In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The possibility of de novo glomerular pathology under SRL treatment requires further investigation by renal biopsy .
### Output Text:
The possibility of de novo glomerular pathology under <span class="chemical">SRL</span> treatment requires further investigation by renal biopsy . 