DO3A Trisodium Salt

About This Product

DO3A trisodium salt is 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid as its trisodium salt, formula C14H23N4Na3O6, molecular weight 412.3 and CAS number 217973-03-0. It is the cyclen ring carrying acetate arms on three of its four nitrogens. The value of DO3A lies in the nitrogen it leaves unsubstituted. With three carboxylate arms already in place, the fourth nitrogen can be given a different group, and that single choice defines the drug: alkylation with propylene oxide leads to the hydroxypropyl ligand of gadoteridol, while ring-opening of a protected dihydroxy epoxide builds the side chain of gadobutrol. Both are neutral macrocyclic complexes, because the fourth arm carries no charge and the three carboxylates exactly balance the gadolinium ion. Supplying the ligand as the trisodium salt gives a water-soluble, ready-deprotonated form for aqueous alkylation, and selective tri-substitution, without over-alkylation to DOTA, is the purity question that matters. It is used as an intermediate in gadobutrol and gadoteridol manufacture, in preparing mono-functionalised macrocyclic chelators, and in contrast-agent and radiopharmaceutical research. Bio Green Chem supplies DO3A trisodium salt with the purity, water, sodium and related-substance specification agreed with the quotation. Regulatory documentation for pharmaceutical use is confirmed at enquiry.