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

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. [...]

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

Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1982. / Typescript (photocopy).

Thesis (Ph. D.)--University of Hong Kong, 2008.

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.

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]).

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.

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.

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