21091
The absolute configurations of 1 - 4 were assigned by the modified Mosher ' s method and TDDFT ECD calculations together with comparison of their CD spectra .
 None
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:  
Answer:
 None