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A study of inhibitor-scale interaction in carbon dioxide corrosion of mild steel /Chokshi, Kunal K. January 2004 (has links)
Thesis (M.S.)--Ohio University, June, 2004. / Includes bibliographical references (p. 103-106).
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Research in photosynthesis.Anderson, Joan Mary. January 1959 (has links)
Thesis--University of California, Berkeley, 1959. / "Biology and Medicine" -t.p. "TID-4500 (15th Ed.)" -t.p. Includes bibliographical references (p. 109-113, 156-158).
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A study of inhibitor-scale interaction in carbon dioxide corrosion of mild steelChokshi, Kunal K. January 2004 (has links)
Thesis (M.S.)--Ohio University, June, 2004. / Title from PDF t.p. Includes bibliographical references (p. 103-106)
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Corrosion inhibition of mild steel in acid environment using heterocyclic compoundsAli, Shakir A. January 1984 (has links)
No description available.
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Propoxyphene, Norpropoxyphene, and Proadifen (SKF-525A) Are Mechanism Based Inhibitors of CYP3A4, CYP3A5, and CYP3A in Human Liver MicrosomesRiley, Anna Ruth 18 March 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this study is to determine if propoxyphene and norpropoxyphene
are mechanism-based (irreversible) inhibitors of CYP3A, and to determine if
propoxyphene and norpropoxyphene are reversible inhibitors of CYP3A. Mechanismbased
inhibition is a type of irreversible inhibition that results from an inhibitor or its
metabolite binding to an enzyme during drug metabolism, which renders the enzyme
nonfunctional.
Propoxyphene is an analgesic that is frequently prescribed in the United States
and Europe. It is metabolized by CYP3A enzymes, and is an irreversible inhibitor of
CYP3A4. The major metabolite of propoxyphene is norpropoxyphene, which has not
been extensively studied for enzyme inhibition. Proadifen (SKF-525a) is not a marketed
drug, but it is a known CYP inhibitor that is structurally similar to propoxyphene and
norpropoxyphene. Propoxyphene, norpropoxyphene, and proadifen were characterized in
these studies with CYP3A4(+b5), CYP3A5(+b5) and pooled human liver microsomes.
Time-dependent and concentration-dependent loss of activity of CYP3A was measured
by formation of testosterone product. Propoxyphene and norpropoxyphene exhibited the
greatest inhibition with CYP3A in human liver microsomes, followed by CYP3A4(+b5),
and CYP3A5(+b5). Both compounds formed metabolic-inhibitor complexes with
vi
CYP3A4(+b5) and CYP3A5(+b5), but not with human liver microsomes. Proadifen was
a more potent inhibitor of CYP3A4(+b5) than of human liver microsomes and
CYP3A5(+b5). The KI values of propoxyphene and CYP3A4(+b5) and human liver
microsomes fall within the range of reported therapeutic blood levels of propoxyphene,
with reversible inhibition constants (Ki values) above therapeutic blood concentrations
for propoxyphene and norpropoxyphene. The KI values of norpropoxyphene and
CYP3A4(+b5) and human liver microsomes are higher than most reported blood levels,
except for blood levels after repeated dosing of propoxyphene at high concentrations. The
predicted change in the area under the plasma concentration versus time curve of an
orally administered CYP3A substrate with propoxyphene (AUC'po/AUCpo) was calculated
for common CYP3A substrates. The AUC'po/AUCpo ratios are four to twenty-five times
higher with co-administration of propoxyphene based on in vitro kinetic parameters.
Propoxyphene and norpropoxyphene may cause adverse events when chronically
administered at high doses and/or when co-administered with other CYP3A substrates.
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Isolation and characterization of chlorate-resistant mutants in Arabidopsis thaliana /Feldman, Kenneth A. January 1985 (has links)
No description available.
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Production of nitrous oxide by nitrification and the effect of acetylene on nitrifying bacteriaHynes, Russell K. (Russell Kenneth) January 1983 (has links)
No description available.
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Synthesis of dehydroperloline and of lactam antagonists of gamma - aminobutyric acid ( GABA )Thach, Duong January 1976 (has links)
Part I of this thesis describes the synthesis of dehydro - perloline ( 3 ), a non basic material obtained from the degradation of the alkaloid perloline ( 1 ), the major alkaloid of New Zealand rye grass. Since a crucial reaction in this sequence involved a Schmidt reaction of fluorenols 4 or 5, some of the mechanistic aspects of this reaction have been investigated. Part II describes the synthesis of caprolactam derivatives 7 with the aim at finding new antagonists or analogues of the CNS inhibitory transmitter, gamma - aminobutyric acid ( GABA ). In Chapter 1, the synthesis of N - alkyl and N - arylcaprolac - tams is described. In Chapter 2, the synthesis, by several methods, of simple 3 - alkylcaprolactams is investigated. Chapter 3 describes synthetic methods for the preparation of 4 - substituted caprolactams. Chapter 4 presents the preparation of 5 - alkyl and 7 - alkyl - caprolactams by the Schmidt reaction on 4 - alkyl and 2 - alkylcyclo - hexanones. Chapter 5 describes some investigations of possible syntheses of 6 - alkylcaprolactams. Chapter 6 contains the results of testing of some lactams and thiolactams as well as their structure - activity relationships. / Thesis (Ph.D.)--Department of Organic Chemistry, 1976.
