Preparation and Chiroptical Studies of Dendritic Alkaloid Derivatives

A series of dendritic substituted alkaloids, deriving from quinine or atropine and Frechet-type dendrons up to generation three, have been prepared. Enantioseparation of the dendronized atropine ammonium salts was achieved by HPLC on chiral stationary phases. Investigation of the chiroptical properties of the series of dendrimers by circular dichroism spectroscopy revealed an influence of the chiral core on the dendritic part with regard to the intensities of the Cotton bands. The chirality was found to be dependent on its chiral elements and the generation of the formally achiral dendritic branch attached to the chiral core (“dendritic effect”). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)