Simultaneous stereoselective 4-amination with cyclic secondary amines and 2-O-deacetylation of peracetylated sialic acid derivatives

Treatment of methyl 5-acetamido-2,4,7,8,9-penta-O-acetyl-3,5-dideoxy-β-l-glycero-d-galacto-2-nonulopyranosidonate (1) with cyclic secondary amines in pyridine at room temperature for 24 h afforded unusual products (2a–g). Related experiments were carried out to explain the formation of 4-amination and 2-O-deacetylation of peracetylated sialic acid derivatives (2a–g). This reaction may provide a new strategy for the preparation of Zanamivir analogues as neuraminidase inhibitors for anti-H5N1 subtype of avian influenza virus (AIV).