20921
Herein we report a modified synthesis of a known RAR alpha antagonist , 2 - fluoro - 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid and a synthesis of its unknown , desfluoro analog , 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid .
 Chemical: 2 - fluoro - 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid; Chemical: 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: 2 - fluoro - 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid; Chemical: 4 - [ [ [ 8 - bromo - 2 , 2 - dimethyl - 4 - ( 4 - methylphenyl ) chroman - 6 - yl ] carbonyl ] amino ] benzoic acid