Montelukast EP Impurity D; Montelukast USP RC C; Montelukast Bis-Sulfide (Mixture of Diastereomers) ; Montelukast Michael Adduct (R,R)-Isomer

Montelukast EP Impurity D; Montelukast USP RC C; Montelukast Bis-Sulfide (Mixture of Diastereomers) ; Montelukast Michael Adduct (R,R)-Isomer

1-[[[(1R)-1-[3-[(1R)-1-[[[1-(Carboxymethyl)cyclopropyl]methyl]thio]-2-(7-chloro-2-quinolinyl)ethyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl) phenyl] propyl] thio]methyl]-cyclopropaneacetic acid

Impurity reference standard used for related substances testing of Montelukast Acid drug substance and drug product per pharmacopoeial limits.