A comparison of chemical and chemo-enzymatic syntheses of α-2, 3-sialylated octyl lactoside is reported. The chemical approach, starting from lactose and sialic acid, required 14 steps and proceeded in 5% overall yield; poor α-selectivity in the sialylation step necessitated a difficult and low yielding separation of anomers. A chemoenzymatic approach, employing recombinant Trypanosoma cruzitrans-sialidase to effect the key ...