Crystal structure of nafamostat dimesylate

Fujii, Isao

Nafamostat dimesylate {systematic name: [amino({6-[(4-{[amino(iminiumyl)methyl]amino}phenyl)carbonyloxy]naphthalen-2-yl})methylidene]azanium bis(methanesulfonate)}, C(19)H(19)N(5)O(2) (2+)·2CH(3)O(3)S(−), is a broad-spectrum serine protease inhibitor and has been applied clinically as an anti­coagulant agent during hemodialysis and for treatment of severe acute pancreatitis (SAP). Since nafamostat contains flexible moieties, it is necessary to determine the conformation to understand the structure–activity relationships. The divalent cation has a screw-like motif. The guanidinium group is approximately perpendicular to the naphthyl ring system, subtending a dihedral angle of 84.30 (14)°. In the crystal, the nafamostat mol­ecules form columnar structures surrounded by a hydro­philic region.