4-Carbazoleboronic Acid from Mexico
4-Carbazoleboronic acid retains the core carbazole heterocyclic structure with boronic acid substitution, classified as modified aromatic under HTS 2933.99.11.00 per Chapter 29 organo-inorganic compound rules. Essential Suzuki coupling reagent for pharmaceutical synthesis.
Duty Rate — Mexico → United States
110%
Rate breakdown
9903.04.60100%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
• Air-sensitive compound requires inert atmosphere packaging; document stability data to prevent decomposition claims
• Often imported under refrigerated conditions (-20°C); include temperature monitoring records for customs
• Boronic acid function doesn't override heterocyclic classification per Chapter 29 note on coordination compounds