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: Bepridil , a novel active compound for prophylactic treatment of anginal attacks , induced persistent bradycardia and a non - specific anti - tachycardial effect , the mechanisms of which were investigated in vitro and in vivo .
### Output Text:
<span class="chemical">Bepridil</span> , a novel active compound for prophylactic treatment of anginal attacks , induced persistent bradycardia and a non - specific anti - tachycardial effect , the mechanisms of which were investigated in vitro and in vivo . 