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: Three infants , born of two mothers with inflammatory bowel disease who received treatment with sulphasalazine throughout pregnancy , were found to have major congenital anomalies .
### Output Text:
Three infants , born of two mothers with inflammatory bowel disease who received treatment with <span class="chemical">sulphasalazine</span> throughout pregnancy , were found to have major congenital anomalies . 