Dried or frozen seeds, stems and leaves of Sosnovski hogweed were extd. with EtOAc. After removal of the solvent by vacuum evapn., the exts. were disperged in H(2)O and reextd. with n-hexane, tetrahydrofurane, CH(2)Cl(2), PhMe and CCl(4) to sep. the exts. into resp. fractions. Psolarene, angelicine, Me(CH(2))(7)OAc and 15-pentadecanolide were identified in the fractions by gas chromatog., IR and (1)H-NMR spectroscopy.