Theophylline Guaiacol Ester from Japan
Theophylline guaiacol ester modifies alkaloid pharmacokinetics for sustained release. Classifies HTS 2939.59.00.00 per ester rules following parent xanthine. Used in experimental pulmonology.
Duty Rate — Japan → United States
0%
Rate breakdown
9903.05.860%Universal product exemption (U.S. note 52(b))
Import Tips
• Ester linkage confirmation; guaiacol impurity limits; research-only labeling