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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Synthesis and monoamine uptake inhibiting properties of perisubstituted tricyclic compounds

Peters, Jennifer Margaret, 1956- January 1988 (has links)
The synthesis of 1-methyl-promazine, 4-hydroxymethyl-iminodibenzyl, and 4-bromo-5-trimethylsilyl-iminodibenzyl via dilithiation and ¹H-NMR's are described. Molecular modeling was done for the latter compound. The heat of dissociation was 30.6 kcal/mole for the lowest energy conformer. Rotational energies were examined for three bonds. The IC₅₀ values for inhibition of neurotransmitter uptake by rat brain synaptosomes were determined for a series of 1-substituted promazines, and 4-substituted imipramines. 1-Substituted promazines were fair inhibitors of serotonin uptake with an average IC₅₀ of 2000 nm. Their potency for inhibiting norepinephrine uptake was difficult to assess due to poor assay reproducibility, and the average IC₅₀ was estimated at 200 to 1700 nm. Serotonin, but not norepinephrine, uptake inhibition was increased with additional ring substitution at C(2) with a trifluoromethyl group. The 4-substituted imipramines were equal or slightly decreased in potency to unsubstituted imipramine for uptake inhibition of both neurotransmitters. IC₅₀'s were also reported for imipramine and desipramine.
22

The synthesis and study of a crown ether functionalized with both phosphine and phenol groups

Crabill, Todd W. January 2005 (has links)
This study has resulted in a crown ether functionalized with both phosphine and phenol groups, 5-diphenylphosphino-1,3-xylyl-18-crown-5. The target molecule was obtained from a six step synthesis. 4-Bromophenol was treated in sequence with formaldehyde, dimethylsulfate, and phosphorus tribromide producing 4-bromo-2,6-bis(bromomethyl)anisole. The main intermediate, 5-diphenylphosphino-1,3-xylyl-18-crown-5, was obtained by treating 4-bromo-2,6-bis(bromomethyl)anisole in sequence with tetraethylene glycol, lithium iodide, and methyldiphenyl phosphonite. The lithium iodide cleaved the anisole-to-methyl group bond, and the methyldiphenyl phosphonite provided the phosphine group for the crown ether following a lithium bromine exchange reaction. The 31P NMR of the phosphine crown ether showed a single signal at 6 -5.9, showing consistency of a single product. The IH NMR of the phosphine crown ether in deuterated chloroform showed signals at 6 3.55-3.7 (crown CH2), 6 4.6 (benzylic CH2), 6 7.1 (d, J = 7.o Hz, crown aromatic CH2), and 6 7.2-7.4 (noncrown aromatic CH2). / Department of Chemistry
23

The total synthesis of two human urinary metabolites of delta-9-THC ; The total synthesis of (d,1)-morphine / Total synthesis of (d,1)-morphine

Kerr, Michael Andre January 1991 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1991. / Includes bibliographical references (leaves 41-43, 244-250) / Microfiche. / xiii, 374 leaves, bound ill. 29 cm
24

The biosynthesis of mollisin, islandicin, and daunomycin

Paulick, Robert Charles, January 1976 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 281-286).
25

Total synthesis of (+) and (-)- wilforonide, (+)-triptocallol, and analogs of triptolide

Xu, Ming, 徐明 January 2000 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
26

Syntheses and functionalization of block copolymers based on polystyrene-block-poly(4-vinylpyridine) and polystyrene-block-polyisoprene

侯斯健, Hou, Sijian. January 1999 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
27

Synthesis of hibiscoquinone C and experiments in the synthesis of other naturally occurring quinones

李智輝, Lee, Chi-fai. January 1996 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
28

Synthetic studies towards pseudolaric acids

Geng, Zhe., 耿哲. January 2004 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
29

PREPARATION AND REACTION OF SEVERAL DELOCALIZED DICARBANIONS.

OGLE, CRAIG ALAN. January 1982 (has links)
The literature on preparation and oxidation of carbanions is reviewed. Attempted preparation of many new carbanions, using Lochmann's base (potassium t-butoxide/n-butyllithium), is described; dianions 59, 76, and 85 were prepared for the first time. Preparation of 85, calculated to have the least delocalization energy of all six-carbon acyclic carbanions, completes the series of six-carbon acyclic dianions. Reaction of these and three other dicarbanions (o-48, m-58, and p-58) with dihalides and oxidizing agents were investigated. The shortest routes to certain {n}- and {n,n}-cyclophanes resulted. Good yields were obtained of {9}- and -metacyclophane. Several {n}-2,6-pyridinophanes were synthesized from dianion 59. {6,6}- and {7,7}-metacyclophane and {5,5}-, {7,7}-, and {9,9}- orthocyclophane were synthesized for the first time.
30

A HIGH SPEED DIGITAL IMPLEMENTATION OF LPC SPEECH SYNTHESIZER USING THE TMS320.

Jin, Yi-Xuan. January 1985 (has links)
No description available.

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