Misoprostol Imp. A (EP): mixture of methyl 7-[(1RS,2SR,3SR)-3-hydroxy-2-[(1E,4RS)-4-hydroxy-4-methyloct-1-enyl]-5-oxocyclopentyl]heptanoate and methyl 7-[(1RS,2SR,3SR)-3-hydroxy-2-[(1E,4SR)-4-hydroxy-4-methyloct-1-enyl]-5-oxocyclopentyl]heptanoate (.