12941
Compound 9 , designated as phorbin A , has a monocyclic structure and is proposed to be a possible biogenetic precursor of the phorbaketals .
 Chemical: phorbin A; Chemical: phorbaketals
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: phorbin A; Chemical: phorbaketals