Ester (Carboxylic acid derivative) -- ROOR'
Amine -- R-N-R
Ketone -- R-(C=O)-R'
Aldehyde (Carbonyl group) R-(C=O)-H
Thiol -- R-SH
Ether -- R-O-R'
Carboxylic Acid (Carboxyl group) -- RCOOH
Amide (Carboxylic acid derivative) R-C=ON-R'
Alcohol (Hydroxyl group) R-OH
