Fidaxomicin Impurity B

Chemical Name: (2R,3S,4S,5S,6R)-6-(((3E,5E,8S,9E,11S,12R,13E,15E,18S)-12-(((2R,3S,4R,5S)-3,4-dihydroxy-5-(isobutyryloxy)-6,6-dimethyltetrahydro-2H-pyran-2-yl)oxy)-11-ethyl-8-hydroxy-18-((R)-1-hydroxyethyl)-9,13,15-trimethyl-2-oxooxacyclooctadeca-3,5,9,13,15-pentaen-3-yl)methoxy)-4-hydroxy-5-methoxy-2-methyltetrahydro-2H-pyran-3-yl 3,5-dichloro-2,4-dihydroxy-6-isopropylbenzoate