N-Substituted derivatives of 7-(3-amino-2-hydroxypropyl)-8-benzyl- (V), or -8-phenyltheophylline (VI) were prepared by addition of the appropriate amines to 7-epoxypropyl-8-benzyl- (III), or -8-phenyltheophyllines (IV). Compounds III and IV were obtained by alkylation of 8-benzyl-, or 8-phenyltheophyllines with 1-chloro-2,3-epoxypropane. DerivativesV and VI exhibited a peripheral vasodilatation effect in vitro.