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: Incubation with NS - 718 resulted in significantly less damage of cultured human renal proximal tubular epithelial cells compared with D - AmB .
### Output Text:
Incubation with NS - 718 resulted in significantly less damage of cultured human renal proximal tubular epithelial cells compared with <span class="chemical">D - AmB</span> . 