Synthesis of [60]fullerene-glycopyranosylaminopyrimidin-4-one conjugates

The synthesis of several C-60 derivatives containing a 6-(beta-D-glycopyranosylamino)pyrimidin-4-one unit and a C-60-uridine conjugate is described. The fullerene derivatives bearing a 4-(beta-D-glycopyranosylamino)pyrimidin-4-one moiety were synthesised by 1,3-dipolar cycloaddition reactions Of C-60 with azomethine ylides generated in situ from the corresponding 5-formylpyrimidin-4-one derivatives and N-methylglycine. The synthesis of the C-60-uridine conjugate involved the selective protection of the 2'- and 3'-hydroxyl groups of uridine, esterification, cyclopropanation Of C-60 and, finally, the deprotection of the hydroxyl groups. One of the fullerene-glycopyranosylaminopyrimidin-4-one conjugates was characterised by single-crystal X-ray crystallography. Differentiation between pairs of diastereoisomers, for several fullerene derivatives, was achieved through the study of their gas-phase fragmentations. (c) 2008 Elsevier Ltd. All rights reserved.