CAS No:13929-35-6||Chemical Formula:C39H49NO14||4-O-(Carboxymethyl)rifamycin; [(1,2-Dihydro-5,6,17,19,21-pentahydroxy-23- methoxy-2,4,12,16,18,20,22-heptamethyl-1,11-dioxo-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-9-yl)oxy]acetic Acid 21-Acetate (rifamycin B)