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Title: 9,11-secogorgosterol biosynthesis in gorgonians.
Creator: Kellman, Jaelle, Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: 9,11-secogorgosterol is a secondary metabolite from the gorgonian Pseudopterogorgia americana which acts as a chemical defense. The soft coral lives in a symbiotic association with unicellular algae known as zooxanthellae. A biosynthetic investigation, using in vivo and in vitro methods, has resulted in the identification of the metabolic precursor of 9,11-secogorgosterol as gorgosterol. This finding is significant as it indicates that the conversion of gorgosterol to 9,11-secogorgosterol is...
Show more9,11-secogorgosterol is a secondary metabolite from the gorgonian Pseudopterogorgia americana which acts as a chemical defense. The soft coral lives in a symbiotic association with unicellular algae known as zooxanthellae. A biosynthetic investigation, using in vivo and in vitro methods, has resulted in the identification of the metabolic precursor of 9,11-secogorgosterol as gorgosterol. This finding is significant as it indicates that the conversion of gorgosterol to 9,11-secogorgosterol is due to gorgonian metabolism. Since gorgosterol is known to be a product of zooxanthellae metabolism, this would be the first example of a defensive secondary metabolite being produced by two organisms living in symbiosis. A viable acetone powder has been generated from the crude cell-free extract and has demonstrated the efficient transformation of gorgosterol to 9, 11-secogorgosterol. This indicates possible future value as a synthetic tool for secosterol production.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15180
Subject Headings: Sterols--Synthesis, Alcyonacea
Format: Document (PDF)

Title: A New Approach to Sensitized Luminescence in Trivalent Lanthanide Coordination Polymers: From Fundamental Luminescence and Crystal Engineering Toward Sensing Applications.
Creator: Einkauf, Jeffrey D., De Lill, Daniel T., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Luminescent lanthanide containing coordination polymers and metal-organic frameworks hold great potential in many applications due to their distinctive spectroscopic properties. While the ability to design coordination polymers for specific functions is often mentioned as a major benefit bestowed upon these compounds, the lack of a meaningful understanding of the crystal engineering and luminescence in lanthanide coordination polymers remains a significant challenge toward functional design....
Show moreLuminescent lanthanide containing coordination polymers and metal-organic frameworks hold great potential in many applications due to their distinctive spectroscopic properties. While the ability to design coordination polymers for specific functions is often mentioned as a major benefit bestowed upon these compounds, the lack of a meaningful understanding of the crystal engineering and luminescence in lanthanide coordination polymers remains a significant challenge toward functional design. Currently, the study of luminescence attributed to these compounds is based on the antenna effect as derived from molecular systems, where organic antennae are used to facilitate lanthanide-centered luminescence. This molecular based approach does not take into account the unique features of extended network solids, particularly the formation of band structure. By comparing molecular and band-based approaches, it was determined that the band structure of the organic sensitizing linker needs to be considered when evaluating the luminescence of lanthanide coordination polymers. This new model, as well as work on the crystal engineering and sensor applications of these materials will be presented.
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Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004890, http://purl.flvc.org/fau/fd/FA00004890
Subject Headings: Rare earth metals., Lanthanide shift reagents., Organic compounds--Synthesis., Inorganic compounds--Synthesis., Metallic composites--Speciation., Polymeric composites., Organorare earth metal compounds., Nanostructured materials.
Format: Document (PDF)

Title: A STUDY ON THE CLINICAL RELEVANCE OF METALLOPROTEINASE INHIBITION.
Creator: Onwuha-Ekpete, Lillian, Fields, Gregg, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
Abstract/Description: The Metzincins are a superfamily of zinc-dependent endopeptidases associated with the regulation of the extracellular matrix (ECM). Their members include A Disintegrin and Metalloproteinase with Thrombospondin Motifs (ADAMTSs), A Disintegrin and Metalloproteinases (ADAMs), and the matrix metalloproteinases (MMPs). Metzincins exhibit diverse functions associated with both physiological and pathological states that include the proteolytic degradation of the ECM, regulation of various growth...
Show moreThe Metzincins are a superfamily of zinc-dependent endopeptidases associated with the regulation of the extracellular matrix (ECM). Their members include A Disintegrin and Metalloproteinase with Thrombospondin Motifs (ADAMTSs), A Disintegrin and Metalloproteinases (ADAMs), and the matrix metalloproteinases (MMPs). Metzincins exhibit diverse functions associated with both physiological and pathological states that include the proteolytic degradation of the ECM, regulation of various growth factors, cell surface receptors, and chemokines, and mediation of biological functions such as extravasation, survival, and proliferation. In pathological conditions such as cancer associated with chronic inflammation and multiple sclerosis associated with neurodegeneration, dysregulation of Metzincin activities are a hallmark of disease progression and severity. Hence, Metzincins are therapeutic targets for various disease states and research into optimal Metzincin inhibitor design is an ongoing exploit.
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Date Issued: 2020
PURL: http://purl.flvc.org/fau/fd/FA00013615
Subject Headings: Matrix Metalloproteinase 2, Matrix Metalloproteinase 9, T cells, Immunology
Format: Document (PDF)

