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 acute renal dysfunction associated with sirolimus ( such as in delayed graft function ) may be due to suppression of compensatory renal cell proliferation and survival / repair processes .
### Output Text:
The acute renal dysfunction associated with <span class="chemical">sirolimus</span> ( such as in delayed graft function ) may be due to suppression of compensatory renal cell proliferation and survival / repair processes . 