← Back to patent-cliff list
Montelukast
Tier B — Position earlyMontelukast
Merck & Co Inc
Originator
1997
First approval
-
Expiry (public)
$5.96B ▲
Peak sales
Small molecule
Type
Targets：CYSLTR1
Brand：Kipres, Singulair
Indications (approved)：Allergic rhinitis, Asthma, Hypersensitivity reaction, Seasonal allergic rhinitis, Perennial allergic rhinitis, Exercise-induced asthma
Regional status
US
Approved
1998-02-20
EU
Discontinued
2005-09-01
China
Approved
1999-10-29
Japan
Approved
2001-06-20
Factories producing this API1
Factories registered as producing this API in our sourcing network (RFQ records + product master), sorted by RFQ activity; the snapshot carries no cost or customer data.
1 producing factories on file — sign in to view the named list (factory details are not shown to guests).
Sign in to view factories →Synthetic routes & intermediates5 routes
Originator routes × 1Optimised (non-patent) × 3Process routes × 1
Routes are ordered originator first, then optimised / process (non-patent) routes; each lists steps, overall yield and the intermediate table (code / CAS / name) — ready for supplier sourcing and RFQ. Rendered by this site from structured data; no third-party route graphics used.
OriginatorRoute 1Steps 15 · Total yield /
MONT-0014965-33-7MONT-002626-19-7MONT-003115104-40-0MONT-004142569-55-9MONT-005610-94-6MONT-006133791-17-0MONT-007142569-69-5MONT-008142569-70-8MONT-009142542-53-8MONT-010162489-71-6MONT-011142148-14-9MONT-0121000788-70-4MONT-013110-86-1MONT-014158966-92-8MONT-0151559-02-0MONT-01639590-81-3MONT-017142148-11-6MONT-018142148-12-7MONT-019869066-83-1API · Montelukast
| Code | CAS No. | Intermediate |
|---|---|---|
| MONT-001 | 4965-33-7 | 7-chloro-2-methylquinoline |
| MONT-002 | 626-19-7 | isophthalaldehyde |
| MONT-003 | 115104-40-0 | (E)-3-(2-(7-chloroquinolin-2-yl)vinyl)benzaldehyde |
| MONT-004 | 142569-55-9 | (E)-1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)prop-2-en-1-ol |
| MONT-005 | 610-94-6 | methyl 2-bromobenzoate |
| MONT-006 | 133791-17-0 | methyl (E)-2-(3-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-oxopropyl)benzoate |
| MONT-007 | 142569-69-5 | methyl (S,E)-2-(3-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-hydroxypropyl)benzoate |
| MONT-008 | 142569-70-8 | (S,E)-1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propan-1-ol |
| MONT-009 | 142542-53-8 | (1S)-1-(3-((E)-2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-((tetrahydro-2H-pyran-2-yl)oxy)propan-2-yl)phenyl)propan-1-ol |
| MONT-010 | 162489-71-6 | (1S)-1-(3-((E)-2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-((tetrahydro-2H-pyran-2-yl)oxy)propan-2-yl)phenyl)propyl methanesulfonate |
| MONT-011 | 142148-14-9 | methyl 2-(1-((acetylthio)methyl)cyclopropyl)acetate |
| MONT-012 | 1000788-70-4 | methyl 2-(1-((((1R)-1-(3-((E)-2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-((tetrahydro-2H-pyran-2-yl)oxy)propan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetate |
| MONT-013 | 110-86-1 | pyridine |
| MONT-014 | 158966-92-8 | (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetic acid |
| MONT-015 | 1559-02-0Available | diethyl cyclopropane-1,1-dicarboxylate |
| MONT-016 | 39590-81-3 | cyclopropane-1,1-diyldimethanol |
| MONT-017 | 142148-11-6 | (1-(hydroxymethyl)cyclopropyl)methyl benzoate |
| MONT-018 | 142148-12-7 | (1-(cyanomethyl)cyclopropyl)methyl benzoate |
| MONT-019 | 869066-83-1 | 2-(1-(hydroxymethyl)cyclopropyl)acetic acid |
OptimisedRoute 3Steps 5 · Total yield 33.50 g
MONT-014158966-92-8MONT-023855473-48-2MONT-0241399184-57-6MONT-025855473-50-6MONT-026855473-51-7MONT-027—API · Montelukast
| Code | CAS No. | Intermediate |
|---|---|---|
| MONT-014 | 158966-92-8 | (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetic acid |
| MONT-023 | 855473-48-2 | methyl (R,E)-2-(3-(acetylthio)-3-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)propyl)benzoate |
| MONT-024 | 1399184-57-6 | (R,E)-2-(2-(3-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-mercaptopropyl)phenyl)propan-2-ol ((4R)-7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl)methanesulfonate |
| MONT-025 | 855473-50-6 | methyl 2-(1-(bromomethyl)cyclopropyl)acetate |