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Progress towards the stereoselective synthesis of cycleanine.Litedu, Eunice Madira. January 2011 (has links)
The emergence of multi-drug resistance (MDR) to antimalarial and anticancer drugs has
stimulated a search for novel MDR inhibitors/reversers. Bisbenzylisoquinoline alkaloids
(BBIQ) are potential agents for reversing MDR, especially when used as synergistic enhancers
of anticancer and antimalarial drugs with improved therapeutic efficacy. Despite numerous
useful biological activities reported for BBIQ’s, the various syntheses of individual members
remained cumbersome and the overall yields are low. In addition, published methods are nonstereospecific
and produced racemates.
The aim of this project was to develop a synthetic pathway for the preparation of cycleanine, a
natural BBIQ with a symmetrical structure. The protocols developed for the synthesis of
cycleanine will serve as a template for the synthesis of other BBIQ’s with more complex
structures. The only published total synthesis of cycleanine did not address regioselectivity and
stereoselectivity, furthermore, key steps suffered from extremely low yields of the products.
Our synthetic pathway is a chiral auxiliary-based asymmetric synthesis that generates
enantioselectively a 1,2,3,4-tetrahydroisoquinolines (THIQ) monomers. Cheap, commerciallyavailable
starting materials were used to prepare monomers in a regioselective as well as
stereoselective manner in good yields. The key feature of this method entails coupling of a
chiral β-phenethylamine and halophenylacetaldehyde using the Pictet-Spengler reaction. Due
to the difficulties encountered during the course of the preparation of monomers, different
methods were tried and formation of unanticipated products rationalised. Dimeric BBIQ’s are
constituted of monomeric THIQ’s which are reported to have array of biological properties
including MDR reversing activities, therefore, the total synthesis of cycleanine will serve two
purposes.
In this investigation, the THIQ monomers were synthesised by a pathway that avoid harsh
reaction conditions. Major reactions employed include nucleophilic aromatic substitutiton,
Wittig reaction, hydroboration and IBX oxidation. Some of the steps were attempted on model
compounds to optimise the conditions prior to attempting the reaction on cycleanine
precursors. Two major contributions toward the synthesis of BBIQ’s were made in this study.
The reaction conditions to control the regioselectivity and enantioselectivity of the Pictet-
Spengler reaction for the preparation of THIQ moiety were developed. A major drawback of
the published syntheses of BBIQ’s is the harsh conditions and low yields associated with the
Ullmann reaction, which is used in the formation of the diaryl ether bonds. We have shown
that the microwave-assisted nucleophilic aromatic substitution of aryl fluorides provide a much
superior method for the formation of the key diaryl ether bond.
Although we failed to form the final diaryl ether bond, the pitfalls encountered in the synthetic
pathway are discussed and potential solutions are presented. The developed synthetic
pathways are of general applicability and therefore can also be employed in the synthesis of
other macrocyclic natural products containing diaryl ethers. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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Synthesis of dehydroperloline and of lactam antagonists of gamma - aminobutyric acid ( GABA )Thach, Duong January 1976 (has links)
Part I of this thesis describes the synthesis of dehydro - perloline ( 3 ), a non basic material obtained from the degradation of the alkaloid perloline ( 1 ), the major alkaloid of New Zealand rye grass. Since a crucial reaction in this sequence involved a Schmidt reaction of fluorenols 4 or 5, some of the mechanistic aspects of this reaction have been investigated. Part II describes the synthesis of caprolactam derivatives 7 with the aim at finding new antagonists or analogues of the CNS inhibitory transmitter, gamma - aminobutyric acid ( GABA ). In Chapter 1, the synthesis of N - alkyl and N - arylcaprolac - tams is described. In Chapter 2, the synthesis, by several methods, of simple 3 - alkylcaprolactams is investigated. Chapter 3 describes synthetic methods for the preparation of 4 - substituted caprolactams. Chapter 4 presents the preparation of 5 - alkyl and 7 - alkyl - caprolactams by the Schmidt reaction on 4 - alkyl and 2 - alkylcyclo - hexanones. Chapter 5 describes some investigations of possible syntheses of 6 - alkylcaprolactams. Chapter 6 contains the results of testing of some lactams and thiolactams as well as their structure - activity relationships. / Thesis (Ph.D.)--Department of Organic Chemistry, 1976.
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