Subject
heterocyclic compound
15
hydroxyl group
organic compound
amine
7
carbonyl group
5
carboxylic acid
5
carbonyl compound
4
ketone
4
carboxyl group
3
carboxylate
3
hydroxylamine
3
carboxylic acid ester
2
hydrazine
2
sulfonic acid
2
azo compound
1
carboxylation
1
hydroxylation
1
nitroso compound
1
triazine
1