24482
Two metabolites derived from hydroxylation and one from N - demethylation were also circulating , but were minor , each accounting for < 5 % of plasma radioactivity .
 Chemical: N
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: N