6962
This was done by introduction of a heteroatom ( N or O ) in alpha - position to the phosphonate and using the resultant OH and NH 2 groups as a handle for appending a variety of substituents by means of several functional groups such as ether , amide , urea , and 1 , 4 - triazole .
 Chemical: N; Chemical: O; Chemical: phosphonate; Chemical: OH; Chemical: NH 2; Chemical: ether; Chemical: amide; Chemical: urea; Chemical: 1 , 4 - triazole
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; Chemical: O; Chemical: phosphonate; Chemical: OH; Chemical: NH 2; Chemical: ether; Chemical: amide; Chemical: urea; Chemical: 1 , 4 - triazole