| MONT-026 | 855473-51-7 | methyl (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetate |
| MONT-027 | - | diisobutylamine 2-(1-((((R)-1-(3-((E)-2-((E)-6-(2-chloroethylidene)-5,6-dihydropyridin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetate |
OptimisedRoute 4Steps 10 · Total yield /
MONT-014158966-92-8MONT-0283132-99-8MONT-02958824-55-8MONT-030610-97-9MONT-031165896-48-0MONT-032165896-49-1MONT-033762273-01-8MONT-034866923-64-0MONT-0351433669-59-0MONT-036177748-00-4MONT-037866923-62-8MONT-03859394-27-3API · Montelukast
| Code | CAS No. | Intermediate |
|---|---|---|
| MONT-014 | 158966-92-8 | (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetic acid |
| MONT-028 | 3132-99-8 | 3-bromobenzaldehyde |
| MONT-029 | 58824-55-8 | 1-(3-bromophenyl)prop-2-en-1-ol |
| MONT-030 | 610-97-9 | methyl 2-iodobenzoate |
| MONT-031 | 165896-48-0 | methyl 2-(3-(3-bromophenyl)-3-oxopropyl)benzoate |
| MONT-032 | 165896-49-1 | methyl (S)-2-(3-(3-bromophenyl)-3-hydroxypropyl)benzoate |
| MONT-033 | 762273-01-8 | (S)-1-(3-bromophenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propan-1-ol |
| MONT-034 | 866923-64-0 | 2-(1-(mercaptomethyl)cyclopropyl)acetonitrile |
| MONT-035 | 1433669-59-0 | (R)-2-(1-(((1-(3-bromophenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetonitrile |
| MONT-036 | 177748-00-4 | 7-chloro-2-vinylquinoline |
| MONT-037 | 866923-62-8 | (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetonitrile |
| MONT-038 | 59394-27-3 | 7-chloroquinoline-2-carbaldehyde |
OptimisedRoute 5Steps 7 · Total yield /
MONT-03999-04-7MONT-04099-36-5MONT-0411129-28-8MONT-042—MONT-0014965-33-7MONT-043—MONT-044—MONT-045—MONT-0466148-64-7API · Montelukast
| Code | CAS No. | Intermediate |
|---|---|---|
| MONT-039 | 99-04-7 | 3-Methylbenzoic acidm-Toluic acid |
| MONT-040 | 99-36-5 | 3-Methylbenzoic acid methyl ester |
| MONT-041 | 1129-28-8 | methyl 3-(bromomethyl)benzoate |
| MONT-042 | - | 3-[(E)-2-(7-Chloroquinolin-2-yl)ethenyl]benzoic acid methyl ester |
| MONT-001 | 4965-33-7 | 7-Chloro-2-methylquinoline 7-Chloroquinaldine |
| MONT-043 | - | 3-[(E)-2-(7-Chloroquinolin-2-yl)ethenyl]benzoic acid methyl ester |
| MONT-044 | - | 3-[(E)-2-(7-Chloroquinolin-2-yl)ethenyl]benzoic acid |
| MONT-045 | - | 3-[(E)-2-(7-Chloroquinolin-2-yl)ethenyl]benzoyl chloride |
| MONT-046 | 6148-64-7Available | potassium 3-ethoxy-3-oxopropanoate |
ProcessRoute 2Steps 4 · Total yield 1.09 kg
MONT-008142569-70-8MONT-020169954-93-2MONT-021162515-68-6MONT-022851755-58-3crude Montelukast Sodium151767-02-1API · Montelukast
| Code | CAS No. | Intermediate |
|---|---|---|
| MONT-008 | 142569-70-8 | (S,E)-1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propan-1-ol |
| MONT-020 | 169954-93-2 | (S,E)-1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl methanesulfonate |
| MONT-021 | 162515-68-6 | 2-(1-(mercaptomethyl)cyclopropyl)acetic acid |
| MONT-022 | 851755-58-3 | propan-2-amine (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetate |
| crude Montelukast Sodium | 151767-02-1 | sodium (R,E)-2-(1-(((1-(3-(2-(7-chloroquinolin-2-yl)vinyl)phenyl)-3-(2-(2-hydroxypropan-2-yl)phenyl)propyl)thio)methyl)cyclopropyl)acetate |
Frequently asked questions
What are the approved indications of Montelukast?
Approved indications include: Allergic rhinitis, Asthma, Hypersensitivity reaction, Seasonal allergic rhinitis, Perennial allergic rhinitis, Exercise-induced asthma.
When does the Montelukast patent expire?
No public expiry year is available for Montelukast yet; this page updates once verified.
How many synthesis routes are recorded for Montelukast?
5 synthesis routes are recorded; the shortest is 4 steps with 1.09 kg total yield. Intermediates in each route carry codes and CAS numbers.
Where can I buy Montelukast intermediates?
2 intermediate CAS of Montelukast are available through the Unibest supply network — see the route tables on this page and request a quote per CAS.
How do I get a quote for Montelukast intermediates?
Open the CAS profile of the target intermediate from this page, or submit an RFQ directly — the CAS enters the matching flow automatically and the supply network responds with quotes.
Source: cross-verified data (structured fields only) · 2026-09-29