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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.
11

Synthesis and Characterization of Hexanuclear Rhenium Chalcogenide Clusters Containing Potential Two-Photon Absorbing Ligands and the Synthesis and Characterization of Gold-Substituted Coumarins

Updegraff, James Benjamin, III January 2010 (has links)
Thesis(Ph.D.)--Case Western Reserve University, 2010 / Title from PDF (viewed on 2009-12-30) Department of Chemistry Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
12

The metabolism of coumarin and o-coumaric acid by Fusarium solani.

Barran, Leslie R. January 1965 (has links)
The metabolism of coumarin and c-coumaric acid by plant and animals has been studied fairly extensively but only a few trials have been reported with microorganisms. A number of fungi including strains of Penicillium and Fusarium were shown to metabolise coumarin and c-coumaric acid. Umbelliferone, dihydrocoumarin, melilotic acid and cis-cis-mucomic acid, have been identified as products of coumarin degradation. [...]
13

The protein balance of normal, lymphodematous and injured tissues and the action of a benzopyrone, coumarin / R.M. Gaffney

Gaffney, R.M. (Raelene Margaret) January 1982 (has links)
Typescript (photocopy) / 172 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1982
14

The protein balance of normal, lymphodematous and injured tissues and the action of a benzopyrone, coumarin /

Gaffney, R.M. January 1982 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1982. / Typescript (photocopy).
15

Acute actions of osthole in the modulation of the vascular system

Chan, Lai-yin, Matthew. January 2007 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2008.
16

Studies on 4-hydroxycoumarins I. The attempted resolution of warfarin. II. The chemistry of 3-acyl-4-hydroxycoumarins /

Kloss, Robert Albert, January 1956 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
17

The content, distribution and some metabolic aspects of coumarin in sweet clover (Melilotus alba Des.)

Brink, Vernon Cuthbert. January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [117]-[125]).
18

Applications of the Baylis-Hillman reaction in the synthesis of coumarin derivatives

Musa, Musiliyu Ayodele January 2003 (has links)
The reaction of specially prepared salicylaldehyde benzyl ethers with the activated alkenes, methyl acrylate or acrylonitrile, in the presence of the catalyst, DABCO, has afforded Baylis-Hillman products, which have been subjected to conjugate addition with either piperidine or benzylamine. Hydrogenolysis of these conjugate addition products in the presence of a palladium-on-carbon catalyst has been shown to afford the corresponding 3-substituted coumarins, while treatment of O-benzylated Baylis-Hillman adducts with HCl or HI afforded the corresponding 3-(halomethyl)coumarins directly, in up to 94%. The 3-(halomethyl)coumarins have also been obtained in excellent yields (up to 98%) and even more conveniently, by treating the unprotected Baylis-Hillman products with HCl in a mixture of AcOH and Ac₂O, obtained from tert-butyl acrylate and various salicylaldehydes. The generality of an established route to the synthesis of coumarins via an intramolecular Baylis-Hillman reaction, involving the use of salicylaldehyde acrylate esters in the presence of DABCO, has also been demonstrated. Reactions between the 3-(halomethyl)coumarins and various nitrogen and carbon nucleophiles have been shown to proceed with a high degree of regioselectivity at the exocyclic allylic centre to afford 3-substituted coumarin products. The electronimpact mass spectra of selected coumarin derivatives have been investigated using high-resolution and B/E linked scan data. Fragmentation pathways have been proposed and fragmentation modes associated with different coumarin-containing analogues have been compared. A series of coumarin-containing analogues of ritonavir (a clinically useful HIV-1 protease inhibitor) have been prepared and characterized. The synthetic approach has involved the coupling of coumarin derivatives with a hydroxyethylene dipeptide isostere to afford ritonavir analogues containing coumarin termini. An interactive docking procedure has been used to explore the docking of ritonavir and a coumarincontaining analogue into the enzyme active site.
19

An approach to the synthesis of pimpinellin

Wang, Paul Sun-Chi 01 April 1975 (has links)
It has been over forty years since pimpinellin was isolated pure and its structure determined. We wished to explore possible routes for its total synthesis, unknown to this time. One route was via methyl 5-formyl-4,6,7-trimethoxycoumarilate. The route of Paul was reexamined through cleavage of 2,3,4,6-tetramethoxy-benzaldehyde to 2-hydroxy-3,4,6-trimethoxybenzaldehyde and its condensation to 4,6,7-trimethoxycoumarilic acid. Paul reported low yields and difficult purification steps. We were able to isolate the compounds pure but in too low yields to warrant further work at this time. Evidence suggests the synthesis of methyl 5-formyl-4,6,7-trimethoxycoumarilate, but lack of starting material and time prevented further examination now. An alternate route, via dihydrocinnamic acids followed by oxidation to quinones and reduction, would provide a needed phenolic group. We found that 2,3,4-trimethoxydihydrocinnamic acid and its ester did not form a quinone on oxidation, but ethyl 2,3,4,6-tetramethoxydihydrocinnamate did form a quinone on oxidation with chromic acid or argentic oxide.
20

Atom-economical chemoselective synthesis of furocoumarins via cascade palladium catalyzed oxidative aloxylation of 4-oxohydrocoumarins and alkenes

Tan, X., Zhao, H., Pan, Y., Wu, Na (Anna), Wang, H., Chen, Z. 02 June 2020 (has links)
No / A novel and efficient procedure for the synthesis of furo[3,2-c] coumarins from readily available 4-oxohydrocoumarins and alkenes in the presence of a catalytic amount of Pd(CF3COO)2 has been developed. Atom-economical characteristics and mild conditions of this method are in accord with the concept of modern green chemistry.

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