Title: Aggregation Inhibition and Detection of Alzheimer’s Amyloidogenic and Oligomeric Peptides.
Creator: Elbassal, Esmail A. E., Du, Deguo, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Protein aggregation, oligomer and fibril formation is one of the dominant characteristics in the pathogenesis of a number of neurodegenerative diseases, such as Alzheimer’s disease (AD). Inhibition of toxic oligomer and fibril formation is one of the approaches to find potential drug candidates for AD. Additionally, early diagnosis of these amyloid species can provide mechanistic understanding of protein aggregation and thus can pave the way for preventing the onset of AD. The aim of this...
Show moreProtein aggregation, oligomer and fibril formation is one of the dominant characteristics in the pathogenesis of a number of neurodegenerative diseases, such as Alzheimer’s disease (AD). Inhibition of toxic oligomer and fibril formation is one of the approaches to find potential drug candidates for AD. Additionally, early diagnosis of these amyloid species can provide mechanistic understanding of protein aggregation and thus can pave the way for preventing the onset of AD. The aim of this dissertation was 1) to explore the effects of charged cholesterol derivatives on the aggregation kinetic behavior of Amyloid-β40 (Aβ40), 2) to probe Aβ40 oligomer and amyloid formation in vitro using gold nanoparticles (AuNPs), and 3) to monitor the kinetic effect of various natural product molecules on Aβ40 aggregation in vitro. In the first chapter, a general introduction about AD as an amyloidogenic disease, amyloid cascade hypothesis, and the manipulation of Aβ peptides aggregation kinetics using different approaches was presented. In the second chapter, we studied the effects of oppositely charged cholesterol derivatives on the aggregation kinetics of Aβ. In the third chapter, we developed a gold nanoparticles (AuNPs) assay to probe Aβ40 oligomers and amyloid formation. In chapter IV, we monitored the effects of various small molecules on the aggregation kinetics of Aβ40. In chapter V, we discussed the methods and experimental details.
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Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00013009
Subject Headings: Alzheimer's disease, Amyloid beta-protein, Oligomers, Protein Aggregates, Neurodegenerative Diseases
Format: Document (PDF)

$Aggregation kinetics of A\U+fffd\ peptides and the inhibition effects of small molecules on A\U+fffd\ peptide aggregation$

Title: Aggregation kinetics of A\U+fffd\ peptides and the inhibition effects of small molecules on A\U+fffd\ peptide aggregation.
Creator: Hijazi, Ahmad Alex., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: The pathology of Alzheimer's disease (AD) remains elusive. Competing evidence links amylois \U+fffd\-peptide (A\U+fffd\) amyloid formation to the phenotype of AD (1). The mechanism of amyloid fibril formation has been an ongoing investigation for many years. A\U+fffd\10-23 peptide, a fragment of A\U+fffd\1-42 peptide, contained crucial hydrophobic core residues (2). In this study, an investigation was launched to study the aggreagation process of A\U+fffd\1023 peptide and its ability to form...
Show moreThe pathology of Alzheimer's disease (AD) remains elusive. Competing evidence links amylois \U+fffd\-peptide (A\U+fffd\) amyloid formation to the phenotype of AD (1). The mechanism of amyloid fibril formation has been an ongoing investigation for many years. A\U+fffd\10-23 peptide, a fragment of A\U+fffd\1-42 peptide, contained crucial hydrophobic core residues (2). In this study, an investigation was launched to study the aggreagation process of A\U+fffd\1023 peptide and its ability to form amyloid fibrils. Furthermore, the presence of its hydrophobic core showed importance for its ability to aggregate and form amyloid fibrils. Thereafter, the inhibition of A\U+fffd\1-42 peptide aggregation was studied by using pyrimidine-based compounds. A\U+fffd\1-42 peptides, known to be neurotoxic, aggregate to form amyloid fibrils (3). This investigation may provide insight into the development of novel small molecular candidates to treat AD.
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Date Issued: 2012
PURL: http://purl.flvc.org/FAU/3358550
Subject Headings: Amyloid beta-protein, Proteins, Metabolism, Disorders, Prions, Alzheimer's disease
Format: Document (PDF)

Title: ALLENYL ESTER BUILDING BLOCKS: THEIR APPLICATION TO THE SYNTHESIS OF BRIDGED BICYCLIC COMPOUNDS AND UTILITY AS PRENUCLEOPHILES IN THE DIASTEREOSELECTIVE FORMATION OF ALL-CARBON QUATERNARY ALDOL PRODUCTS.
Creator: Maki, Samantha, Lepore, Salvatore, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
Abstract/Description: The present dissertation will be largely focused on the synthesis of various [3.2.1] bridged bicycles using allenyl esters. Chapter one will present the importance of various [3.n.1] bridged bicycles in medicinal chemistry. A three-step synthetic route will then be described on how to produce a small library of [3.n.1] bridged bicycles using allenyl esters in an annulation reaction. The [3.n.1] bicyclic diketones can then undergo Grob fragmentation to deliver highly functionalized medium...
Show moreThe present dissertation will be largely focused on the synthesis of various [3.2.1] bridged bicycles using allenyl esters. Chapter one will present the importance of various [3.n.1] bridged bicycles in medicinal chemistry. A three-step synthetic route will then be described on how to produce a small library of [3.n.1] bridged bicycles using allenyl esters in an annulation reaction. The [3.n.1] bicyclic diketones can then undergo Grob fragmentation to deliver highly functionalized medium sized rings. Studies towards the total synthesis of vitisinol D, a highly functionalized [3.2.1] bridged bicycle will be discussed. In chapter two, synthesis knowledge gleamed from chapter one will be used to create a model route to form simplified versions of vitisinol D, called resveramorphs. These resveramorphs are structurally similar to resveratrol but possess rigid three-dimensional configuration desired in drug design. The synthetic route to create a variety of resveramorphs will be reported. The sub-nanomolar results of various resveramorph compounds in a Drosophila melanogaster neural tissue model under oxidative stress will be reported. Chapter three will focus on the use of allenyl esters as prenucleophiles to produce triply diastereoselective β-hydroxy esters containing all carbon α-quaternary centers. The challenges in the opitmization of this novel reaction will be described. The relative stereochemistry of the β-hydroxy ester products will be presented using various techniques including X-ray crystallography, 1D NMR, 2D NMR, and force field calculations (MM2). A closed transition state mechanism will be proposed to describe the diastereoselectivity that is observed in the reaction. Additionally, a short indanone synthesis will be shown as a potential application for this novel reaction.
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Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013391
Subject Headings: Bicyclic compounds, Esters, Diastereoisomers
Format: Document (PDF)

