29370
This study investigated the structural requirements within protoporphyrin IX ( PPIX ) for the inhibition of HSP90 activity .
 Chemical: protoporphyrin IX; Chemical: PPIX
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: protoporphyrin IX; Chemical: PPIX