Circular dichroism-LI

The conformation of the cyclopentenones 5 to 8 is determined from their CD-spectra. The site of enolization and the conformation of cis- and trans-isohumulone (1 and 2) is determined with the help of the CD-spectra, the direction of enolization for the humulinic acids 3 and 4 is tentatively determined by the same method.