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: The most common side effects attributable to the AraG included Grade 2 and 3 sensory and motor neuropathy and musculoskeletal pain .
### Output Text:
The most common side effects attributable to the <span class="chemical">AraG</span> included Grade 2 and 3 sensory and motor neuropathy and musculoskeletal pain . 