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: Neurologic effects of subarachnoid administration of 2 - chloroprocaine - CE , bupivacaine , and low pH normal saline in dogs .
### Output Text:
Neurologic effects of subarachnoid administration of <span class="chemical">2 - chloroprocaine - CE</span> , <span class="chemical">bupivacaine</span> , and low pH normal saline in dogs . 