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: Administration of MK - 801 30 or 60 min after pilocarpine , i . e . , during status epilepticus , gradually reduced electrical and behavioral seizure activity and greatly enhanced the survival rate .
### Output Text:
Administration of <span class="chemical">MK - 801</span> 30 or 60 min after <span class="chemical">pilocarpine</span> , i . e . , during status epilepticus , gradually reduced electrical and behavioral seizure activity and greatly enhanced the survival rate . 