Subject
carboxyl group
heterocyclic compound
9
carboxylate
8
carboxylic acid
8
carboxylic acid ester
7
organic compound
7
hydroxyl group
3
acid
2
carbonyl compound
2
carbonyl group
2
carboxylation
2
sulfonic acid
2
amine
1
azo compound
1
hydrazine
1
hydroxylamine
1
hydroxylation
1
nitrosamine
1
nitroso compound
1