INVESTIGATIONS ON THE MAGNESIUM RETAINING PROPERTIES OF TRIAMTERENE DERIVATIVES WITH AN AROMATIC SIDE-CHAIN

The influence of neutral (N) and acidic ethers (S) of 4-hydroxytriamterene with an additional aromatic substituent in the side chain on renal electrolyte excretion was investigated in rats. The same structure-activity-relationships concerning the natriuretic, antikaliuretic and antimagnesiuretic properties as found in experiments with triamterene derivatives containing an aliphatic side chain could be established. These experiments also substantiated a non-ionizable oxygen function as the structural element for a magnesium sparing effect. It could be shown that this moiety must have a defined distance to the heterocyclic nucleus of the molecule, steric hindrance decreasing the magnesium sparing properties. In conclusion, these compounds can be considered as valuable tools for the development of potassium retaining diuretics with additional magnesium sparing properties.