2933.53.00.00
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
Classification path
- Heterocyclic compounds with nitrogen hetero-atom(s) only
- Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure
- 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
Rates of duty
- General (MFN)
- Free
- Column 2Cuba, North Korea, Russia, Belarus
- 50%
- Unit of quantity
- kg
Related lines in heading 2933
- 2933.11.00.00Phenazone (Antipyrine) and its derivatives6.5%
- 2933.19.04.00Aminomethylphenylpyrazole (Phenylmethylaminopyrazole); and 3-Methyl-1-(p-tolyl)-2-pyrazolin-5-one (p-Tolyl methyl pyrazolone)Free
- 2933.19.08.003-(5-Amino-3-methyl-1H-pyrazol-1-yl)- benzenesulfonic acid; Amino-J-pyrazolone; 3-Amino-1-(2,4,6-trichlorophenyl)-5- pyrazolone; 3-Carboxy-1,4-sulfophenylpyrazol-5-one; 4-Chloro-3-(3-methyl-5-oxo-2-pyrazolin-1- yl)benzenesulfonic acid; 1-(m-Chlorophenyl)-3-methyl-2-pyrazolin- 5-one;p-Chloropyrazolone; 1-(2',5'-Dichlorophenyl)-3-methyl-2- pyrazolin-5-one; 1-(o-Ethylphenyl)-3-methyl-2-pyrazolin- 5-one; 5-Imino-3-methyl-1-phenylpyrazole; 5-Imino-3-methyl-1-(m-sulfophenyl)- pyrazole; 2,4-Methylcarboxypyrazolic acid; Methylphenylpyrazolone; and Sulfinpyrazone5.8%
- 2933.19.15.001,2-Dimethyl-3,5-diphenyl-1H-pyrazolium methyl sulfate (Difenzoquat methyl sulfate)Free
- 2933.19.18.002-Chloro-5-sulfophenylmethylpyrazolone; 2,5-Dichloro-4-(3-methyl-5-oxo-2- pyrazolin-1-yl) benzenesulfonic acid; Phenyl carbethoxypyrazolone;m-Sulfaminopyrazolone (m-Sulfamido- phenyl methyl pyrazolone); and 1-(p-Sulfophenyl)-3-methyl pyrazoloneFree
- 2933.19.23.00Heterocyclic compounds with nitrogen hetero-atom(s) only / Aromatic or modified aromatic / Pesticides6.5%
- 2933.19.30.10Couplers, for use in color negative photographic paper6.5%
- 2933.19.30.95Aromatic or modified aromatic / Photographic chemicals / Other6.5%
- 2933.19.35.00Heterocyclic compounds with nitrogen hetero-atom(s) only / Aromatic or modified aromatic / Drugs6.5%
- 2933.19.37.00Products described in additional U.S. note 3 to section VI6.5%
- 2933.19.43.00Heterocyclic compounds with nitrogen hetero-atom(s) only / Aromatic or modified aromatic / Other6.5%
- 2933.19.45.00Heterocyclic compounds with nitrogen hetero-atom(s) only / Drugs3.7%
About heading 2933
Heterocyclic compounds with nitrogen hetero-atom(s) only
Heading 2933 covers heterocyclic compounds that contain only nitrogen as the hetero-atom, meaning the ring system has nitrogen but no oxygen, sulfur or other hetero-atom in the ring. The heading is split by ring type: unfused pyrazole, imidazole, pyridine, quinoline and isoquinoline, pyrimidine and piperazine, triazine, then lactams, then a residual Other group. Within each ring group the lines separate aromatic from non-aromatic forms and then break out pesticides, drugs, photographic chemicals and specific named compounds.
Full guide to heading 2933Products in this heading
- Melamine (2933.61.00.00)
- Diazepam (2933.91.00.50)
- 6-Hexanelactam, also called caprolactam (2933.71.00.00)
- N-Methyl-2-pyrrolidone (2933.79.20.00)
- Hexamethylenetetramine (2933.69.50.00)
- Cyanuric chloride (2933.69.60.10)
- Benzotriazole (2933.99.82.10)
- Piperidine (2933.32.10.00)
Frequently asked questions
What is the HTS code for melamine?
Melamine is classified under 2933.61.00.00, the line for melamine in the unfused triazine group. The general (MFN) rate for that line is 3.5%.
What is the duty on diazepam imported into the United States?
Diazepam falls under 2933.91.00.50, the residual line for the named benzodiazepines and their salts. The general (MFN) rate on that line is Free.
How do I classify caprolactam?
Caprolactam, described as 6-hexanelactam, is a lactam and is named in 2933.71.00.00. The general (MFN) rate for that line is 6.5%.
Source: USITC Harmonized Tariff Schedule, retrieved October 21, 2026.