Influenza virus neuraminidase (NA) catalyses the cleavage of sialic acid re
sidues terminally linked to glycoproteins and glycolipids and plays an impo
rtant role in the replication of the virus. Recently. several potent NA inh
ibitors have been synthesized based on the rational design of mimicking the
transition state of the sialic acid cleavage. Zanamivir and oseltamivir (G
S 4104. the prodrug of GS 4071) have emerged as promising influenza NA inhi
bitors for the treatment and prophylaxis of human influenza virus infection
. This review describes the recent work toward the discovery and developmen
t of influenza NA inhibitors.