The reaction of 1-bromo-3-chloropropane (I) with thiophenol (II) by means of NaOH in refluxing water gives 1-(phenylthio)-3-chloropropane (III), which is condensed with piperazine (IV) by means of NaOH in refluxing ethanol-water yielding 1-(3-phenylthiopropyl)piperazine (V). Finally, this compound is condensed with 7-(2,3-epoxypropyl)theophylline (VI) in refluxing ethanol.