Tryptophan from Japan
L-Tryptophan is an essential amino acid featuring an indole side chain attached to alanine, classified under HTS 2933.99.0500 due to its indole structure. The heterocyclic nitrogen compound takes precedence over amino acid classification.
Duty Rate — Japan → United States
15%
Rate breakdown
9903.04.6215%Pharmaceuticals: patented pharma from JP/EU/KR/CH/LI — 15% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Indole amino acids classified here, not with other amino acids, per heterocyclic precedence
• Pharma grade requires USP certificate; feed grade may have different documentation
• Avoid Chapter 29 note 3(C) salt classification issues with pure free acid form