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: Methoxamine evoked non - significant increases in MUP and diastolic blood pressure but caused a significant rise in systolic blood pressure and significant fall in heart rate at maximum dosage .
### Output Text:
<span class="chemical">Methoxamine</span> evoked non - significant increases in MUP and diastolic blood pressure but caused a significant rise in systolic blood pressure and significant fall in heart rate at maximum dosage . 