6331
Electronic transition moments of 6 - methyl isoxanthopterin - - a fluorescent analogue of the nucleic acid base guanine .
 Chemical: 6 - methyl isoxanthopterin; Chemical: guanine
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: 6 - methyl isoxanthopterin; Chemical: guanine