| ITEM | STANDARD |
| Appearance | Yellow or orange crystalline powder.almostodourless |
| IdentificationUltraviolet AbsorptionA256/A365 | Between 2.80 and 3.00 |
| Water | Not more than 8.5% |
| Chromatographic purity | Not greater than 2.0 % |
| Organic volatile impurities | Meet the requirements |
| Assay | 97.0~102.0% |