21608
A novel series of histone deacetylase inhibitors combining N - hydroxycinnamamide bioactive fragment and indole bioactive fragment was designed and synthesized .
 N - hydroxycinnamamide, indole
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 N - hydroxycinnamamide, indole