| Upadacitinib Intermediate 1 | NA | Ax-ABT01 |
| Lenalidomide Process Impurity 5 | 17191-52-5 | Ax-IMP1420 |
| Upadacitinib Intermediate 2 | NA | Ax-ABT02 |
| Lenalidomide Process Impurity 6 | NA | Ax-IMP1421 |
| Upadacitinib Intermediate 3 | NA | Ax-ABT03 |
| Lenalidomide Process Impurity 7 | NA | Ax-IMP1422 |
| Upadacitinib Intermediate 4 | NA | Ax-ABT04 |
| Lenalidomide Process Impurity 8 | 1198299-72-7 | Ax-IMP1423 |
| Upadacitinib Intermediate 5 | NA | Ax-ABT-05 |
| Lenalidomide N-oxide impurity | NA | Ax-IMP1430 |