Abstract: 1. Compounds of general Formula I ##STR1## wherein n and m in each case mean the numbers 0, 1, 2, 3 and 4,X stands for a hydrogen atom and/or a metal ion equivalent of an element of atomic numbers 21-29, 31, 32, 37-39, 42-44, 49 or 57-83,R.sup.1 and R.sup.2, being different, mean in each case a hydrogen atom or a straight-chain, branched, saturated or unsaturated C.sub.0 -C.sub.20 -alkylene group, this alkylene group exhibiting at the end either a second molecule of general Formula I.sub.A or I.sub.

Abstract: A diagnostic medium contains at least one physiologically well tolerated complex salt comprising an anion of a complexing acid and one or more central ion or ions of an element with an atomic number of 21 to 29, 42, 44 or 57 to 83 and, optionally, one or more physiologically biocompatible cation or cations of an inorganic and/or organic base or amino acid, optionally, with additives customary in galenic formulations, dissolved or suspended in an aqueous medium.

Abstract: A diagnostic medium contains at least one physiologically well tolerated complex salt comprising an anion of a complexing acid and one or more central ion or ions of an element with an atomic number of 21 to 29, 42, 44 or 57 to 83 and, optionally, one or more physiologically biocompatible cation or cations of an inorganic and/or organic base or amino acid, optionally, with additives customary in galenic formulations, dissolved or suspended in an aqueous medium.

Abstract: A diagnostic medium contains at least one physiologically well tolerated complex salt comprising an anion of a complexing acid and one or more central ion or ions of an element with an atomic number of 21 to 29, 42, 44 or 57 to 83 and, optionally, one or more physiologically biocompatible cation or cations of an inorganic and/or organic base or amino acid, optionally, with additives customary in galenic formulations, dissolved or suspended in an aqueous medium.

Abstract: 1. Compounds of general Formula I ##STR1## wherein n and m in each case mean the numbers 0, 1, 2, 3 and 4,X stands for a hydrogen atom and/or a metal ion equivalent of an element of atomic numbers 21-29, 31, 32, 37-39, 42-44, 49 or 57-83,R.sup.1 and R.sup.2, being different, mean in each case a hydrogen atom or a straight-chain, branched, saturated or unsaturated C.sub.0 -C.sub.20 -alkylene group which optionally contains imino, phenylenoxy, phenylenimino, amido, hydrazido, ester group(s), oxygen, sulfur and/or nitrogen atom(s) and is substituted, if desired, by hydroxy, mercapto, imino, epoxy, oxo, thioxo and/or amino group(s), this alkylene group exhibiting at the end either a second molecule of general Formula I.sub.A or I.sub.B ##STR2## a functional group, or, linked by way of this functional group, a bio- or macromolecule,are valuable diagnostic and therapeutic media.

Abstract: Compounds of the general formula I: ##STR1## wherein R.sup.1 signifies a COOX group or the group ##STR2## R.sup.2 and R.sup.3 are the same or different and signify a hydrogen atom, a lower straight- or branched-chain, hydrocarbon radical, a phenyl or benzyl group or either R.sup.2 or R.sup.3 signifies the group ##STR3## or R.sup.2 or R.sup.3 together signify a trimethylene or tetramethylene radical, R.sup.4 represents a straight- or branched-chain mono- or poly-hydroxyalkyl radical, R.sup.5 represents a hydrocarbon atom, a lower straight- or branched-chain, optionally mono- or poly-hydroxylated, hydrocarbon radical, Q signifies an oxygen or sulfur atom or the group ##STR4## and X represents hydrogen atoms and/or metal ion equivalents, and their salts with physiologically harmless organic bases, are valuable complexing agents, complexes and complex salts for diagnostic imaging.

Abstract: A diagnostic medium contains at least one physiologically well tolerated complex salt comprising an anion of a complexing acid and one or more Gadolinium ions and, optionally, one or more physiologically biocompatible cation or cations of an inorganic and/or organic base or amino acid, optionally, with additives customary in galenic formulations, dissolved or suspended in an aqueous medium.

Abstract: Compounds of the general formula I: ##STR1## R.sup.1 signifies a COOX group or the group ##STR2## R.sup.2 and R.sup.3 are the same or different and signify a hydrogen atom, a lower straight- or branched-chain, hydrocarbon radical, a phenyl or benzyl group or either R.sup.2 or R.sup.3 signifies the group ##STR3## or R.sup.2 or R.sup.3 together signify a trimethylene or tetramethylene radical, R.sup.4 represents a straight- or branched-chain mono- or poly-hydroxyalkyl radical, R.sup.5 represents a hydrocarbon atom, a lower straight- or branched-chain, optionally mono- or poly-hydroxylated, hydrocarbon radical, Q signifies an oxygen or sulfur atom or the group ##STR4## wherein j signifies the numbers 1 to 4 and R.sup.