Abstract
Asymmetric total syntheses and structure revisions of dihydroisocoumarin‐type natural products, eurotiumide A and eurotiumide B have been described. The key features of these total syntheses are the asymmetric Shi epoxidation, regio‐ and stereoselective epoxide opening, C1 insertion/lactonization cascade reaction for constructing the 4‐methoxyisochroman‐1‐one skeleton. We confirmed the structures and configurations of eurotiumide A and B on the basis of X‐ray crystallographic analysis of the key intermediate and revealed that eurotiumide A and B have cis and trans configurations at the H3/H4 positions, which indicates the opposite relationship of the stereochemistry with respect to the previous report. Their absolute configurations were also determined. These natural products are highly fluorescent in several solvents with large Stokes shifts involving the excited‐state intramolecular proton transfer mechanism, which is supported by time‐dependent density functional theory. Eurotiumide A also displays fluorescence in Bacillus cereus.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
