21152
Compounds bearing this conformation participated in a favorable hydrophobic interaction with a cysteine residue in the JAK3 binding pocket , which imparted high selectivity versus the kinome and improved selectivity within the JAK family .
 Chemical: cysteine
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: cysteine