Abstract: Compounds of the formula ##STR1## in which R is alkyl having up to 4 carbon atoms, n has an average value of at least 9, X is a radical of the formula --C(.dbd.O)--(NH--SO.sub.2).sub.m -- in which m is 0 or 1 and, if m is 1, the carbonyl group may be bonded to the oxygen atom or to the nitrogen atom, and each of the radicals A.sub.1, A.sub.2 and A.sub.3, independently of the others, is hydrogen or an acyl radical, and salts of salt-forming compounds of formula I, as well as metal complexes of compounds of formula I, in which A.sub.1, A.sub.2 and A.sub.3 are hydrogen can be used as metal chelators and as auxiliaries in diagnosis.

Abstract: Compounds of the formula ##STR1## in which R is alkyl having up to 4 carbon atoms, n has an average value of at least 9, X is a radical of the formula --C(.dbd.O)--(NH--SO.sub.2).sub.m -- in which m is 0 or 1 and, if m is 1, the carhonyl group may be bonded to the oxygen atom or to the nitrogen atom, and each of the radicals A.sub.1, A.sub.2 and A.sub.3, independently of the others, is hydrogen or an acyl radical, and salts of salt-forming compounds of formula I, as well as metal complexes of compounds of formula I, in which A.sub.1, A.sub.2 and A.sub.3 are hydrogen can be used as metal chelators and as auxiliaries in diagnosis.

Abstract: Compounds of the formula ##STR1## in which R is alkyl having up to 4 carbon atoms, n has an average value of at least 9, X is a radical of the formula --C(.dbd.O)--(NH--SO.sub.2).sub.m -- in which m is 0 or 1 and, if m is 1, the carbonyl group may be bonded to the oxygen atom or to the nitrogen atom, and each of the radicals A.sub.1, A.sub.2 and A.sub.3, independently of the others, is hydrogen or an acyl radical, and salts of salt-forming compounds of formula I, as well as metal complexes of compounds of formula I, in which A.sub.1, A.sub.2 and A.sub.3, are hydrogen can be used as metal chelators and as auxiliaries in diagnosis.

Abstract: There is disclosed a process for the preparation of analytically pure chelate complexes which can be used in diagnostic medicine, for example as contrast media or radiopharmaceuticals. The process comprises transcomplexing a complex of a .beta.-dicarbonyl compound and a metal ion, for example a metal acetylacetonate, which is readily soluble in an organic solvent that is not miscible in all proportions with water, with a stoichiometric amount or with a less than equivalent amount of a chelating agent whose binding affinity for the metal ion is greater than that of the .beta.-dicarbonyl compound.

Abstract: Described is a novel process for the introduction of an organic acyl radical selectively at the nitrogen atom of the amino group of desferrioxamine B or of a partially O-acylated derivative thereof. It comprises treating a derivative of desferrioxamine B, in which the amino nitrogen and the hydroxy oxygen of at least one of the hydroxamic acid groupings carries an organic silyl group, with an organic acylating agent and then removing the silyl groups present. The novel N- and O-silylated starting materials can be manufactured, preferably in situ, by reacting an appropriate derivative of desferrioxamine B that has at least one hydroxy group and the amino group in free form, with an organic silicon halide.

Abstract: Described is a novel process for the introduction of an organic acyl radical selectively at the nitrogen atom of the amino group of desferrioxamine B or of a partially O-acylated derivative thereof. It comprises treating a derivative of desferrioxamine B, in which the amino nitrogen and the hydroxy oxygen of at least one of the hydroxamic acid groupings carries an organic silyl group, with an organic acylating agent and then removing the silyl groups present. The novel N- and O-silylated starting materials can be manufactured, preferably in situ, by reacting an appropriate derivative of desferrioxamine B that has at least one hydroxy group and the amino group in free form, with an organic silicon halide.

Abstract: 3-Substituted 4(1H)-pyridone compounds of formula ##STR1## wherein R.sub.1 is an unsubstituted or substituted hydrocarbon radical, X is a bond or a group of formula --O-- or --N(R.sub.3)--, wherein R.sub.3 is hydrogen or an unsubstituted or substituted hydrocarbon radical, and R.sub.2 is an unsubstituted or substituted hydrocarbon radical, or wherein R.sub.2 and R.sub.3, when taken together, are an unsubstituted or substituted divalent hydrocarbon radical, and wherein the other ring carbon atoms of the 4(1H)-pyridinone ring, independently of one another, are unsubstituted or substituted by an unsubstituted or substituted hydrocarbon radical or by etherified or esterified hydroxy, and salts of compounds of formula I with salt-forming properties, form chelate-type metal complexes, especially with trivalent metal ions, and can be used, for example, as pharmacologically active compounds.