Pteridine from Mexico
Pteridine is a fused heterocyclic system containing pyrimidine and pyrazine rings, essential for biochemical research and vitamin synthesis. Classified under HTS 2934.99.44.00 as an aromatic heterocyclic compound not elsewhere specified. Used in folate and flavin coenzyme production.
Duty Rate — Mexico → 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
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include NMR or HPLC analysis confirming aromatic heterocyclic structure for customs classification
• Declare intended research use to avoid pharmaceutical classification under Chapter 30
• Package with stabilizers if required for air transport per chapter note 2(f)