Title: AMYLOIDOGENICITY OF THE PEPTIDE FRAGMENT IN MICROTUBULE BINDING REPEAT DOMAIN OF TAU.
Creator: Islam, Majedul, Du, Deguo, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
Abstract/Description: Tau, a microtubule-associated protein, is involved in more than 20 different tauopathic disorders characterized by aberrant intracellular aggregation of tau in the brain. However, it is still unclear how this highly soluble tau protein aggregates inside the brain. Thus, understanding the mechanistic details of tau aggregation is critical for unraveling the underlying pathology of tauopathies and developing effective strategies to inhibit tau aggregation. Herein, we investigated the...
Show moreTau, a microtubule-associated protein, is involved in more than 20 different tauopathic disorders characterized by aberrant intracellular aggregation of tau in the brain. However, it is still unclear how this highly soluble tau protein aggregates inside the brain. Thus, understanding the mechanistic details of tau aggregation is critical for unraveling the underlying pathology of tauopathies and developing effective strategies to inhibit tau aggregation. Herein, we investigated the aggregation of a novel 20-residue model peptide, tau₂₉₈₋₃₁₇, derived from the key microtubule-binding domain of the full sequence tau. Our study demonstrates that tau₂₉₈₋₃₁₇ highly mimics full-length tau's physical and aggregation properties. The fibrillation of the peptide is strongly dependent on external factors. The presence of polyanionic heparin (Hep) significantly promotes the aggregation of this peptide to form amyloid fibrils. The Hep-induced aggregation is sensitive to the ionic strength of the solution, suggesting an important role of electrostatic interactions in the mechanism of Hep-mediated aggregation. In addition, two positively charged polysaccharides, chitosan (CHT) and its quaternary derivative N-trimethyl chitosan (TMC), effectively inhibit Hep-induced aggregation of tau₂₉₈₋₃₁₇ in a concentration-dependent manner. Attractive electrostatic interactions between the positively charged moieties in CHT/TMC and the negatively charged residues of Hep play a critical role in inhibiting Hep–peptide interactions and suppressing peptide aggregation.
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Date Issued: 2023
PURL: http://purl.flvc.org/fau/fd/FA00014211
Subject Headings: tau Proteins, Tauopathies, Amyloidogenic Proteins
Format: Document (PDF)

Title: ANALYSIS OF COMPUTATIONAL METHODS FOR THE ELECTRONIC TRANSITIONS OF ISOBUTENE.
Creator: Garbaran, Avinash, Snyder, Patricia, Florida Atlantic University, Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
Abstract/Description: To help determine the ideal computational method for the analysis of the π → π* region in ethylene, analysis of isobutene’s computational results versus previously obtained experimental results was performed. Several time-dependent DFT calculations were performed, with eleven functionals being paired with twelve basis sets. The LSDA functional with the cc-pVQZ basis set came the closest to experimental results, with calculated transitions at 50502 cm-1, 56484 cm-1, and 59594 cm-1 compared to...
Show moreTo help determine the ideal computational method for the analysis of the π → π* region in ethylene, analysis of isobutene’s computational results versus previously obtained experimental results was performed. Several time-dependent DFT calculations were performed, with eleven functionals being paired with twelve basis sets. The LSDA functional with the cc-pVQZ basis set came the closest to experimental results, with calculated transitions at 50502 cm-1, 56484 cm-1, and 59594 cm-1 compared to experimental transition at 49875 cm-1, 55277 cm-1, and 59944 cm-1 (difference of 1.258%, 2.184%, and 0.583%, respectively). With BVP86 cc-pVQZ, calculated transitions were at 51195 cm-1, 56541 cm-1, and 59984 cm-1 (difference of 2.647%, 2.288%, and 0.067%, respectively). While LSDA cc-pVQZ was the best, it was notable how close second place came, thus the inclusion of BVP86 cc-pVQZ.
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Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013373
Subject Headings: Density functionals, Computational Chemistry, Ethylene--Analysis
Format: Document (PDF)

