Mupirocin calcium Imp. C (EP):(4E)-9-[[(2E)-4-[(2S,3R,4R,5S)-3,4-dihydroxy-5-[[(2S,3S)3-[(1S,2S)-2-hydroxy-1-methylpropyl]oxiranyl]methyl]tetrahydro-2H-pyran-2-yl]-3-methylbut-2-enoyl]oxy]non-4-enoic acid (pseudomonic acid D.