26271
Aazahelical chromenes 3 and 4 with varying magnitudes of helicity were designed in pursuit of o - quinonoid intermediates with graded activation barriers .
 Chemical: o - quinonoid
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: o - quinonoid