Title: ATOMIC MOLECULAR THEORY: A PROGRAMMED TEXT USED IN THE TEACHING OF BASIC ATOMIC AND MOLECULAR ORBITAL THEORY IN A HIGH SCHOOL PROGRAM OF CHEMISTRY.
Creator: SEVERANCE, H. WILSON, JR., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: This program was developed from necessity found in the teaching of molecular geometry to high school chemistry classes. Recent journals and textbooks were consulted in evaluation of the modern emphasis on instruction in molecular geometry at the high school level, and the topic was then developed fully for use in the chemistry course at the Ransom School, serving as a base for other instructional units. A self-teaching concept was employed in this manual in order that the student might...
Show moreThis program was developed from necessity found in the teaching of molecular geometry to high school chemistry classes. Recent journals and textbooks were consulted in evaluation of the modern emphasis on instruction in molecular geometry at the high school level, and the topic was then developed fully for use in the chemistry course at the Ransom School, serving as a base for other instructional units. A self-teaching concept was employed in this manual in order that the student might proceed at his own pace and according to his own needs. The principal intention was to familiarize the student with the shapes and configurations of various molecules and thereby to give him greater insight into the physical picture of molecular interaction in chemical reaction.
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Date Issued: 1974
PURL: http://purl.flvc.org/fcla/dt/13656
Subject Headings: Molecular orbitals--Study and teaching (Secondary), Chemistry--Study and teaching (Secondary)--Programmed instruction, Atomic theory--Study and teaching (Secondary)
Format: Document (PDF)

Title: Bioactive terpene production associated with Caribbean gorgonians from the genera Pseudopterogorgia and Eunicea: Discovery of a sustainable production method.
Creator: Newberger, Nealie C., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Research directed toward renewable, non-destructive sources of bioactive marine derived compounds, is becoming more important everyday. Marine soft corals known as sea whips are a prolific source of such biologically active compounds. One particular organism, Eunicea fusca, possesses diterpene arabinose glycosides with potent antiinflammatory activity that rival the industry standard indomethicin. Fuscocide B is known to inhibit phorbol myristate acetate (PMA)-induced ear edema in murine...
Show moreResearch directed toward renewable, non-destructive sources of bioactive marine derived compounds, is becoming more important everyday. Marine soft corals known as sea whips are a prolific source of such biologically active compounds. One particular organism, Eunicea fusca, possesses diterpene arabinose glycosides with potent antiinflammatory activity that rival the industry standard indomethicin. Fuscocide B is known to inhibit phorbol myristate acetate (PMA)-induced ear edema in murine models, is a minor secondary metabolite and it is therefore difficult to acquire in large quantities. Alternatively, fuscol and eunicol, are known to have similar antiinflammatory activity and are major secondary metabolites which are structurally similar to fuscocide B and are also produced by E. fusca. We have found that fuscol and eunicol can be extracted from the holobiont, and Symbiodinium (Symbiodinium sp.) cells isolated from E. fusca. Similarly, diterpene glycosides, known as pseudopterosins, have been isolated from the the holobiont, and purified Symbiodinium of Pseudopterogorgia elisabethae. Pseudopterosins are also known to possess anti-inflammatory and analgesic properties superior to that of existing drugs. Since many chemically unique metabolites demonstrating bioactive properties have been introduced into pre-clinical and clinical trials I-III5 and the supply issue has been duly highlighted, it has become advantageous to determine the source of these compounds in each of the above mentioned species and determine if a renewable, non-destructive source can be maintained. Data has been presented suggesting that the actual source of the pseudopterosins is not the coral, but actually the dinoflagellate symbiont associated with Pseudopterogorgia elisabethae. Therefore, we have examined cryopreservation of the dinoflagellate symbionts, induction of terpene biosynthesis in the dinoflagellate symbionts, as well as various cell culture techniques in order to better understand the ecological role of terpene biosynthesis in the symbionts and the host corals. The data obtained in the following studies reveals a bacterial source for the production of bioactive secondary metabolites from Eunicea fusca and lends support to a possible bacterial producing trend in gorgonians.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/12224
Subject Headings: Biology, Oceanography, Chemistry, Biochemistry, Chemistry, Organic
Format: Document (PDF)

Title: The biosynthetic production of marine-derived anti-tumor ecteinascidins and the aquaculture of the marine tunicate Ecteinascidia turbinata.
Creator: Krenisky, Joann Mary, Florida Atlantic University, Kerr, Russell G., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: A family of tetrahydroisoquinoline alkaloids, the ecteinascidins, are a group of biologically active secondary metabolites produced by the marine tunicate Ecteinascidia turbinata. Ecteinascidins have shown in vivo anti-tumor activity against P388 lymphoma, B16 melanoma, M5076 ovarian sarcoma, Lewis lung carcinoma, and LX-1 human lung and MX-1 human mammary carcinoma xenografts in laboratory mice. Because ecteinascidins are produced in low yields, 1x10^-4%, supply for clinical development is a...
Show moreA family of tetrahydroisoquinoline alkaloids, the ecteinascidins, are a group of biologically active secondary metabolites produced by the marine tunicate Ecteinascidia turbinata. Ecteinascidins have shown in vivo anti-tumor activity against P388 lymphoma, B16 melanoma, M5076 ovarian sarcoma, Lewis lung carcinoma, and LX-1 human lung and MX-1 human mammary carcinoma xenografts in laboratory mice. Because ecteinascidins are produced in low yields, 1x10^-4%, supply for clinical development is a significant problem. The ultimate goal of this study is to develop an enzyme-based synthesis of the ecteinascidins. In this regard, the biosynthesis of these alkaloids has been investigated. Optimal conditions for in vitro ecteinascidin biosynthesis were found. The origin of the C22-C1 two-carbon unit was identified as pyruvate and the tyrosine and DOPA diketopiperazines were identified as key intermediates. Methods were developed for an in-the-sea aquaculture of the colonal marine ascidian Ecteinascidia turbinata.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15454
Subject Headings: Sea squirts, Tetrahydroisoquinolines, Alkaloids--Synthesis
Format: Document (PDF)

