The synthesis of alpha-D-glucopyranosyl 1-(methylenediphosphonate) (11), alpha-D-galactopyranosyl 1-(methylenediphosphonate) (14), and alpha-D-mannopyranosyl 1-(methylenediphosphonate) (17) has been accomplished. [(Di-phenoxyphosphinyl)methyl]
phosphonic acid (
diphenyl-MDP) (5), synthesized by two different procedures, was fused with beta-D-glucopyranose pentaacetate followed by catalytic hydrogenation to give 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl methylenediphosphonate (
glucose-MDP) (10). The anomeric configuration of 10 was assigned on the basis of NMR spectral studies. Condensation of 10 with 2',3'-di-O-acetyladenosine was accomplished by using 1-(mesitylene-2-sulfonyl)-3-nitro-1,2,4-triazole (MSNT) as coupling agent, and removal of the blocking groups gave
adenosine 5'-[(alpha-D-glucopyranosylhydroxyphosphinyl)methyl]
phosphonate (20).
Uridine 5'-[(alpha-D-galactopyranosylhydroxyphosphinyl)methyl]
phosphonate (23) and
guanosine 5'-[(alpha-D-mannopyranosylhydroxyphosphinyl)methyl]
phosphonate (26) were similarly prepared. Using a specific
glycoprotein galactosyltransferase (EC 2.4.1.38) assay,
uridine 5'-[(alpha-D-galactopyranosylhydroxyphosphinyl)methyl]
phosphonate (23) demonstrated competitive inhibition with an apparent Ki of 97 microM. The
adenosine analogue did not inhibit the
enzyme. None of the above compounds show any in vitro antitumor or
antiviral activity. Such specific inhibitors of
glycosyltransferases may serve as specific probes to study various
glycosyltransferases that might be involved in the process of
metastasis.