1799
Specific alkylating molecules were synthesized and the crystal structures of the complexes they form with soman - aged human butyrylcholinesterase were solved .
 Chemical: soman
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: soman 
Answer:
 Chemical: soman