Thiamine Propyl Disulfide from China
Thiamine propyl disulfide (TPD) offers improved bioavailability over thiamine HCl for oral supplements. Classified HTS 2936.22.00.00 as synthetic vitamin B1 derivative for nutritional fortification. Stable in tablet matrices.
Duty Rate — China → United States
100%
Rate breakdown
9903.04.60100%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.860%Universal product exemption (U.S. note 52(b))
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
• Disulfide bond stability testing required for 36-month shelf life claims
• Avoid bulk packaging >25kg to prevent HAZMAT shipping requirements