Stereoselective synthesis of benzyl-protected β-galactosides by propionitrile-mediated glycosylation

Abstract β-Selective galactosylation was studied using a series of 2- O -benzylated phenyl 1-thio-galactosides and glycosyl acceptors in propionitrile with BSP–TTBP–Tf 2 O. The glycosylation enabled us to synthesize useful precursors of N -acetyllactosamine and core 1 O -glycoserine derivatives in a highly convergent manner.