Title: Biosynthetic Studies of the Bryostatins, Anticancer Agents from the Marine Bryozoan Bugu/a neritina.
Creator: Lawry, Joseph, Kerr, Russell G., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: The bryostatins are a family of macrolide lactones isolated from the marine bryozoan Bugu/a neritina. Since its detection in 1968, bryostatin 1 has demonstrated remarkable anticancer, immunopotentiating, biomodulatory and radioprotective effects which result mainly from its ability to activate protein kinase C, a family of isozymes involved in cellular signal transduction. It is currently being tested in several phase I and phase II clinical trials as a potential anticancer drug for leukemia,...
Show moreThe bryostatins are a family of macrolide lactones isolated from the marine bryozoan Bugu/a neritina. Since its detection in 1968, bryostatin 1 has demonstrated remarkable anticancer, immunopotentiating, biomodulatory and radioprotective effects which result mainly from its ability to activate protein kinase C, a family of isozymes involved in cellular signal transduction. It is currently being tested in several phase I and phase II clinical trials as a potential anticancer drug for leukemia, melanoma and nephrotoma. A series of experiments was undertaken to elucidate the biosynthetic origins of bryostatin, using a fortified crude cell-free enzyme preparation and radiolabelled precursors. A regional characterization of Bugula neritina from Sicily, Italy and Daytona Beach, Florida is also described.
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Date Issued: 1997
PURL: http://purl.flvc.org/fau/fd/FA00000787
Subject Headings: Macrolide antibiotics, Bryozoa, Marine pharmacology
Format: Document (PDF)

Title: Carbohydrate Recognition of Bi-pyridine Bridged Peptide Receptor.
Creator: Johnson, Claudia A., Cudic, Predrag, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: A novel carbohydrate receptor based on the structure of the antibiotic polymxin B was synthesized. The receptor was a cyclic heptapeptide. which was bridged using 2, 2'-bi pyridine-5,5"- dicarboxylic acid. The association constants of the receptor and a variety of sugars were determined using UV /Vis and fluorescence spectroscopy and observed log K0 values are in the range from 3 .8 to 4.1 for the pentoses, logKa 3.3 to 3.8 for the hexoxes and 0 to 2.9 logKa values from 0-2.9 for...
Show moreA novel carbohydrate receptor based on the structure of the antibiotic polymxin B was synthesized. The receptor was a cyclic heptapeptide. which was bridged using 2, 2'-bi pyridine-5,5"- dicarboxylic acid. The association constants of the receptor and a variety of sugars were determined using UV /Vis and fluorescence spectroscopy and observed log K0 values are in the range from 3 .8 to 4.1 for the pentoses, logKa 3.3 to 3.8 for the hexoxes and 0 to 2.9 logKa values from 0-2.9 for disaccharides and logKa of2.6 to 3.11 for the charged sugars. We demonstrated that polymixin based receptors are capable of binding various monosaccharide substrates in aqueous media, displaying structure selectivity with respect to monosaccharide ring size.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00000776
Subject Headings: Protein engineering, Neuropeptides--Receptors, Chemistry, Organic, Cellular recognition
Format: Document (PDF)

Title: Catalytic Asymmetric Isomerizations of Alkynes To Allenes And Their Diastereoselective Functionalization Facilitated By An Organomanganese Auxiliary.
Creator: Roy, Animesh, Lepore, Salvatore D., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: The present dissertation research is largely focused on the methods to synthesize highly substituted allene derivatives from alkynes in conjugation with carbonyl-containing functional groups. A key aspect of this research involves methylcyclopentadienylmanganese dicarbonyl (MMD), an inexpensive and air-stable organometallic auxiliary linked to alkynyl carbonyls via an η2-bond. This auxiliary influences bond formation to achieve enhanced stereoselectivity without itself undergoing any chemical...
Show moreThe present dissertation research is largely focused on the methods to synthesize highly substituted allene derivatives from alkynes in conjugation with carbonyl-containing functional groups. A key aspect of this research involves methylcyclopentadienylmanganese dicarbonyl (MMD), an inexpensive and air-stable organometallic auxiliary linked to alkynyl carbonyls via an η2-bond. This auxiliary influences bond formation to achieve enhanced stereoselectivity without itself undergoing any chemical transformation. Chapter 1 accounts various examples of such transition metal auxiliaries including MMD. Typically conjugated alkynyl carbonyls do not isomerize to thermodynamically less favored allenes. However, with the MMD auxiliary in place, alkynyl carbonyl compounds undergo facile 1,3-proton shifts in the presence of a mild base to produce allene isomers. Although allenyl aldehydes are important building blocks, we note that direct methods to prepare them nonracemically are not known. Chapter 2 describes the development of a new cinchonine-based phase transfer catalyst to access non-racemic allenyl aldehydes from MMD-complexed alkynyl aldehydes. With the manganese auxiliary in place, nonracemic allenyl aldehydes were obtained in a weakly basic biphasic reaction system via enantioselective protonation conditions. Chapter 3 describes the second use of the MMD auxiliary to direct nucleophilic addition reactions to allenyl aldehydes for the preparation of 2,3-allenols diastereoselectively. In the absence of the MMD auxiliary, nucleophilic reactions to the carbonyl group of axially chiral allenyl aldehydes is poorly diastereoselective, which is a long-standing problem. We observed that, in addition to leading to non-racemic allenyl aldehydes, the MMD auxiliary could also be used to improve diastereoselectivity in carbonyl additions due to its proximal position on the 2,3-bond of the allenyl aldehyde. Chapter 4 describes the use of allenyl esters as metathesis quenching agents. It was observed that the addition of an allenyl ester after a metathesis reaction was complete; facilitate the removal of most ruthenium metal impurities using simple silica chromatographic purification.
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Date Issued: 2017
PURL: http://purl.flvc.org/fau/fd/FA00004918
Subject Headings: Transition metal catalysts., Stereochemistry., Chemistry, Organic., Chemistry, Physical and theoretical., Asymmetric synthesis.
Format: Document (PDF)

