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: ( RS ) - 1 - aminoindan - 1 , 5 - dicarboxylic acid ( AIDA ; 0 . 5 - 15 microg / 0 . 5 microl ) , a potent and selective mGluR1 antagonist , or ( 2R , 4R ) - 4 - aminopyrrolidine - 2 , 4 - dicarboxylate ( 2R , 4R - APDC ; 7 . 5 - 15 microg / 0 . 5 microl ) , a selective group II agonist , was injected bilaterally into the striatum of haloperidol - treated animals .
### Output Text:
<span class="chemical">( RS ) - 1 - aminoindan - 1 , 5 - dicarboxylic acid</span> ( <span class="chemical">AIDA</span> ; 0 . 5 - 15 microg / 0 . 5 microl ) , a potent and selective mGluR1 antagonist , or <span class="chemical">( 2R , 4R ) - 4 - aminopyrrolidine - 2 , 4 - dicarboxylate</span> ( <span class="chemical">2R , 4R - APDC</span> ; 7 . 5 - 15 microg / 0 . 5 microl ) , a selective group II agonist , was injected bilaterally into the striatum of <span class="chemical">haloperidol</span> - treated animals . 