6441
Mass spectrometric data allowed the proposal of two plausible metabolites : 2 , 17 alpha - dimethyl - 16 xi , 17 beta - dihydroxy - 5 alpha - androst - 1 - en - 3 - one ( S1 ) , 2 , 17 alpha - dimethyl - 3 alpha , 16 xi , 17 beta - trihydroxy - 5 alpha - androst - 1 - ene ( S2 ) .
 Chemical: 2 , 17 alpha - dimethyl - 16 xi , 17 beta - dihydroxy - 5 alpha - androst - 1 - en - 3 - one; Chemical: 2 , 17 alpha - dimethyl - 3 alpha , 16 xi , 17 beta - trihydroxy - 5 alpha - androst - 1 - ene
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: 2 , 17 alpha - dimethyl - 16 xi , 17 beta - dihydroxy - 5 alpha - androst - 1 - en - 3 - one; Chemical: 2 , 17 alpha - dimethyl - 3 alpha , 16 xi , 17 beta - trihydroxy - 5 alpha - androst - 1 - ene