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: Effects of amine pretreatment on ketamine catatonia in pinealectomized or hypophysectomized animals .
### Output Text:
Effects of <span class="chemical">amine</span> pretreatment on <span class="chemical">ketamine</span> catatonia in pinealectomized or hypophysectomized animals . 