25-Desacetyl Rifaximin

Chemical Name: [2S-(2R*,16Z,18E,20R*,21R*,22S*,23S*,24S*,25R*,26R*,27R*,28E)]-5,6,21,23,25-Pentahydroxy-27-methoxy-2,4,11,16,20,22,24,26-octamethyl-2,7-(epoxypentadeca[1,11,13]trienimino)benzofuro[4,5-e]pyrido[1,2-a]benzimidazole-1,15(2H)-dione