[chemical substances]
   compounds
     Class amides [RkE(=O)l(OH)m (l≠0; ≥1 (OH):=(NR2))]
       1 Class primary amides [acyl-NR2]
       2 Class secondary amides [acyl2-NR]
       3 Class tertiary amides [acyl3-N]
       4 Class anilides [RkE(=O)l(OH)m (l≠0; ≥1 (OH):=(NHPh))]