Title: Cell-surface glycan-lectin interactions for biomedical applications.
Creator: Rodriguez Benavente, Maria Carolina, Lepore, Salvatore D., Cudic, Predrag, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Carbohydrate recognition is one of the most sophisticated recognition processes in biological systems, mediating many important aspects of cell-cell recognition, such as inflammation, cell differentiation, and metastasis. Consequently, lectin-glycan interactions have been intensively studied in order to mimic their actions for potential bioanalytical and biomedical applications. Galectins, a class of ß-galactoside-specific animal lectins, have been strongly implicated in inflammation and...
Show moreCarbohydrate recognition is one of the most sophisticated recognition processes in biological systems, mediating many important aspects of cell-cell recognition, such as inflammation, cell differentiation, and metastasis. Consequently, lectin-glycan interactions have been intensively studied in order to mimic their actions for potential bioanalytical and biomedical applications. Galectins, a class of ß-galactoside-specific animal lectins, have been strongly implicated in inflammation and cancer. Galectin-3 is involved in carbohydrate-mediated metastatic cell heterotypic and homotypic adhesion via interaction with Thomsen-Friedenreich (TF) antigen on cancer-associated MUC1. However, the precise mechanism by which galectin-3 recognizes TF antigen is poorly understood. Our thermodynamic studies have shown that the presentation of the carbohydrate ligand by MUC1-based peptide scaffolds can have a major impact on recognition, and may facilitate the design of more potent and specific galectin-3 inhibitors that can be used as novel chemical tools in dissecting the precise role of galectin-3 in cancer and inflammatory diseases. Another lectin, odorranalectin (OL), has been recently identified from Odorrana grahami skin secretions as the smallest cyclic peptide lectin, has a particular selectivity for L-fucose and very low toxicity and immunogenicity, rendering OL an excellent candidate for drug delivery to targeted sites, such as: (1) tumor-associated fucosylated antigens implicated in the pathogenesis of several cancers, for overcoming the nonspecificity of most anticancer agents; (2) the olfactory epithelium of nasal mucosa for enhanced delivery of peptide-based drugs to the brain.
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Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00004405
Subject Headings: Biopharmaceutics, Carbohydrates -- Therapeutic use, Cell differentiation, Drug delivery systems, Glycoproteins, Glycoslation, Mice as laboratory animals, Peptides -- Derivatives, Pharmaceutical biotechnology
Format: Document (PDF)

Title: Characterization of Disulfide Constrained Natural Peptides.
Creator: Hoggard, Mickelene F., Cudic, Mare, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: The use of peptide drugs has gained popularity recently. Peptides are attractive drug targets due to their high specificity and potency towards their biological targets. A drawback for peptide drugs is a lack of stability for oral delivery. Two classes of disulfide-rich peptides, conotoxins and cyclotides, have been shown to have higher stability than linear peptides thanks to their disulfide connectivity. Conotoxins are present in the venom of cone snails, a carnivorous marine mollusk that...
Show moreThe use of peptide drugs has gained popularity recently. Peptides are attractive drug targets due to their high specificity and potency towards their biological targets. A drawback for peptide drugs is a lack of stability for oral delivery. Two classes of disulfide-rich peptides, conotoxins and cyclotides, have been shown to have higher stability than linear peptides thanks to their disulfide connectivity. Conotoxins are present in the venom of cone snails, a carnivorous marine mollusk that preys upon fish, worms, or other mollusks. Conotoxins are promising drugs leads with great prospects in the treatment of diseases and disorders such as chronic pain, multiple sclerosis and Parkinson’s and Alzheimer’s diseases. Cyclotides, which are cyclic cysteine knot containing peptides, isolated from the Violaceae (violet), Rubiaceae (coffee), and Cucurbitaceae (cucurbit) families and they have a wide range of biological activities, such as anti-HIV, uterotonic, and antimicrobial. P-superfamily framework IX conotoxins (C-C- C-CXC- C) contain the same cysteine framework, homologous sequences, and similar 3D structures to cyclotides. The knot containing conotoxins have been identified in several Conus species, but this work focuses on those from Conus brunneus, Conus purpurascens, and Conus gloriamaris. The cysteine knot motif of cyclotides and P-superfamily conotoxins is characterized by a cyclic backbone and six-conserved cysteine residues that form the three-disulfide bridges of the “knot”. This motif provides cyclotides and conotoxins with superior stability against thermal, chemical, and enzymatic degradation; marking them as potential frameworks for peptide drug delivery. Presented are details on the isolation of conotoxins and cyclotides, from Viola tricolor, and the characterization of their activity in the well-characterized Drosophila melanogaster giant fiber system (GFS) neuronal circuit, which contains GAP, acetylcholine, and glutamate synapses. The transcriptomes of two Conus brunneus specimens were assembled and mined for P-superfamily framework IX conotoxins. Eleven mature P-superfamily framework IX conotoxins were identified in the crude venom.
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Date Issued: 2018
PURL: http://purl.flvc.org/fau/fd/FA00005955
Subject Headings: Peptide drugs, Cyclotides, Conotoxins
Format: Document (PDF)

