Abstract
The rapid conversion of D-galactose, its 2-deoxy, 3-deoxy, 4-deoxy and 6-deoxy derivatives and L-arabinose to their UDP-derivatives (2-7) is described. The procedure involves the in situ preparation of the per-O-trimethylsilylated glycopyranosyl iodides and their direct reaction with UDP. All six sugar nucleotides were active as substrates for β(1→4)-galactosyltransferase and were used to enzymatically prepare N-acetyllactosamine (8) and five of its analogs (9-13).