6890
Modifications at the 7 - position of the 4 - azaindole core modulated potency significantly and SAR showed that certain compounds with a 5 - membered ring heteroaryl group at that position were the most potent .
 Chemical: 4 - azaindole
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 - azaindole