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: Although both dl - sotalol and azimilide rarely induced EADs in canine left ventricles , they produced frequent EADs in rabbits , in which more pronounced QT prolongation was seen .
### Output Text:
Although both dl - <span class="chemical">sotalol</span> and <span class="chemical">azimilide</span> rarely induced EADs in canine left ventricles , they produced frequent EADs in rabbits , in which more pronounced QT prolongation was seen . 