3956
Our results with selective mitogen - activated protein kinase kinase inhibitor 1 , 4 - diamino - 2 , 3 - dicyano - 1 , 4 - bis ( o - aminophenylmercapto ) butadiene monoethanolate ( U0126 ) argues for an important role of extracellular signal - regulated kinase - 1 / 2 pathways activation in PNU - 120596 ' s antinociceptive effects .
 Chemical: 1 , 4 - diamino - 2 , 3 - dicyano - 1 , 4 - bis ( o - aminophenylmercapto ) butadiene monoethanolate; Chemical: U0126; Chemical: PNU - 120596
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: 1 , 4 - diamino - 2 , 3 - dicyano - 1 , 4 - bis ( o - aminophenylmercapto ) butadiene monoethanolate; Chemical: U0126; Chemical: PNU - 120596