Title: Chemical Studies of Caribbean Marine Organisms.
Creator: Vansach, Tifanie, West, Lyndon M., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: The projects described in this dissertation concentrated on investigating Caribbean species for qualitative and quantitative chemical differences. Chapter one includes a brief update on the status of natural products as drugs, a discussion of the biodiversity of Caribbean marine organisms as well as a discussion about the chemistry of algae and sponges. In chapter two, an experiment to test for possible effects of warmer, more acidic water and how that will impact coral reef organisms was...
Show moreThe projects described in this dissertation concentrated on investigating Caribbean species for qualitative and quantitative chemical differences. Chapter one includes a brief update on the status of natural products as drugs, a discussion of the biodiversity of Caribbean marine organisms as well as a discussion about the chemistry of algae and sponges. In chapter two, an experiment to test for possible effects of warmer, more acidic water and how that will impact coral reef organisms was conducted. Six common Caribbean coral reef sponge species were grown in seawater for 24 days ranging from values experienced at summer-maxima (temperature = 28 ºC; pH = 8.1) to those predicted for the year 2100 (T = 31 ºC; pH = 7.8). For each species, attachment rates, growth, and survival were similar between temperature and pH levels. Only two metabolite concentrations varied significantly between treatments but were similar to baseline levels. In chapter three, a chemical survey of Florida Keys algae was performed using MeOH extraction and HP-20 SPE with varying Me2CO:H2O solutions. 1H NMR spectra were collected for each fraction and analyzed for interesting signals. A Laurencia sp. was extracted and found to contain the known compound isodactylyne (61) with the structure determined using spectroscopic analyses. In chapter four, a Laurencia obtusa specimen was investigated to determine the compound causing oxygenated signals between 4.50 – 4.80 ppm in the 1H NMR spectra observed in chapter three. A large scale extraction and fractionation was performed and the compound was determined to be 1-O-palmitoyl-2-O-myristoyl-3-O-(6-sulfo-α- D-quinovo-pyranosyl)-glycerol (63). In chapter five, the isolation and structural elucidation of a new compound, furocaespitanenone (64) and two known compounds (10R)- and (10S)-10-O-methylfurocaespitanelactol 65 and 66, from a Laurencia sp. collected off of the Florida Keys using MeOH extraction and HP-20 column chromatography is described. A potential biosynthesis of 64 from furocaepsitane (68) is proposed.
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Date Issued: 2019
PURL: http://purl.flvc.org/fau/fd/FA00013274
Subject Headings: Marine organisms, Caribbean, Algae--chemistry, Sponges--Caribbean Sea, Chemistry
Format: Document (PDF)

Title: The chemistry of Briareum asbestinum.
Creator: Rondeau, Melody D., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Briareum asbestinum, a soft coral, is a rich source of diterpenoid natural products. The secondary metabolites of B. asbestinum fall into four classes : asbestinins, briarellins, briareolate esters, and briaranes. Briareolate esters have been shown to possess biological activity and were previously only reported from Tobago. Our group recently isolated briareolate esters from a specimen collected off the coast of Boca Raton, Florida. To determine whether location has an impact on the...
Show moreBriareum asbestinum, a soft coral, is a rich source of diterpenoid natural products. The secondary metabolites of B. asbestinum fall into four classes : asbestinins, briarellins, briareolate esters, and briaranes. Briareolate esters have been shown to possess biological activity and were previously only reported from Tobago. Our group recently isolated briareolate esters from a specimen collected off the coast of Boca Raton, Florida. To determine whether location has an impact on the chemistry produced by the organism, a method to discern between chemotypes was sought. Several techniques including thin layer chromatography (TLC), high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), and sclerite analysis were employed, with NMR being the most successful method. By utilizing both 1H and COSY NMR experiments, it is possible to differentiate between the chemotypes of B. asbestinum. Application of this method allowed analysis of chemical variability with respect to location.
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Date Issued: 2012
PURL: http://purl.flvc.org/FAU/3355882
Subject Headings: Heterocyclic compounds, Synthesis, Coral reef ecology, Marine organisms, Environmental aspects, Biochemical markers
Format: Document (PDF)

