21505
In particular , the 2 - pyridinylpiperazinylphenyl substituents provided the resulting chromone derivatives with selective antiviral activity .
 Chemical: 2 - pyridinylpiperazinylphenyl; Chemical: chromone
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 - pyridinylpiperazinylphenyl; Chemical: chromone