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 daidzein ( 4 . 5 mg / kg body weight ) to mice was shown significantly to reverse scopolamine - induced amnesia , according to the results of a Y - maze test .
### Output Text:
Administration of <span class="chemical">daidzein</span> ( 4 . 5 mg / kg body weight ) to mice was shown significantly to reverse <span class="chemical">scopolamine</span> - induced amnesia , according to the results of a Y - maze test . 