20941
This paper describes a novel series of N , O - acetals and N , S - acetals ( 7a - o ) derived from 2 - amino - 1 , 4 - naphthoquinones that were synthesized and evaluated as potential antimicrobial agents .
 Chemical: N , O - acetals; Chemical: N , S - acetals; Chemical: 2 - amino - 1 , 4 - naphthoquinones
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 , O - acetals; Chemical: N , S - acetals; Chemical: 2 - amino - 1 , 4 - naphthoquinones