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: Two recently available immunosuppressive agents , mycophenolate mofetil and sirolimus ( rapamycin ) , have no nephrotoxicity .
### Output Text:
Two recently available immunosuppressive agents , <span class="chemical">mycophenolate mofetil</span> and <span class="chemical">sirolimus</span> ( <span class="chemical">rapamycin</span> ) , have no nephrotoxicity . 