CAS number： 50-02-2
Molecular formula： C22H29FO5
molecular weight： 392.4611
Chemical structure：
| Product | DEXAMETHASONE BASE | |
| Shelf Life | 5 years | |
| ITEM | SPECIFICATION | RESULT |
| CHARACTER | WHITE OR ALMOST WHITE CRYSTALLINE POWDER | ALMOST WHITE CRYSTALLINE POWDER |
| SPECIFIC ROTATION | +72° TO +80° | +76.2° |
| IDENTIFICATION | （1）COMPLIES BY IR | CONFORMS |
| （2）UV:△E/ERS ≤3.0% | 1.8% | |
| TEST | ||
| CHROMATOGRAPHIC PURITY | PRINCIPAL IMPURITY NOT MORE THAN 1.0% | 0.13% |
| TOTAL IMPURITIES NOT MORE THAN 2.0% | 0.43% | |
| LOSS ON DRYING | NOT MORE THAN 0.5% | 0.09% |
| RESIDUE ON IGNITION | NOT MORE THAN 0.2% | 0.07% |
| RESIDUAL SOLVENT | CHLOROFORM NOT MORE THAN 60ppm | NOT DETECTED |
| METHANOL NOT MORE THAN 1000ppm | 220ppm | |
| ETHYL ACETATE NOT MORE THAN 300ppm | 22ppm | |
| ASSAY | CONTAINS 97.0% TO 102.0% OF C22H29FO5 CALCULATED ON DRIED BASIS | 100.1% |
| CONCLUSION | THE PRODUCT CONFORMS TO USP39 | |
