7795
Although not the most active , 4 - NH ( 2 ) substituted compounds possessed the lowest in vitro cytotoxicity ( hepatotoxicity ) , leading to selectivity index SI = 5 . 5 and SI > 21 .
 Chemical: 4 - NH ( 2 )
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: 4 - NH ( 2 )