29036
Boronated nucleosides developed prior to 3CTAs for BNCT and non - boronated N3 - substituted thymidine conjugates for other areas of cancer therapy and imaging are also described .
 Chemical: N3 - substituted thymidine
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: N3 - substituted thymidine 
Answer:
 Chemical: N3 - substituted thymidine