12213
For the search of new anti - HBV agents , much investigation has revealed a large number of small - molecule compounds with various skeletons and promising anti - HBV activities .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None