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: We report a case of methyldopa - induced hemolytic anemia in a 15 - year - old boy who presented to the emergency department with near - syncope .
### Output Text:
We report a case of <span class="chemical">methyldopa</span> - induced hemolytic anemia in a 15 - year - old boy who presented to the emergency department with near - syncope . 