Synthesis of Neu5Ac-α-C-galactopyranosyl-functionalized magnetic nanoparticles via click chemistry

A new type of glyco-nanoparticle has been accomplished through Cu(I)-catalyzed 1,3-dipolar cycloaddition of 6-azidohexyl Neu5Ac-α-C-galactoside and N-propargyl derivative, which was attached on a silica-wrapping magnetic nanoparticle. Neu5Ac-α-C-galactoside was stereo-selectively synthesized in 11 steps from isopropyl thiogalactopyranoside and per-acetylated Neu5Ac phenylsulfone using samarium-mediated reductive desulfonylation as the key step. Magnetic nanoparticles were prepared with one-step hydrothermal method and a subsequent coating with (N,N′-di-propargyl-3-aminopropyol) triethoxysilane derivative.