Selamectin EP Impuity B

Chemical Name: (2aE,2′S,4E,5′S,6S,6′R,7S,8E,11R,15S,17aR,20Z,20aR,20bS)-6′-cyclohexyl-7-[(2,6-dideoxy-3-O-methyl-α-L-arabino-hexopyranosyl)oxy]-20b-hydroxy-20-(hydroxyimino)-5′,6,8,19-tetramethyl-5′,6,6′,7,10,11,14,15,17a,20,20a,20b-dodecahydrospiro[2H,17H-11,15-methanofuro[4,3,2-pq][2,6]benzodioxacyclooctadecine-13,2′-pyran]-17-one ((5Z,25R)-25-cyclohexyl-4′-O-de(2,6-dideoxy-3-O-methyl-α-L-arabino-hexopyranosyl)-5-demethoxy-25-de(1-methylpropyl)-5-(hydroxyimino)avermectin A1a)