[Synthesis of bronchospasmolytically effective beta phenylethyl-aminoalkyl-xanthines]

New theophylline and theobromine derivatives are synthetized from the beta-phenylethylaminoalkyl-xanthines, whose phenyl substituent is substitutent by one or two hydroxyl groups and partially also by other substituents. Different methods of synthesis are described, among them the production of the bronchospasmolytic 7-(3-[2-(3,5-dihydroxyphenyl)-2-hydroxy-ethylamino]-propyl)-theophylline (reproterol-HCl).