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: This was the second report of fatal aplastic anemia after topical treatment with chloramphenicol for ocular conditions , although two cases of reversible bone marrow hypoplasia have also been reported .
### Output Text:
This was the second report of fatal aplastic anemia after topical treatment with <span class="chemical">chloramphenicol</span> for ocular conditions , although two cases of reversible bone marrow hypoplasia have also been reported . 