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: Enalapril treatment blunted but did not prevent reduction in GFR in group 4 ( 0 . 86 + / - 0 . 15 ml / min at 4 months , 0 . 69 + / - 0 . 13 ml / min at 6 months , both P less than 0 . 05 vs . group 3 ) .
### Output Text:
<span class="chemical">Enalapril</span> treatment blunted but did not prevent reduction in GFR in group 4 ( 0 . 86 + / - 0 . 15 ml / min at 4 months , 0 . 69 + / - 0 . 13 ml / min at 6 months , both P less than 0 . 05 vs . group 3 ) . 