21618
Four dimeric sterol - polyamine conjugates have been synthesized from the homo - and hetero - connection of monomeric sterol - polyamine analogs in a head - to - tail manner .
 Chemical: sterol; Chemical: polyamine; Chemical: sterol; Chemical: polyamine
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: sterol; Chemical: polyamine; Chemical: sterol; Chemical: polyamine