Mupirocin Impurity 40

9- (((E) -4- ((2S,3R,4R,5S) -5- ((2R,3S,4S,5S) -3- ((9- (((E) -4- ((2S,3R,4R,5S) -3,4-dihydroxy-5- (((2S,3S) -3- ((2S,3S) -3-hydroxybutan-2-yl) oxiran-2-yl) methyl) tetrahydro-2H-pyran-2-yl) -3-methylbut-2-enoyl) oxy) nonanoyl) oxy) -2,5-dihydroxy-4-methylhexyl) -3,4-dihydroxytetrahydro-2H-pyran-2-yl) -3-methylbut-2-enoyl) oxy) nonanoic acid