| Ubrogepant Intermediate 2 | 1455358-06-1 | Ax-URG002 |
| Azelastine EP Impurity B | 117078-69-0 (HCl); 110406-94-5 | Ax-IMP874 |
| Ubrogepant Intermediate 3 | 1235305-63-1 | Ax-URG003 |
| Azelastine EP Impurity D | 53242-89-9; 53242-88-9 | Ax-IMP875 |
| Ubrogepant Intermediate 4 | 1260403-56-2 | Ax-URG004 |
| Azelastine EP Impurity E | 20526-97-0 | Ax-IMP876 |
| Leflunomide EP Impurity C | 61643-23-0 | Ax-IMP869 |
| Ubrogepant Intermediate 6 | 103292-59-7 | Ax-URG006 |
| Ubrogepant Intermediate 7 | 6226-25-1 | Ax-URG007 |
| Leflunomide BP Impurity B | 163451-81-8 | Ax-IMP868 |