N,N'-Bis(trimethylsilyl) Urea Technical Grade from China
Technical grade N,N'-Bis(trimethylsilyl) urea (95%+ purity) serves as silylating reagent for carbohydrate protection in nucleoside synthesis. Specifically enumerated in HTS 2931.90.70.00 distinguishing it from general silanes.
Duty Rate — China → United States
35%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
Import Tips
• Technical vs. 99% grades identical classification but purity affects DEA precursor watch lists
• Air-sensitive; requires inert atmosphere packaging certification for import inspection
• Pharma importers need DMF/CEP documentation linking to FDA drug master files