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 also examined the neuroprotective effects of maltolyl p - coumarate in vitro using SH - SY5Y cells .
### Output Text:
We also examined the neuroprotective effects of <span class="chemical">maltolyl p - coumarate</span> in vitro using SH - SY5Y cells . 