DChloramphenicol (Dextro Form) from China
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 — China → United States
100%
Rate breakdown
9903.04.60100%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.860%Articles provided for in subdivision (b) of U.S. note 52 to this subchapter
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