Collect. Czech. Chem. Commun. 1989, 54, 166-188

Arctolide-revision of its stereostructure and determination of absolute configuration. Detailed 1H and 13C NMR analysis

Miloš Buděšínskýa, David Šamana, Jan Pelnařa, Soňa Vašíčkováa, Bohdan Drożdżb, Halina Grabarczykb, Le Viet Ngoc Phuongb and Miroslav Holuba

a Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6, Czechoslovakia
b Department of Medicinal Plants, Academy of Medicine, Poznań, Poland


The stereostructure of arctolide-a sesquiterpenic lactone isolated from Arctotis grandis-has been revised on the basis of detailed 1H and 13C NMR analysis and detection of intramolecular hydrogen bonding by IR spectroscopy. Its absolute configuration, represented by formula Ia, was determined from the CD spectra. The scope and limitation of modern 1D- and 2D-NMR techniques in obtaining parameters utilizable for structure determination of natural compounds have been verified.