benzamidenafil benzamidenafil benzamidenafil or xanthoanthrafil is a synthetic drug that acts as a pde5 inhibitor. it has the same mechanism of action as pharmaceutical drugs used to treat erectile dysfunction, but it is not approved by any regulatory agency for such use. it has been found as an undeclared adulterant in supposedly "natural" health supplements. in 2009, the supplement manufacturer hi-tech pharmaceuticals recalled its product stamina-rx because it was adulterated with benzamidenafil. benzamidenafil names preferred iupac name n--2--5-nitrobenzamide other names xanthoanthrafil identifiers cas number 1020251-53-9 3d model (jsmol) interactive image chemspider 8286399 mesh c442640 pubchem cid 10110873 unii b6zmz878rf inchi inchi=1s/c19h23n3o6/c1-12(11-23)21-16-6-5-14(22(25)26)9-15(16)19(24)20-10-13-4-7-17(27-2)18(8-13)28-3/h4-9,12,21,23h,10-11h2,1-3h3,(h,20,24)key: zisfctxlaxiemv-uhfffaoysa-ninchi=1/c19h23n3o6/c1-12(11-23)21-16-6-5-14(22(25)26)9-15(16)19(24)20-10-13-4-7-17(27-2)18(8-13)28-3/h4-9,12,21,23h,10-11h2,1-3h3,(h,20,24)key: zisfctxlaxiemv-uhfffaoyaw smiles coc1=c(oc)c=c(cnc(=o)c2=cc(=cc=c2nc(c)co)()=o)c=c1 properties chemical formula c19h23n3o6 molar mass 389.408 g·mol−1 except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references