23188
Compounds 6a , 6b , 8a , 8b , 9a , 9b , 10a and 10b were proved to be potent COX - 2 inhibitors with IC50 range of 0 . 1 - 4 . 0 mu M .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None