28882
We have designed the cyclopropane analog of stilbene as subtype - selective ligands for estrogen receptor based on the bioisosterism that cyclopropane could act as alkene bioisoster .
 cyclopropane, stilbene, estrogen, cyclopropane, alkene
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 cyclopropane, stilbene, estrogen, cyclopropane, alkene