Keteneylidenetriphenylphosphorane as a 'C2O building block' in the synthesis of highly functionalised tetramic and tetronic acids

Naturally occurring 4-hydroxy-pyrrol-2(5H)-ones and 4-hydroxy-furan-2(5H)-ones are known to possess a wide range of biological activities such as anti-viral and tumour inhibition. For this reason, the synthesis of a number of these compounds was attempted, namely Tenuazonic Acid, Reutericyclin and Carlosic acid. A general synthesis of 4-hydroxy-pyrrol-2-ones was established by reaction of a phosphorus ylide (Ph3PCCO) with a variety of amino esters. A number of derivatives were prepared with varying substituents at the 3- and 5-positions of the nitrogen heterocycle. A general method for the preparation of highly functionalised furan-2-ones from simple alpha-hydroxy esters was also developed. Progress has been made in the synthesis of N-substituted pyrrol-2-ones where simple amide esters were reacted with a phosphorus ylide (Ph3PCCO) in the construction of highly functionalised nitrogen heterocycles. A new acylation procedure was developed in order to selectively introduce an acetyl residue to pyrrolidine-2-ones and furan-2-ones. A phosphorus ylide (Ph3PCCO) and its solid supported variant were used as acylating agents under relatively mild, basic conditions. Complex heterocycles were prepared using the Diels-Alder methodology and from reaction of Ph3PCCO with relatively simple molecules.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Bayreuth

Year

2004

Author dc:creator

• Melanophy, Claire

Contributors dc:contributor

• Schobert, Rainer

Repository record source_url

https://epub.uni-bayreuth.de/id/eprint/919/

OAI identifier oai:identifier

oai:epub.uni-bayreuth.de:919