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: CONCLUSION : In this open trial , galantamine was well - tolerated and appeared to be beneficial for the treatment of interfering behaviors in children with autism , particularly aggression , behavioral dyscontrol , and inattention .
### Output Text:
CONCLUSION : In this open trial , <span class="chemical">galantamine</span> was well - tolerated and appeared to be beneficial for the treatment of interfering behaviors in children with autism , particularly aggression , behavioral dyscontrol , and inattention . 