Title: Comparison of alkyl-bonded alumina-based stationary phases for peptide separation by high performance liquid chromatography.
Creator: Ramdial, Nirmala Debra-Ann, Florida Atlantic University, Haky, Jerome E., Department of Chemistry and Biochemistry, Charles E. Schmidt College of Science
Abstract/Description: The performance of several alkyl-bonded alumina-based stationary phases was evaluated by comparing the separation of synthetic octapeptide and polypeptide mixtures and tryptic digests of larger proteins. These phases were of differing pore diameter, alkyl chain length modification and particle shape and size. The separations were compared to standard silica phases. The narrow pore octadecyl bonded alumina phase outperformed the other alumina and silica phases in terms of separation efficiency...
Show moreThe performance of several alkyl-bonded alumina-based stationary phases was evaluated by comparing the separation of synthetic octapeptide and polypeptide mixtures and tryptic digests of larger proteins. These phases were of differing pore diameter, alkyl chain length modification and particle shape and size. The separations were compared to standard silica phases. The narrow pore octadecyl bonded alumina phase outperformed the other alumina and silica phases in terms of separation efficiency and mobile phase resistance. Superior performance is attributed to the enhanced solute mass transfer properties and the unique morphology of the microplatelet alumina particles. The mechanism of separation gradually changes with increasing size of the peptide.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14831
Subject Headings: Peptides--Separation, Liquid chromatography
Format: Document (PDF)

Title: Comparison of chemotaxonomic methods for the determination of periphyton community composition.
Creator: Browne, Jamie L., Charles E. Schmidt College of Science, Department of Chemistry and Biochemistry
Abstract/Description: Pigment-based chemotaxonomy uses relative amounts of photosynthetic pigments (biomarkers) within algae samples to determine the algal class composition of each sample. Chemotaxonomy has been applied successfully to phytoplankton communities, but its efficacy for periphyton has not yet been established. This study examined the ability of simultaneous linear equations (SLE), CHEMTAX, and the Bayesian Compositional Estimator (BCE) to determine algal class composition in Florida Everglades...
Show morePigment-based chemotaxonomy uses relative amounts of photosynthetic pigments (biomarkers) within algae samples to determine the algal class composition of each sample. Chemotaxonomy has been applied successfully to phytoplankton communities, but its efficacy for periphyton has not yet been established. This study examined the ability of simultaneous linear equations (SLE), CHEMTAX, and the Bayesian Compositional Estimator (BCE) to determine algal class composition in Florida Everglades periphyton. The methods were applied to artificial datasets, mixed lab cultures of known composition, and Everglades periphyton samples for which microscopic biovolume data was available. All methods were able to return accurate sample compositions for artificial data and mixed lab cultures. Correlation between pigment methods and microscopic results for natural periphyton samples was poor. SLE and CHEMTAX returned similar results for all samples while BCE performed less well.
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Date Issued: 2010
PURL: http://purl.flvc.org/FAU/2100582
Subject Headings: Water quality biological assessment, Periphyton, Water, Phosphorus content, Freshwater algae
Format: Document (PDF)

Peptides (10)	+ -
Synthesis (8)	+ -
Chemistry, Biochemistry (6)	+ -
Organic compounds (6)	+ -
Venom (6)	+ -

Alzheimer's disease (5)	+ -
Chemistry, Organic (5)	+ -
Organometallic polymers (5)	+ -
Amyloid (4)	+ -
Analysis (4)	+ -
Gastropoda (4)	+ -
Marine natural products (4)	+ -
Raman spectroscopy (4)	+ -
Research (4)	+ -
Structure (4)	+ -
Therapeutic use (4)	+ -
Amyloid beta-Peptides (3)	+ -
Cellular signal transduction (3)	+ -
Conus (3)	+ -
Coral reef ecology (3)	+ -
Ecology (3)	+ -
Environmental aspects (3)	+ -
Infrared spectroscopy (3)	+ -
Intermediates (Chemistry) (3)	+ -
Marine organisms (3)	+ -
Marine pharmacology (3)	+ -
Matrix Metalloproteinases (3)	+ -
Peptides -- Structure (3)	+ -
Prions (3)	+ -
Sponges (3)	+ -

Everglades (1)	+ -
Florida (1)	+ -
Lake Worth Lagoon (Fla.) (1)	+ -

Charles E. Schmidt College of Science (130)	+ -
Florida Atlantic University (101)	+ -
Du, Deguo (10)	+ -
Kerr, Russell G. (9)	+ -
Lepore, Salvatore D. (9)	+ -

Carraher, Charles E. (6)	+ -
Schultz, Franklin A. (6)	+ -
Fields, Gregg B. (5)	+ -
Terentis, Andrew C. (5)	+ -
Baird, Donald M. (4)	+ -
West, Lyndon (4)	+ -
De Lill, Daniel T. (3)	+ -
Haky, Jerome E. (3)	+ -
Mari, Frank (3)	+ -
Baker, Earl W. (2)	+ -
Cudic, Mare (2)	+ -
Cudic, Predrag (2)	+ -
Louda, J. William (2)	+ -
Parkanyi, Cyril (2)	+ -
Perumareddi, Jayarama R. (2)	+ -
Regmi, Deepika (2)	+ -
Roche, Stephane P. (2)	+ -
West, Lyndon M. (2)	+ -
Alhuniti, Mohammed (1)	+ -
Aukszi, Beatrix. (1)	+ -
BERNARD, DONALD JAMES. (1)	+ -
Barot, Girish Vallabhbhai. (1)	+ -
Battin, Amitabh J. (1)	+ -
Beckwith, Donella Marie (1)	+ -

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