Paraxanthine Reference Standard from Japan
Paraxanthine is a caffeine metabolite with a xanthine (pyrimidine-containing) structure, supplied as analytical reference material. Falls under HTS 2933.59.70.00 for aromatic pyrimidines listed in additional U.S. note 3. Used in lab research and pharma development.
Duty Rate — Japan → United States
6.5%
Rate breakdown
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Import Tips
• Include stability data and intended research use declaration to avoid pharma drug scrutiny
• Use small package sizes (<1kg) typical for standards to prevent bulk chemical treatment
• Cross-check with FDA for any import alerts on xanthine metabolites