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: We treated 38 patients ( 22 low renin , 16 normal renin ) with moderate diastolic hypertension with hydrochlorothiazide ( HCTC ) administered on a twice daily schedule .
### Output Text:
We treated 38 patients ( 22 low renin , 16 normal renin ) with moderate diastolic hypertension with <span class="chemical">hydrochlorothiazide</span> ( <span class="chemical">HCTC</span> ) administered on a twice daily schedule . 