8831
In contrast , the pentanoyl and 3 - methylbutanoyl esters were stable .
 Chemical: pentanoyl and 3 - methylbutanoyl esters
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: pentanoyl and 3 - methylbutanoyl esters 
Answer:
 Chemical: pentanoyl and 3 - methylbutanoyl esters