Emerson, Christopher R.
Abstract:: Sulfoxide-ligand exchange (SLE) and asymmetric halogen-metal exchange (AHME) processes were separately examined for the enantioselective synthesis of functionalized alpha-haloalkylmetal (carbenoid) reagents. Carbenoids derived from SLE were used to effect stereospecific reagent-controlled homologation (StReCH) of boronic esters and those generated via AHME were engaged in Darzens-type chemistry with aldehydes. Abstract for...
Resource Type:: Dissertation

Aryl acetylene substituent effects : the synthesis and application of biaryls

Creator:: Naffziger, Michael R.
Abstract:: The work described herein details the synthesis and application of biphenyls that probe the effects of hydrogen, Cl / Br, and methyl substituents on the aryl ring of the terminal acetylenic carbon. From this work, we successfully developed the rapid synthesis of phenyl acetylenes in 3-4 steps from inexpensive commercially...
Resource Type:: Masters Thesis

Studies toward the total synthesis of azaspiracid-1

Creator:: Kuiper, Damien L.
Abstract:: Azaspiracid has generated an enormous amount of scientific interest in the fourteen years since its initial discovery. The structure contains a 6,5,6 bis-spiroketal, a [3.3.1] bicyclic ketal and a 6,5-spiroaminal linkage as key moieties. With 9 rings, 20 stereocenters and three alkenes, the azaspiracid immediately attracted the interest of the...
Resource Type:: Dissertation

Development of organocatalyzed, intramolecular heteroatom Michael addition and application towards alkaloid synthesis

Creator:: Carlson, Erik
Abstract:: Effective methods for the enantiopure formation of substituted piperidine rings are significantly important due to their presence in alkaloid products. A valuable method to form these ring systems would be via an intramolecular heteroatom Michael addition from the corresponding enone or enal. Described herein is a methodolgy that has been...
Resource Type:: Masters Thesis

Catalytic desymmetrization of D₂d̳-symmertic proprochiral tetrasubstituted biphenyl compounds: a novel approach to the synthesis of axially chiral C₂-symmetric molecules

Creator:: Gunderson, Jeremey Tyson
Abstract:: Many D2d-symmetric 2,2',6,6'-tetrasubstituted biphenyls are readily prepared via net oxidative dimerization of appropriate 1,3-disubstituted benzenes. Conversion of such proprochiral compounds to useful C2-symmetric chiral biphenyls requires formal replacement of two substituents on opposing aryl ring units with alternate groups. This under exploited desymmetrization tactic has been demonstrated for the generation...
Resource Type:: Masters Thesis

Atropisomeric 8,8'-biquinolyl derivatives : synthesis, properties and applications

Creator:: Milicevic, Selena D.
Abstract:: 7,7'-Dihydroxy-8,8'-biquinolyl (azaBINOL) was prepared from 7-hydroxyquinoline via N,N-dimethyl O-quinol-7-yl carbamate by directed ortho-metallation followed by FeCl₃-mediated oxidative coupling of the 8-lithioquinoline intermediate. Saponification of the resulting dicarbamate provided crystalline (±)-azaBINOL in 56% overall yield. 6,6'-Bis(dimethylaminocarbonyl)-7,7'-dihydroxy-8,8´-biquinolyl was prepared from the same dicarbamate by a double anionic-Fries rearrangement in 43% yield. 7,7'-Bis(diethylamino-carbonyloxy)-6,6'-diiodo-8,8´-biquinolyl...
Resource Type:: Dissertation

Graphite intercalation compounds containing fluoroanions

Creator:: Katinonkul, Watcharee
Abstract:: New chemical synthesis strategies have been investigated for the preparation of acceptor-type graphite intercalation compounds (GIC's) with fluoroanions in order to obtain new materials and to develop a better understanding of the synthetic approaches and properties of the products. New GIC's containing borate chelate anion such as bis(oxalato)borate, CxB[OC(O)C(O)O]₂•δF, are...
Resource Type:: Dissertation

Studies toward the synthesis of halichlorine and pinnaic acid

Creator:: Korf, Eric A.
Abstract:: Three approaches toward the core of halichlorine and pinnaic acid are described. The first approach entails a racemic transannular nitrone-olefin [3+2] cycloaddition from nitrone 238. Construction of the nitrone 238 began with aldehyde 241. Another key feature in this route involved a ring-closing metathesis for the formation of a 14-membered...
Resource Type:: Dissertation

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