4-Methylumbelliferone (CAS 90-33-5) from China
4-Methylumbelliferone (4-MU) is a methylcoumarin derivative classified in HTS 2932.20.0500 for its coumarin lactone structure. Widely used as a fluorogenic substrate in biochemical assays and as a laser dye.
Duty Rate — China → United States
19%
Rate breakdown
9903.05.3112.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of China, as provided for in U.S. note 52 to this subchapter
Import Tips
• Provide fluorescence emission spectra data to confirm identity for lab/research imports
• Declare if crystalline powder or solution form; pure compound stays in 2932
• Include end-use statements for research chemicals to avoid pharmaceutical scrutiny