2-Mercaptobenzoic Acid from Canada
2-Mercaptobenzoic acid contains a thiol group ortho to carboxylic acid on benzene ring, classified under HTS 2930.90.4950 as other organo-sulfur acid. Direct C-S bonding qualifies for heading 2930; aromatic structure doesn't change classification. Used in synthesis of thiochromones and dyes.
Duty Rate — Canada → United States
110%
Rate breakdown
9903.04.6095.8%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 HPLC purity (>98%) and tautomer confirmation (thiol vs thione form)
• Verify no sulfonation occurred during synthesis per exclusion note 6
• Package under nitrogen to prevent air oxidation during transport