Products described in additional U.S. note 3 to section VI
Heterocyclic compounds with nitrogen hetero-atom(s) only: > Compounds containing an unfused pyridine ring (whether or not hydrogenated) in the structure: > Other: > Other: > Other: > Products described in additional U.S. note 3 to section VI
Duty Rate (from China)
Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Subheadings
Products classified under HTS 2933.39.61
Nicotine Bitartrate Dihydrate
Nicotine bitartrate dihydrate is a heterocyclic compound containing an unfused pyridine ring, used primarily in pharmaceutical formulations for smoking cessation aids like nicotine gums and patches. It falls under HTS 2933.39.61 as a pyridine derivative specified in additional U.S. note 3 to section VI, which covers certain regulated organic chemicals. This salt form ensures stability for medical applications.
Pyridine-3-Carboxylic Acid (Niacin)
Pyridine-3-carboxylic acid, commonly known as niacin or vitamin B3, is a chemically defined compound with an unfused pyridine ring used in nutritional supplements and pharmaceuticals. Classified under HTS 2933.39.61 per additional U.S. note 3 to section VI for specific pyridine derivatives. It's imported as a bulk API for fortification of foods and multivitamins.
Ethyl Nicotinate
Ethyl nicotinate is the ethyl ester of nicotinic acid, featuring an unfused pyridine ring, used topically in pharmaceuticals for peripheral vasodilator effects and in cosmetics. It qualifies for HTS 2933.39.61 under additional U.S. note 3 to section VI as a specified pyridine derivative. Commonly imported for compounding in creams and gels.
Methyl Nicotinate
Methyl nicotinate, a pyridine-3-carboxylate methyl ester, is used in topical rubefacients and veterinary pharmaceuticals for its counterirritant properties. This unfused pyridine ring compound is covered by HTS 2933.39.61 via additional U.S. note 3 to section VI. Bulk imported for transdermal applications.
Isonicotinic Acid Hydrazide (INH)
Isonicotinic acid hydrazide (INH), or isoniazid, contains an unfused pyridine ring and serves as a first-line antituberculosis drug API. Classified in HTS 2933.39.61 per additional U.S. note 3 to section VI for specified pyridine compounds. Essential for generic TB treatment manufacturing.
Pyridine-4-Carboxylic Acid
Pyridine-4-carboxylic acid (isonicotinic acid) is a key intermediate with an unfused pyridine ring used in synthesizing pharmaceuticals like isoniazid. It falls under HTS 2933.39.61 as specified in additional U.S. note 3 to section VI. Primarily imported for fine chemical synthesis.
2-Aminopyridine
2-Aminopyridine is a simple unfused pyridine ring compound with an amino group, used as a chemical intermediate in agrochemicals and pharmaceuticals. Covered by HTS 2933.39.61 through additional U.S. note 3 to section VI for regulated pyridines. High-purity grades for synthesis.
4-Dimethylaminopyridine (DMAP)
4-Dimethylaminopyridine (DMAP) is a pyridine catalyst with an unfused ring, widely used in organic synthesis for acyl transfer reactions. HTS 2933.39.61 applies via additional U.S. note 3 to section VI for listed pyridine derivatives. Essential lab reagent for peptide manufacturing.
Nicotyrine
Nicotyrine is a pyridine derivative found in tobacco, containing an unfused pyridine ring fused with pyrrole, used in tobacco research and flavor chemistry. Classifies under HTS 2933.39.61 per additional U.S. note 3 to section VI. Reference standard for analytical labs.
Pyrithione Zinc (Zinc Pyrithione)
Zinc pyrithione is an organo-zinc coordination compound with pyridine-thione structure, used as antifungal in shampoos. The organic pyridine component qualifies it for HTS 2933.39.61 under additional U.S. note 3 to section VI. Bulk active for personal care products.
Vinylpyridine Polymer Monomer
4-Vinylpyridine monomer contains an unfused pyridine ring and serves as raw material for ion-exchange resins and adhesives. HTS 2933.39.61 covers it via additional U.S. note 3 to section VI for regulated pyridines. Inhibitor-stabilized for polymerization control.