Phase transfer catalyzed reaction was used for the high yielding synthesis of aryl 1-thio-β-d- galacto-and lacto-pyranosides carrying a panel of substituents on the phenyl groups. Best galectin-1 inhibitors were simple p-nitrophenyl thiogalactoside 5a for the monosaccharide and o-nitrophenyl thiolactoside 6f or napthylsulfonyl lactoside 8c, both being 20 times better relative to natural ligands. Relative inhibitory properties as low as 2500 and 40μM were ...
