Penicillamine from China
D-Penicillamine, 3-mercapto-D-valine, is a mercaptocarboxylic amino acid used in Wilson's disease treatment. The free mercapto and carboxylic functions qualify it for HTS 2930.90.4920 classification as organo-sulfur compound. Chapter 29 takes precedence over amino acid headings.
Duty Rate — China → United States
125%
Rate breakdown
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.04.6095.8%Pharmaceuticals Annex IV: patented pharma articles — 100% 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
• Chiral HPLC certificate required showing D-isomer >99%; CAS 52-67-5
• Oxidation-sensitive; import with antioxidant stabilizer per Chapter 29 note 2(f)
• Distinguish from 2922.50 amino acid salts by free base form