Rifaximin EP Impurity H

Chemical Name:  (2S,16Z,18E,20S,21S,22R,23R,24R,25S,26R,27S,28E)-5,6,21,23-tetrahydroxy-16-(hydroxymethyl)-27-methoxy-2,4,11,20,22,24,26-heptamethyl-1,15-dioxo-1,2-dihydro2,7-(epoxypentadeca[1,11,13]trienoimino)[1]benzofuro[4,5-e]pyrido[1,2-a]benzimidazol-25-yl acetate (16-desmethyl-16-(hydroxymethyl)rifaximin)