Leflunomide
Tier C — Watch / tradeLeflunomide
Targets：DHODH
Brand：Arava, Repso
Indications (approved)：Rheumatoid arthritis, 狼疮肾炎, Psoriatic arthritis
Regional status
Synthetic routes & intermediates6 routes
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.
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-001 | 67305-24-2 | 5-methylisoxazole-4-carbonyl chloride |
| LEFU-002 | 455-14-1 | 4-(trifluoromethyl)aniline |
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-003 | 351-87-1 | 3-oxo-N-(4-(trifluoromethyl)phenyl)butanamide |
| LEFU-004 | 1244971-54-7 | (E)-2-((dimethylamino)methylene)-3-oxo-N-(4-(trifluoromethyl)phenyl)butanamide |
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-001 | 67305-24-2 | 5-methylisoxazole-4-carbonyl chloride |
| LEFU-002 | 455-14-1 | 4-(trifluoromethyl)aniline |
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-002 | 455-14-1 | 4-(trifluoromethyl)aniline |
| LEFU-005 | - | (ethyl carbonic) 5-methylisoxazole-4-carboxylic anhydride |
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-002 | 455-14-1 | 4-(trifluoromethyl)aniline |
| LEFU-006 | 67305-26-4 | (benzyl carbonic) 5-methylisoxazole-4-carboxylic anhydride |
| Code | CAS No. | Intermediate |
|---|---|---|
| LEFU-002 | 455-14-1 | 4-(trifluoromethyl)aniline |
| LEFU-007 | 67305-25-3 | 2,4-dichlorophenyl 5-methylisoxazole-4-carboxylate |
Frequently asked questions
What are the approved indications of Leflunomide?
Approved indications include: Rheumatoid arthritis, 狼疮肾炎, Psoriatic arthritis.
When does the Leflunomide patent expire?
No public expiry year is available for Leflunomide yet; this page updates once verified.
How many synthesis routes are recorded for Leflunomide?
6 synthesis routes are recorded; the shortest is 1 steps with 12.8 g total yield. Intermediates in each route carry codes and CAS numbers.
Where can I buy Leflunomide intermediates?
All intermediates in Leflunomide routes have CAS profiles — you can submit an RFQ per CAS and it enters the Unibest matching pool.
How do I get a quote for Leflunomide 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