| abstract |
Compounds of the formula <IMAGE> wherein R1 and R2, which may be identical to or different from each other, are each independently hydrogen, straight or branched alkyl of 1 to 8 carbon atoms or arylmethyl; or R1 and R2, together with each other, are -(CH2)4 or -(CH2)5-; and R3 and R4, which may be identical to or different from each other, are each independently hydrogen, straight or branched alkyl of 1 to 4 carbon atoms or arylmethyl; or R3 and R4, together with each other, are -CH3- or -CH2-CH2-; and non-toxic, pharmacologically acceptable acid addition salts thereof. The compounds as well as their salts are useful for the treatment of cardiovascular diseases, especially hypertension. |