Spiramycin EP Impurity A

Chemical Name: (4R,5S,6S,7R,9R,10R,11E,13E,16R)-6-[[3,6-dideoxy-3-(dimethylamino)-β-d-glucopyranosyl]oxy]-4-hydroxy-5-methoxy-9,16-dimethyl-7-(2-oxoethyl)-10-[[2,3,4,6-tetradeoxy-4-(dimethylamino)-β-d-erythro-hexopyranosyl]oxy]oxacyclohexadeca-11,13-dien-2-one (neospiramycin I),