| abstract |
Aromatically substituted azacycloalkylalkanediphosphonic acids of the formula ##STR1## in which R represents an aromatically substituted azacycloaliphatyl radical that is bonded to the group alk by way of a nitrogen atom and that optionally contains an additional nitrogen atom, and alk represents a divalent aliphatic radical, and their salts, can be used for the treatment of illnesses that can be attributed to calcium metabolism disorders. They are manufactured, for example, by reacting a compound of the formula n n R--alk--X.sub.3 (IV) n n in which X 3 represents carboxy, carbamoyl or cyano, with phosphorus acid and phosphorus trichloride and in an intermediate of the formula ##STR2## obtained by starting from compounds of the formula IV in which X 3 represents cyano or carbamoyl and by working up by hydrolysis, or in a salt thereof, replacing the amino group by hydroxy by treatment with nitrous acid. |