 | C4X-10301 | 774499-89-7 | Impurity | |
| Meptazinol Impurity 1 |
| C4X-10302 | N/A | Impurity | |
| Meptazinol Impurity 2 |
| C4X-10303 | N/A | Impurity | |
| Meptazinol Impurity 3 |
| C4X-10304 | N/A | Impurity | |
| Meptazinol Impurity 4 |
 | C4X-10311 | 190078-45-6 | Impurity | |
| Montelukast EP Impurity A(Sodium Salt) |
| C4X-103110 | 150026-75-8 | Impurity | |
| Montelukast Impurity 10 |
 | C4X-103112 | 807638-71-7 | Impurity | |
| Montelukast Impurity 12 |
 | C4X-103113 | 918972-54-0 | Impurity | |
| Montelukast EP Impurity B |
 | C4X-103114 | 1187586-61-3 | Impurity | |
| Montelukast EP Impurity D |
 | C4X-103115 | 1187586-58-8 | Impurity | |
| Montelukast EP Impurity E |
