Palamivir is a cyclopentane derivative designed and synthesized by Babu and others on the basis of analyzing the

interaction mechanism and structure-activity relationship of sialic acid, zanamivir, oseltamivir and Na. The groups

connected with the ring include hydrophilic carboxyl group and guanidine group, and hydrophobic isoamyl group

and acetylamino group. Four groups with different polarity act on different active sites in the structure of influenza

virus NA. The strong intermolecular interaction was formed between the carboxyl group and the three arginine

residues ARG118, arg292 and arg371 of the Na active site, the methyl group of acetylamino group and Trp 178 and

ile 222 of the Na hydrophobic pocket, the carbonyl oxygen and arg152, the guanidine group and ASP 151, Glu 119,

Glu 227 and Trp of the Na active site 227 has strong intermolecular interaction; for influenza B Na, the isoamyl part

has strong interaction with the hydrophobic pocket formed by ala 246, Arg 224 and ile222, while for influenza A Na,

the isoamyl part has strong interaction with the hydrophobic part of Glu 276. Several groups of paramivir act on several

active sites of influenza virus NA, which strongly inhibit the activity of Na and prevent the replication and release of