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: CONCLUSIONS : Initiating treatment of type 2 diabetes with glibenclamide or glipizide is associated with increased risk of CAD in comparison to gliclazide or glimepiride .
### Output Text:
CONCLUSIONS : Initiating treatment of type 2 diabetes with <span class="chemical">glibenclamide</span> or <span class="chemical">glipizide</span> is associated with increased risk of CAD in comparison to <span class="chemical">gliclazide</span> or <span class="chemical">glimepiride</span> . 