MTL01: Montelukast (Acid)

1-[1-[[[(1R)-1-[3-[(1E)-2-(7-Chloro-2-quinolinyl)ethenyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid
[CAS # 158966-92-8]

MTL02: Montelukast Sodium [CAS # 151767-02-1]

MTL03: 2-(2-(3S-(2-(7-chloro-2-quinolinyl)- ethenyl-phenyl)-3-hydroxy-propyl)phenyl)-2-propanol
[CAS # 142569-70-8]

MTL04: 3-(Mercaptomethyl)cyclopropane acetic acid [ CAS # 162515-68-6 ]

MTL05: 2-(3S-(2-(7-chloro-2-quinolinyl)-ethenyl-phenyl)-3-hydroxy-propyl)-1-methoxycarbonylbenzene
[CAS # 142569-69-5; 181139-72-0]

MTL06: 2-(3-(2-(7-chloro-2-quinolinyl)-ethenyl-phenyl)-3-oxo-propyl)-1-methoxycarbonylbenzene
[CAS # 133791-17-0; 149968-11-6]

MTL07: Montelukast Sulfoxide

Synonym: Montelukast EP Impurity C (= USP Impurity A) ; Montelukast S-Oxide

CAS Name: [1-[[[1-[3-[(E)-2-(7-chloroquinolin-2-yl)ethenyl]phenyl]-3-[2-(2-hydrox-ypropan-2-yl)phenyl]propyl]sulfinyl]methyl]cyclopropyl]acetic acid.
[CAS # 909849-96-3]

MTL08: Montelukast Sulfone

MTL09: Montelukast cis Isomer

Synonym: Montelukast EP Impurity G (= USP Impurity B)

CAS Name: [1-[[[(1R)-1-[3-[(Z)-2-(7-chloroquinolin-2-yl)ethenyl]phenyl]-3-[2-(2-hydroxypropan- 2-yl)phenyl]propyl]sulfanyl]methyl]cyclopropyl]acetic acid.
[CAS # 774538-96-4]

MTL10: Montelukast Methylketone Impurity

Synonym: Montelukast EP Impurity F (= USP Impurity E)

CAS Name: [1-[[[(1R)-3-(2-acetylphenyl)-1-[3-[(E)-2-(7-chloroquinolin-2- yl)ethenyl]phenyl]propyl]sulfanyl]methyl]cyclopropyl]acetic acid.
[CAS # 937275-23-5]

MTL11: Montelukast Methylstyrene Impurity

Synonym: Montelukast EP Impurity B (= USP Impurity F)

CAS Name: [1-[[[(1R)-1-[3-[(E)-2-(7-chloroquinolin-2-yl)ethenyl]phenyl]-3-[2-(prop-1-en-2- yl)phenyl]propyl]sulfanyl]methyl]cyclopropyl]acetic acid.
[CAS # 918972-54-0]

MTL12: Montelukast 1,2-Diol

1-[1-[[[(1R)-1-[3-[(1E)-2-(7-Chloro-2-quinolinyl)ethenyl]phenyl]-3-[2-(1,2-diol-2-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid
[CAS # 186352-97-6]

MTL13: Montelukast Disulfide Impurity

MTL14: Montelukast Ether Impurity [CAS # 168214-67-3]

MTL15: Montelukast Dicyclohexylamine [CAS # 577953-88-9]

MTL16: Montelukast Dihydro Impurity

(1R)-1-[[[1-[3-[2-(7-Chloro-2-quinolinyl)ethyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid
[CAS # 142147-98-6 for sodium salt]

MTL17: Montelukast Lactone

MTL18: Montelukast Michael Adduct R,R-Isomer

Synonyms: Montelukast EP Impurity D (= USP Impurity C)

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

MTL19: Montelukast Michael Adduct R,S-Isomer

Synonyms: Montelukast EP Impurity E (= USP Impurity D)

1-[[[(1R)-1-[3-[(1S)-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

MTL20: Montelukast Sodium Racemate

1-[1-[[[(1RS)-1-[3-[(1E)-2-(7-Chloro-2-quinolinyl)ethenyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid sodium salt

MTL21: Montelukast Sodium S-Isomer

Synonym: Montelukast Sodium EP Impurity A

1-[1-[[[(1S)-1-[3-[(1E)-2-(7-Chloro-2-quinolinyl)ethenyl]phenyl]-3-[2-(1-hydroxy-1-methylethyl)phenyl]propyl]thio]methyl]cyclopropaneacetic acid sodium salt
[CAS # 190078-45-6]