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: In this small patient sample , liposomal daunorubicin was an effective and well tolerated agent in the treatment of Kaposi ' s sarcoma .
### Output Text:
In this small patient sample , liposomal <span class="chemical">daunorubicin</span> was an effective and well tolerated agent in the treatment of Kaposi ' s sarcoma . 