1-Methylxanthine from Canada
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.
Duty Rate — Canada → United States
110%
Rate breakdown
9903.04.6093.5%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.2910%Except for products described in headings 9903.05.85–9903.05.93, articles the product of Canada, as provided for in U.S. note 52 to this subchapter
Import Tips
• 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