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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

Chemical mechanisms of DNA cleavage by the antitumor antibiotic natural product Leinamycin /

Mitra, Kaushik, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
22

Chemical mechanisms of DNA cleavage by the antitumor antibiotic natural product Leinamycin

Mitra, Kaushik, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
23

Synthesis and acid-catalyzed polymerization of 1,6-anhydro-beta-D-glucopyranose derivatives

Wollwage, Paul C., January 1969 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1969. / Includes bibliographical references (p. 91-96).
24

Synthesis and alkaline degradation of xylobiose and 2',3',4'-tri-O-methyl-xylobiose

Kidd, James R., January 1980 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1980. / Includes bibliographical references (leaves 75-78).
25

The reactivity of the hydroxyl groups of methyl beta-D-glucopyranoside in the Koenigs-Knorr reaction

Bills, Alan M., January 1967 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1967. / Bibliography: leaves 49-51.
26

An assessment of tropospheric photochemistry over central/eastern North Pacific

DiNunno, Brian J. 05 1900 (has links)
No description available.
27

Heats of mixing for liquid systems containing chloride, hydroxyl and methylene groups : measurement and prediction by an analytical group solution model

Kalu, Egwuonwu Ukoha. January 1975 (has links)
No description available.
28

Liquid aerosol photochemistry : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry in the University of Canterbury /

Bones, David L. January 2008 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). Includes bibliographical references (p. 171-177). Also available via the World Wide Web.
29

New annulation methods : total synthesis of the diterpenoid (+--)-ambliol B

Marais, Pierre Christiaan January 1990 (has links)
The preparation of bicyclic systems containing an allylic, angular hydroxyl group (general structure 20 and compound 87b) is described. These materials have been prepared via a new annulation sequence involving (a) the alkylation of cyclic ketones with the bifunctional conjunctive reagents 129, 21 and 60, (b) the conversion of the alkylation products into keto vinyl iodides, and (c) cyclization of the keto vinyl iodides via low temperature metal halogen exchange with n-butyllithium. The cyclization process described in (c) has been employed in the first total synthesis of the diterpenoid (±)-ambliol B (94). Thus, 3,4-dimethyl-2-cyclohexen-l-one (96) was converted, in three steps, into the unstable enone 125. Reaction of this compound with the novel vinylgermane cuprate 110, followed by reaction of the resultant product with iodine, gave the cyclization precursor 106. Cyclization of 106 gave a single, trans-fused product (128) in high yield. The exocyclic methylene function of 128 was cyclopropanated and the vinyl substituent of the resultant cyclopropane was hydroborated to give the cyclopropane diol 149. Hydrogenolysis of the cyclopropane ring of compound 149 provided the required gem-dimethyl moiety. The resultant product was converted into (±)-ambliol B (94) via a four step sequence of reactions involving (a) oxidation of the primary alcohol function, (b) addition of 3-furyllithium to the so-formed unstable aldehyde, (c) acetylation of the secondary alcohol prepared in (b), and (d) reductive removal of the acetoxy function. A new annulation sequence which utilizes the vinylgermane cuprate 110 as a synthetic equivalent of the 1-butene a²,d⁴-synthon 153 is described. Thus, cyclic enones of the general structure 154 were treated with 110 to provide the keto vinylgermane intermediates 155. The latter materials were transformed into the corresponding keto vinyl iodides 156. Treatment of 156 with a palladium(0) catalyst and a base resulted in cyclization to provide the annulation products 157 or, when R₁ = H, the α,β-unsaturated ketones 185. [ Formulas omitted ] / Science, Faculty of / Chemistry, Department of / Graduate
30

Theoretical Studies of Atmospheric Water Complexes

Pan, Xiong 01 January 1992 (has links)
Intermolecular complexes between H₂O and atmospheric species HO, HO₂, H₂O₂, O₃, NO and NO₂ have been studied by ab initio molecular orbital methods. The studies have been performed to the MP2 theory level by using 4-31G, 6-31G, D95, 6-31G**, D95**, 6-311G**, 6-311+G**, 6-311++G**, 6-311+G(2d,lp) and 6-311+G(2d,2p) basis sets. The geometries were fully optimized. The vibrational frequencies were calculated. The Basis Set Superposition Error (BSSE) were estimated. Finally, the binding energies of the complexes were predicted with other thermochemical properties. The binding energies of H₂O•HO, H₂O•HO₂, H₂O•H₂O₂, H₂O•O₃, H₂O•NO and H₂O•NO₂ are estimated to be 5.7±0.6, 8.9±1.0, 7.3±1.3, 1.8±0.2, 1.17 (no BSSE correction) and 2.98 (no BSSE correction) Kcal/Mol, respectively. The Kcq for dimerization to yield H₂O•HO, H₂O•HF, H₂O•HO₂, H₂O•H₂O and H₂O•H₂O₂ are estimated to be 0.11, 2.8, 3.3, 0.067 and 0.11 atm¯¹, respectively. The H₂O•HO, H₂O•HF, H₂O•HO₂, H₂O•H₂O and H₂O•H₂O₂ are quite strongly bonded complexes, while H₂O•O₃, H₂O•NO and H₂O•NO₂ are only weakly bonded complexes. The Kcq changes with temperature are discussed, and their importance in atmospheric chemistry are addressed.

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