14638
Kinase selectivity profiling of ( R ) - and ( S ) - enantiomers 16e and 16g , respectively , revealed that introduction of a guanidino group at the C6 position of the purine moiety decreased selectivity towards protein kinases compared to roscovitine .
 Chemical: guanidino; Chemical: purine; Chemical: roscovitine
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: guanidino; Chemical: purine; Chemical: roscovitine