Diagnostic And Radiotherapeutic Contrast Agents And Process For Their Preparation

1) A compound of formula (I)

• wherein:
• R is, the same or different and each independently, a group selected from hydroxyl (—OH), acetate (—OCOCH3), sulphate (—OSO3H), phosphate
• (—OPO3H2), amino (—NH2) and acetylamino (—NHCOCH3);
• or one of the R groups is as above defined and the other is a straight or branched saccharidic or oligosaccharidic chain;
• R′ is, the same or different and each independently, a group selected from hydroxyl (—OH), acetate (—OCOCH3), sulphate (—OSO3H), phosphate
• (—OPO3H2), amino (—NH2) and acetylamino (—NHCOCH3);
• R1 and R2 are, the same or different and each independently selected from the group consisting of hydroxymethyl
• (—CH2OH), carboxyl optionally esterified with a straight or branched
• C1-C4 alkyl chain (—COOH, —COOAlk), a group of formula (II)
• —CH2—O—CH2—CH(OH)—CH2R3 (II)
• and a group —CH2R3;
• R3 is, independently in each occurrence, a diagnostically or radiotherapeutically effective chelating moiety labeled with a paramagnetic metal ion or radionuclide, bearing a terminal amino group for its linkage (—NH—) with the rest of the molecule;
• and the pharmaceutically acceptable salts thereof.