4-Fluorophenylalanine from Mexico
4-Fluorophenylalanine is a halogenated aromatic amino acid used in PET imaging tracers and protein engineering, falling under HTS 2922.49.37.00. The fluorine substitution doesn't alter its oxygen-function amino-acid classification per chapter note 4. Qualifies as chemically defined compound of note (a).
Duty Rate — Mexico → 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 fluorine-19 NMR data confirming substitution pattern; halogenated derivatives stay in parent heading
• Declare under TSCA with fluorochemical notification if >10,000 lbs/year
• Avoid classifying as 'radioactive materials' (2844) unless C-11 or F-18 labeled isotopes