Popis: |
The ORD curves of some alkaloids of the cinchona family and their 9-chloro-9-deoxy, 9-deoxy-, 9-oxo-, 8,9-anhydro-, 9-epi- and apo-derivatives have been examined. Most of the Cotton effects could be ascribed to the optical anisotropy of the quinoline ring or some more complex chromophore such as the carbonyl group conjugated with the aromatic ring as in 9-oxo-derivatives. The CD curves of three of these compounds confirmed the Cotton effects at long wavelength resulting from the anisotropy of the aromatic quinoline ring. The mutarotation of the 9-oxo-derivatives has been studied by ORD. |