24252
Structure - activity relationship study indicates that introducing substituent in phenyl ring or replacing phenyl ring by pyridine / naphthalene , or decreasing the ring size of lactones ( from six to five member ) do not increase the cytotoxicity .
 Chemical: phenyl; Chemical: pyridine; Chemical: naphthalene; Chemical: lactones
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: phenyl; Chemical: pyridine; Chemical: naphthalene; Chemical: lactones