7601
Based on structure - activity relationship studies of the benzoic acid part of diphenylamine - based retinoids , the potent RXR agonist 4 was derivatized to obtain retinoid agonists , synergists , and an antagonist .
 Chemical: benzoic acid; Chemical: diphenylamine; Chemical: retinoids; Chemical: retinoid
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: benzoic acid, diphenylamine, retinoids, retinoid 
Answer:
 Chemical: benzoic acid; Chemical: diphenylamine; Chemical: retinoids; Chemical: retinoid