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Aminophylline Base from Canada

Aminophylline base, theophylline ethylenediamine complex, qualifies as heterocyclic nitrogen compound before salt formation considerations. U.S. note 3 product in 2933.99.79.00. Used in respiratory therapy intermediates.

Duty Rate — Canada → United States

16.5%

Rate breakdown

9903.05.2910%Section 301 (forced labor) — additional 10% ad valorem on products of Canada

Import Tips

Specify base vs salt form clearly with assay method documentation

Test for ethylenediamine content to confirm stoichiometric ratio

Declare moisture content affecting stability during customs valuation