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: To best of our knowledge this is the second case of fatal carbamazepine induced myocarditis reported in English literature .
### Output Text:
To best of our knowledge this is the second case of fatal <span class="chemical">carbamazepine</span> induced myocarditis reported in English literature . 