Abstract: A chelated compound of the formula: ##STR1## where R.sub.1 is independently at each occurrence, R.sub.2, ##STR2## R2 is independently at each occurrence hydrogen, lower alkyl, lower alkyl ester, lower alkyl ether, hydroxy or halogen; A is H, Li, Na, Ca+, Mg+ or Zn+; and Mn is trivalent manganese; provided that, at least two and no more than three R.sub.1 radicals are ##STR3## The compound of the invention is particularly suitable for use in a physiologically compatible composition comprising a physiologically compatible liquid carrier for magnetic resonance imaging. The compound is also suitable as a chelate for removal of manganese from a system.The invention also comprises a method for enhanced magnetic imaging of a mammal organism which comprises introducing the composition at a level of from 20 to 200 mg/Kg of body weight into the circulatory system of the organism; and making a magnetic resonance image of at least a portion of said organism at from 30 minutes to 36 hours after said introduction.

Abstract: A chelated compound of the formula: ##STR1## where R.sub.1 is independently at each occurrence, ##STR2## R.sub.2 is independently at each occurrence hydrogen, lower alkyl, lower alkyl ester, lower alkyl ether, hydroxy or halogen; A is H, Li, Na, Ca+, Mg+or Zn+; and Mn is trivalent manganese; provided that, at least two and no more than three R.sub.1 radicals are ##STR3## The compound of the invention is particularly suitable for use in a physiologically compatible composition comprising a physiologically compatible liquid carrier for magnetic resonance imaging. The compound is also suitable as a chelate for removal of manganese from a system.The invention also comprises a method for enhanced magnetic imaging of a mammal organism which comprises introducing the composition at a level of from 20 to 200 mg/Kg of body weight into the circulatory system of the organism; and making a magnetic resonance image of at least a portion of said organism at from 30 minutes to 36 hours after said introduction.