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Cytotoxic peptides from marine sponges
Title
Cytotoxic peptides from marine sponges.
Creator
Gulavita, N. K., Wright, Amy E., McCarthy, Peter J., Pomponi, Shirley A., Longley, Ross E.
Date Issued
1996
PURL
http://purl.flvc.org/fau/fd/FA00007341
Subject Headings
Sponges, Peptides, Cytotoxins, Stereochemistry
Format
Document (PDF)
Novel compounds isolated from the marine sponge Clathria sp.
Title
Novel compounds isolated from the marine sponge Clathria sp.
Creator
Rueda de Leon, Rolando, Gupta, Prasoon, West, Lyndon, Graduate College
Date Issued
2011-04-08
PURL
http://purl.flvc.org/fcla/dt/3164772
Subject Headings
Sponges, Stereochemistry, Marine pharmacology
Format
Document (PDF)
Synthetic Analogues of the Microtubule-Stabilizing Agent (+)-Discodermolide: Preparation and Biological Activity
Title
Synthetic Analogues of the Microtubule-Stabilizing Agent (+)-Discodermolide: Preparation and Biological Activity.
Creator
Gunasekera, Sarath P., Mickel, Stuart J., Daeffler, Robert, Niederer, Daniel, Wright, Amy E., Linley, P. A., Pitts, Tara P.
Date Issued
2004
PURL
http://purl.flvc.org/FCLA/DT/3164107
Subject Headings
Microtubules, Cancer --Research, Biopharmaceutics, Molecular biology, Stereochemistry
Format
Document (PDF)
jj-coupling scheme by tensor operators and a thorough interpretation of the spectra of some nickel(II) complexes
Title
The jj-coupling scheme by tensor operators and a thorough interpretation of the spectra of some nickel(II) complexes.
Creator
Alves, Gelio., Florida Atlantic University, Perumareddi, Jayarama R.
Abstract/Description
The ligand field theory of complexes has been completely developed and the energy matrix elements for complexes in various geometries in different coupling schemes have been worked in considerable detail. However for many coupling schemes the computing of energy matrix elements is a tedious and laborious process. In the first part of my thesis we present a solution to the Weak-Field II problem using ladder operators and tensor operators. We used the Weak-Field II as an example to stress the...
Show moreThe ligand field theory of complexes has been completely developed and the energy matrix elements for complexes in various geometries in different coupling schemes have been worked in considerable detail. However for many coupling schemes the computing of energy matrix elements is a tedious and laborious process. In the first part of my thesis we present a solution to the Weak-Field II problem using ladder operators and tensor operators. We used the Weak-Field II as an example to stress the complexity of computing energy matrix elements using ladder operators versus the simplicity of calculating matrix elements with tensor operators. Also the Weak-Field II was used as a model example hoping to be able to accomplish the same with the jj-II coupling scheme. In the last part of my thesis we present a derivation of simplifying expressions for the energy matrix elements for the d 2 complex in the jj-II coupling scheme. It is worth mentioning that the expressions derived can be applied to complexes other than octahedral and further they can be generalized for complexes with n-electrons in the valence shell. Finally, we present a thorough analysis of the electronic spectra of some Nickel(II) complexes.
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Date Issued
2005
PURL
http://purl.flvc.org/fcla/dt/13256
Subject Headings
Ligand field theory, Quantum chemistry, Stereochemistry
Format
Document (PDF)
Lasonolides C—G, Five New Lasonolide Compounds from the Sponge Forcepia sp.
Title
Lasonolides C—G, Five New Lasonolide Compounds from the Sponge Forcepia sp.
Creator
Wright, Amy E., Chen, Ying, Winder, Priscilla L., Pitts, Tara P., Pomponi, Shirley A., Longley, Ross E.
Date Issued
2004
PURL
http://purl.flvc.org/FCLA/DT/3164109
Subject Headings
Macrolide antibiotics, Natural products, Mass spectrometry, Sponges, Stereochemistry
Format
Document (PDF)
Stereochemical determination of dictyostatin, a novel microtubule-stabilising macrolide from the marine sponge Corallistidae sp.
Title
Stereochemical determination of dictyostatin, a novel microtubule-stabilising macrolide from the marine sponge Corallistidae sp.
Creator
Paterson, Ian, Britton, R., Delgado, Oscar, Wright, Amy E.
Date Issued
2004
PURL
http://purl.flvc.org/fau/fd/FA00007061
Subject Headings
Macrolides, Sponges, Tubulin Modulators, Stereochemistry, Microtubules, Polyketides, Antimitotic Agents
Format
Document (PDF)
Revised stereochemistry for the structures of eudistomins C, K, E, F and L
Title
Revised stereochemistry for the structures of eudistomins C, K, E, F and L.
Creator
Blunt, J. W., Lake, R. J., Munro, M. H. G., Harbor Branch Oceanographic Institute
Date Issued
1987
PURL
http://purl.flvc.org/FCLA/DT/3353801
Subject Headings
Carbolines, Stereochemistry, Ascidians, Nuclear magnetic resonance spectroscopy, Sea urchins--New Zealand
Format
Document (PDF)
Catalytic Asymmetric Isomerizations of Alkynes To Allenes And Their Diastereoselective Functionalization Facilitated By An Organomanganese Auxiliary
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)