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: Finally , carteolol did not inhibit physostigmine - induced lethality in rats .
### Output Text:
Finally , <span class="chemical">carteolol</span> did not inhibit <span class="chemical">physostigmine</span> - induced lethality in rats . 