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: Paclitaxel ( Taxol ; Bristol - Myers Squibb Company , Princeton , NJ ) by 3 - hour infusion was combined with carboplatin in a phase I / II study directed to patients with non - small cell lung cancer .
### Output Text:
<span class="chemical">Paclitaxel</span> ( <span class="chemical">Taxol</span> ; Bristol - Myers Squibb Company , Princeton , NJ ) by 3 - hour infusion was combined with <span class="chemical">carboplatin</span> in a phase I / II study directed to patients with non - small cell lung cancer . 