DChloramphenicol (Dextro Form) from Canada
D-threo isomer of chloramphenicol, the biologically active enantiomer used in synthesis of pure antibiotic derivatives. Classified HTS 2941.40.00.00 as chemically defined chloramphenicol derivative per chapter note 1(a). Intermediate for high-purity drug manufacturing.
Duty Rate — Canada → 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
• Chiral purity certificate (>99% ee) mandatory; racemic mixtures reclassify under general antibiotics
• Controlled temperature (-20°C) shipping prevents racemization; declare optical rotation [+18° to +20°]
• Research chemical declarations require end-user statements to avoid Schedule H drug controls