Chemoenzymatic synthesis of enantiomerically enriched gamma and delta lactones

Şardan, Melis
The major subject of this thesis is the synthesis of enantiomerically enriched gamma and delta lactones via Ring Closing Metathesis (RCM). Furan and thiophene substituted aldehydes were transformed to the corresponding heteroaryl substituted allylic and homoallylic alcohols by using vinyl and allylmagnesium bromide, respectively and then resultant racemic alcohols were resolved by hydrolase type enzymes (PSC-II, Lipozyme, CAL-B) with high enantiomeric excess values. Since the absolute configuration of alcohols were known, it was possible to determine the configuration of the synthesized compounds. After the enantiomeric enrichment of the alcohols, subsequent acylation with acryloyl and methacryloyl chloride afforded feasible diene system that was subjected to ring closing metathesis reaction 1st and 2nd generation Grubbs’ catalysts were used. These lactones were used to test their biological activities.


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Citation Formats
M. Şardan, “Chemoenzymatic synthesis of enantiomerically enriched gamma and delta lactones,” M.S. - Master of Science, Middle East Technical University, 2010.