Cyclen Butanetriol Tetrahydrochloride (Gadobutrol Intermediate)

About This Product

This intermediate is 3-(1,4,7,10-tetraazacyclododecan-1-yl)butane-1,2,4-triol as its tetrahydrochloride, also named 10-[(1RS,2SR)-2,3-dihydroxy-1-(hydroxymethyl)propyl]-1,4,7,10-tetraazacyclododecane tetrahydrochloride. Its formula is C12H28N4O3·4HCl (C12H32Cl4N4O3), molecular weight 422.2 and CAS number 156077-56-4, and it is a white to yellowish powder. It sits one step from the ligand of gadobutrol. The trihydroxybutyl side chain that gives gadobutrol its high water solubility is already attached to one ring nitrogen, typically built by opening a protected epoxide with cyclen and removing the acetonide; carboxymethylation of the three remaining nitrogens then gives the ligand, which is complexed with gadolinium. Because it is so close to the drug substance, the specification reads like an API's: identity by carbon-13 NMR and by chromatographic retention, specific rotation between −0.2° and +0.2° consistent with the racemic (1RS,2SR) form, hydrochloride content of 25.0 to 34.5 percent, and residual methanol and toluene held to 3,000 and 890 ppm, the ICH Q3C limits for those solvents. It is used as the key intermediate in gadobutrol manufacture and in the synthesis of related neutral macrocyclic gadolinium complexes for MRI contrast-agent development. Bio Green Chem supplies this gadobutrol intermediate at 98 percent minimum to specification on appearance, identification, specific rotation, water, residue on ignition, hydrochloride content and residual solvents, packed in fibre drums or bags. Regulatory documentation for pharmaceutical use is confirmed at enquiry.