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: AIMS : This study sought to assess the risk of developing coronary artery disease ( CAD ) associated with initial treatment of type 2 diabetes with different sulphonylureas .
### Output Text:
AIMS : This study sought to assess the risk of developing coronary artery disease ( CAD ) associated with initial treatment of type 2 diabetes with different <span class="chemical">sulphonylureas</span> . 