1-Methylxanthine
1-Methylxanthine is a purine alkaloid metabolite and research chemical with nitrogen-only heterocyclic structure under 2933. Covered by additional U.S. note 3 specifications. Used in biochemical research and pharmaceutical synthesis.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If non-aromatic saturated structure
Saturated heterocyclic compounds classify earlier in 2933.59, not aromatic subheading.
If classified primarily by carboxamide function
If nitrogen function dominates over heterocyclic, moves to chapter 29 heading 2924.
If diagnostic reagent grade with added stabilizers
Lab reagents with formulation additives exclude from pure compounds in chapter 29.
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Import Tips & Compliance
• Include NMR or mass spec data confirming structure matches reference standard
• Label as 'research chemical - not for human consumption' to avoid FDA drug scrutiny
• Verify no heavy metal contaminants per USP <232> limits for pharma intermediates
Related Products under HTS 2933.99.79.00
Caffeine Anhydrous Powder
Pure caffeine anhydrous is a xanthine alkaloid classified as a heterocyclic compound with nitrogen hetero-atoms only, specifically under aromatic or modified aromatic structures in heading 2933. It falls into 2933.99.79.00 due to U.S. note 3 specifications for certain pharmaceutical intermediates. Used in energy drinks, supplements, and medications.
Theophylline USP Grade
Theophylline is a methylxanthine drug and bronchodilator, a purine derivative with fused heterocyclic nitrogen rings fitting 2933 classification. Specified in U.S. note 3 to section VI for this subheading. Used in respiratory medications and as chemical intermediate.
Paraxanthine
Paraxanthine, a caffeine metabolite, features dimethylxanthine structure with nitrogen hetero-atoms in fused rings, aromatic per 2933.99. Falls under U.S. note 3 products. Applied in sports nutrition and metabolic research.
Theobromine Powder
Theobromine, a xanthine alkaloid from cocoa, has purine heterocyclic nitrogen structure qualifying for 2933.99.79.00 per U.S. note 3. Used in cosmetics, pharma intermediates, and veterinary medicine.
8-Bromotheophylline
8-Bromotheophylline serves as a pharmaceutical intermediate with halogenated xanthine structure, nitrogen heterocyclic only per chapter notes. Included in U.S. note 3 products for 2933.99.79.00. Used in synthesis of bronchodilators.
Pentoxifylline API
Pentoxifylline is a xanthine derivative used as active pharmaceutical ingredient for circulation disorders, with methylxanthine core fitting 2933 nitrogen heterocycles. U.S. note 3 designated product. Bulk API form excludes finished drugs.