2933: Heterocyclics, nitrogen hetero atom only, nucleic aci

293311: Phenazone (antipyrin), derivatives 293319: Heterocyclic compounds with unfused pyrazole ring, ne 293321: Hydantoin, derivatives 293329: Heterocyclic compounds with unfused imidazole ring,ne 293331: Pyridine, salts 293339: Heterocyclic compounds with unfused pyridine ring,nes 293340: Heterocyc cmpounds, quinoline ring not further fused 293351: Barbituric acid, derivatives, salts thereof 293359: Hetercyclic compounds with pyrimidine ring nes 293361: Melamine 293369: Heterocyclic compds with an unfused triazine ring nes 293371: 6-hexanelactam (epsilon-captolactam) 293379: Lactams other than 6-hexanelactam 293390: Heterocyclic compounds with N-hetero-atom(s) only, ne 2933: Heterocyclics, nitrogen hetero atom only, nucleic aci