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: A case of triamterene nephrolithiasis is reported in a man after 4 years of hydrochlorothiazide - triamterene therapy for hypertension .
### Output Text:
A case of <span class="chemical">triamterene</span> nephrolithiasis is reported in a man after 4 years of <span class="chemical">hydrochlorothiazide - triamterene</span> therapy for hypertension . 