Bligh, Annie Sim WanAnnie Sim WanBlighWardle, N. J.Herlihy, A. H.So, P.-W.Bell, J. D.2021-12-092021-12-092007https://repository.sfu.edu.hk/handle/sfu/2013A new synthetic pathway to 1-(2-[β,d-galactopyranosyloxy]ethyl)-7-(1-carboxy-3-[4-aminophenyl]propyl)-4,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododecane (Gal-PA-DO3A-NH<sub>2</sub>) and 1-(2-[β,d-galactopyranosyloxy]ethyl)-4,7,10-tris(carboxymethyl)-1, 4,7,10-tetraazacyclododecane (Gal-DO3A) chelating agents was developed involving full hydroxyl- and carboxyl-group protection in precursors to product. Two sequences of cyclen-N-functionalisation were subsequently investigated, one successfully, towards synthesis of the novel ‘smart’ bifunctional Gal-PA-DO3A-NH<sub>2</sub> chelate. The longitudinal proton relaxivities of the neutral [Gd-(Gal-PA-DO3A-NH<sub>2</sub>)] and [Gd-(Gal-DO3A)] complexes were increased by 28% and 37% in the presence of β-galactosidase, respectively.enSynthesis of a novel ‘smart’ bifunctional chelating agent 1-(2-[β,d-galactopyranosyloxy]ethyl)-7-(1-carboxy-3-[4-aminophenyl]propyl)-4,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododecane (Gal-PA-DO3A-NH2) and its Gd(III) complexjournal article10.1016/j.bmc.2007.05.004