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: By multivariate analysis , in both the placebo and enalapril groups older age , diuretic therapy , and diabetes were associated with decreased renal function , whereas beta - blocker therapy and higher ejection fraction were renoprotective .
### Output Text:
By multivariate analysis , in both the placebo and <span class="chemical">enalapril</span> groups older age , <span class="chemical">diuretic</span> therapy , and diabetes were associated with decreased renal function , whereas beta - blocker therapy and higher ejection fraction were renoprotective . 