Reference Standard
| CAS Number | Not assigned |
| Formula | Approx. C₄₄H₆₆N₂O₁₄ |
| Molecular Weight | ~850 g/mol |
| Purity | ≥95% |
| Storage | Store at −20 °C; protect from light and moisture |
A nitrosated derivative of the tacrolimus 21-carboxylic acid impurity, monitored due to regulatory concern regarding nitroso compounds.
Used in nitrosamine risk assessment, impurity identification, and method validation for tacrolimus.
Characterized by LC-MS/MS, HPLC, NMR, and trace-level impurity analysis.
