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: Our patients developed jaundice following treatment with ticlopidine and showed the clinical and laboratory characteristics of cholestatic hepatitis , which resolved after discontinuation of the drug .
### Output Text:
Our patients developed jaundice following treatment with <span class="chemical">ticlopidine</span> and showed the clinical and laboratory characteristics of cholestatic hepatitis , which resolved after discontinuation of the drug . 