Isoquinoline derivatives and their preparation

The disclosure is made of 1-[1-(3,4-dimethoxyphenyl)-3-aminopropyl]-6,7-dimethoxyisoquinoline, corresponding to the general formula (I): < IMAGE > in which - R1 represents a hydrogen atom or a methyl radical and - R2 represents an alkyl radical comprising 1 to 5 carbon atoms or a cycloalkyl radical comprising 5 to 7 carbon atoms, the alkyl or cycloalkyl radical being optionally substituted by a hydroxyl, phenyl or phenoxy radical and the cycloalkyl radical being optionally substituted by an alkyl radical comprising 1 to 5 carbon atoms, the therapeutically acceptable salts thereof and a process for the preparation thereof. The compounds can be used as active components in therapeutic compositions intended for the cardiovascular field.