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: In a 12 - week controlled study ethopropazine was compared to benztropine in the treatment of parkinsonism induced by fluphenazine enanthate in 60 schizophrenic outpatients .
### Output Text:
In a 12 - week controlled study <span class="chemical">ethopropazine</span> was compared to <span class="chemical">benztropine</span> in the treatment of parkinsonism induced by <span class="chemical">fluphenazine enanthate</span> in 60 schizophrenic outpatients . 