| 293311 | Heterocyclic compounds; with nitrogen hetero-atom(s) only, containing an unfused pyrazole ring (whether or not hydrogenated) in the structure, phenazone (antipyrin) and its derivatives | 3.25% (2023 MFN average)WITS 2023 historical MFN average |
| 293319 | Heterocyclic compounds; with nitrogen hetero-atom(s) only, containing an unfused pyrazole ring (whether or not hydrogenated) in the structure, other than henazone (antipyrin) and its derivatives | 3.25% (2023 MFN average)WITS 2023 historical MFN average |
| 293329 | Heterocyclic compounds; with nitrogen hetero-atom(s) only, containing an unfused imidazole ring (whether or not hydrogenated) in the structure, other than hydantoin and its derivatives | 3.25% (2023 MFN average)WITS 2023 historical MFN average |
| 293331 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, pyridine and its salts | 5.30% (2023 MFN average)WITS 2023 historical MFN average |
| 293332 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, piperidine and its salts | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293333 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, alfentanil (INN), anileridine (INN), bezitramide (INN), bromazepam (INN), carfentanil (INN), difenoxin (INN), diphenoxylate (INN), dipipanone (INN) | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293334 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, other fentanyls and their derivatives | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293335 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, 3-quinuclidinol | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293336 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, 4-anilino-N-phenethylpiperidine (ANPP) | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293337 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, N-phenethyl-4-piperdone (NPP) | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293339 | Heterocyclic compounds; containing an unfused pyridine ring (whether or not hydrogenated) in the structure, n.e.c. in 2933.3 | 1.17% (2023 MFN average)WITS 2023 historical MFN average |
| 293341 | Heterocyclic compounds; containing a quinoline or isoquinoline ring-system (whether or not hydrogenated) in the structure, not further fused, levorphanol (INN) and its salts | 0.00% (2023 MFN average)WITS 2023 historical MFN average |
| 293349 | Heterocyclic compounds; containing a quinoline or isoquinoline ring-system (whether or not hydrogenated) in the structure, not further fused, other than levorphanol (INN) and its salts | 4.00% (2023 MFN average)WITS 2023 historical MFN average |
| 293352 | Heterocyclic compounds; containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, malonylurea (barbituric acid) and its salts | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293353 | Allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof | 3.25% (2023 MFN average)WITS 2023 historical MFN average |
| 293354 | Heterocyclic compounds; containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, other derivatives of malonylurea (barbituric acid) and salts thereof, n.e.c. in 2933.53 | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293355 | Heterocyclic compounds; containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure; loprazolam (INN), mecloqualone (INN), methaqualone (INN), and zipeprol (INN); salts thereof | 0.00% (2023 MFN average)WITS 2023 historical MFN average |
| 293359 | Heterocyclic compounds; containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, (other than malonylurea and its derivatives, loprazolam, mecloqualone, methaqualone, zipeprol, and salts thereof) n.e.c. in 2933.5 | 2.17% (2023 MFN average)WITS 2023 historical MFN average |
| 293361 | Heterocyclic compounds; containing an unfused triazine ring (whether or not hydrogenated) in the structure, melamine | 6.50% (2023 MFN average)WITS 2023 historical MFN average |
| 293369 | Heterocyclic compounds; containing an unfused triazine ring (whether or not hydrogenated) in the structure, others excluding melamine | 3.50% (2023 MFN average)WITS 2023 historical MFN average |