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: OBJECTIVE : To report a case of a severe interaction between simvastatin , amiodarone , and atazanavir resulting in rhabdomyolysis and acute renal failure .
### Output Text:
OBJECTIVE : To report a case of a severe interaction between <span class="chemical">simvastatin</span> , <span class="chemical">amiodarone</span> , and <span class="chemical">atazanavir</span> resulting in rhabdomyolysis and acute renal failure . 