HS 293352 Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure

Quick Answer: HS code 293352 encompasses a specific group of heterocyclic organic compounds characterized by the presence of a pyrimidine ring (which may be hydrogenated) or a piperazine ring in their molecular structure. These compounds are foundational in pharmaceuticals, agrochemicals, and specialty chemicals. For importers, duty rates vary significantly by destination. In the UK, the general Most Favoured Nation (MFN) duty rate is 6.00% ad valorem. The EU applies a general MFN rate of 6.50% ad valorem. The US tariff schedule shows a broader range, with some products classified under this heading entering duty-free, while others are subject to a 25% ad valorem duty, often indicative of Section 301 tariffs or specific product exclusions. Importers must verify the exact 10-digit subheading for precise duty assessment and to identify potential trade remedies or preferential agreements.

What Are the Import Duty Rates?

🇬🇧 United Kingdom

Code MFN Preferential Unit
2933520000 6.00 % — —
2933520090 6.00 % — —
2933520010 6.00 % — —

🇪🇺 European Union (TARIC)

Code MFN Preferential Unit
2933520010 6.50 % — —
2933520090 6.50 % — —
2933520000 6.50 % — —

🇺🇸 United States (HTSUS)

Code MFN Preferential Unit
2933521000 Free — ["kg"]
293352 — — —
2933529000 Free — ["kg"]

Duty rates sourced from the USITC (US International Trade Commission) Harmonized Tariff Schedule (HTS) (accessed 2/22/2026), EU TARIC – DG TAXUD (Directorate-General for Taxation and Customs Union) (accessed 2/22/2026), and UK Trade Tariff – HMRC (His Majesty's Revenue and Customs) (accessed 2/22/2026).

Data compiled and presented by HSRates.

How to Classify This HS Code?

What products does HS 293352 cover?

This subheading covers compounds containing a pyrimidine ring (whether or not hydrogenated) or a piperazine ring in their structure, specifically excluding those that are nucleic acids and their salts, or other heterocyclic compounds of heading 2933 that are more specifically provided for elsewhere. As defined by the World Customs Organization's Harmonized System Nomenclature and reflected in the USITC Harmonized Tariff Schedule of the United States (HTSUS) and the EU TARIC, this includes a broad range of organic chemical compounds where these specific nitrogen-containing heterocyclic rings are an integral part of their molecular architecture. Examples include certain pharmaceuticals, agrochemicals, and other fine chemicals where the pyrimidine or piperazine moiety is present.

What falls outside HS 293352?

The following products are excluded from HS 293352: nucleic acids and their salts, which are specifically classified under subheading 2934. Additionally, other heterocyclic compounds of heading 2933 that are more specifically enumerated in subsequent subheadings, such as those containing an un-condensed pyrazole ring (2933.11) or a phenothiazine ring system (2933.59), would be excluded. For instance, caffeine, while containing a pyrimidine ring, is specifically classified under 2939.30 as an alkaloid, demonstrating that more specific provisions take precedence. Similarly, certain vitamins, even if containing these rings, are classified under Chapter 29, heading 2936.

What are common classification mistakes for HS 293352?

A common error is misclassifying compounds that contain a pyrimidine or piperazine ring but are more specifically provided for elsewhere in Chapter 29 or even other chapters. Importers often overlook the principle of "more specific description" as outlined in General Interpretative Rule (GRI) 3(a), leading to incorrect classification. For example, a pharmaceutical product containing a pyrimidine ring might be incorrectly placed here when it should be classified under a more specific subheading for alkaloids (e.g., 2939) or provitamins and vitamins (e.g., 2936), if it meets the criteria for those headings. Another mistake is failing to recognize if the pyrimidine or piperazine ring is the *only* heterocyclic ring present, or if other, more specific heterocyclic rings are also present that would direct classification to a different subheading within 2933 or 2934.

How should importers classify products under HS 293352?

The correct procedure for classifying products under HS 293352 involves a systematic approach. Importers and customs brokers should first identify the complete chemical structure of the compound to confirm the presence of a pyrimidine or piperazine ring. Next, they must carefully review the entire Chapter 29, and specifically heading 2933, to ensure no other subheading provides a more specific description for the product, applying GRI 3(a). This includes checking for compounds that are nucleic acids and their salts (2934), alkaloids (2939), or vitamins (2936). Consulting official resources such as the WCO Explanatory Notes, the USITC HTSUS, and the EU TARIC is crucial to confirm the scope and exclusions, ensuring accurate and compliant classification and avoiding potential penalties or delays.

Which HS Codes Are Related?

HS 293332 HS 293331 HS 293321 HS 293311 HS 293361 HS 293341

Not the right code? Search all HS codes to find the correct tariff classification.

FAQ

What is the Most Favored Nation (MFN) import duty rate for products classified under HS 2933.52 in major markets?

The MFN (Most Favored Nation) import duty rate for HS 2933.52, covering 'Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure,' varies by importing country. For example, the United States generally applies a 6.5% ad valorem duty rate under the Harmonized Tariff Schedule of the United States (HTSUS). The European Union's TARIC database typically shows a 6.5% ad valorem rate. The UK Global Tariff also commonly applies a 6.5% ad valorem rate. It is crucial for importers to verify the specific duty rate applicable to their destination country using the official tariff schedules (e.g., USITC HTSUS, EU TARIC, UK Trade Tariff) as rates can be subject to change or specific conditions.

How do I determine if my chemical compound correctly classifies under HS 2933.52?

Classification under HS 2933.52 hinges on the presence of a pyrimidine ring (whether or not hydrogenated) or a piperazine ring within the chemical structure of the compound. This heading specifically covers heterocyclic compounds with nitrogen hetero-atom(s) only. Importers must ensure that the primary chemical structure contains one of these specified rings. If the compound contains other types of heterocyclic rings or additional hetero-atoms (e.g., oxygen, sulfur) that define its character, or if it is a provitamin or vitamin, it might fall under a different heading. A detailed chemical analysis, often including a Certificate of Analysis (CoA) or Material Safety Data Sheet (MSDS) detailing the chemical structure, is essential for accurate classification, aligning with the General Rules of Interpretation (GRIs) and Explanatory Notes to the Harmonized System (WCO).

Are there any preferential duty rates available for HS 2933.52 under common trade agreements?

Yes, preferential duty rates, including 'Free' rates, are often available for HS 2933.52 under various free trade agreements (FTAs) or generalized system of preferences (GSP) schemes, provided the goods meet the respective rules of origin. For instance, goods originating from countries party to agreements like the USMCA (United States-Mexico-Canada Agreement), EU-Japan EPA, or various GSP programs may qualify for reduced or zero duties upon importation into the US, EU, or UK. Importers should consult the specific trade agreement's rules of origin and ensure they possess the necessary documentation, such as a Certificate of Origin, to claim preferential treatment. Failure to meet origin requirements will result in the application of the MFN duty rate.

What documentation is typically required for customs clearance of products classified under HS 2933.52?

For customs clearance of chemical compounds under HS 2933.52, standard import documentation includes a commercial invoice, packing list, and bill of lading or air waybill. Additionally, due to the chemical nature of these products, a Certificate of Analysis (CoA) or Material Safety Data Sheet (MSDS) is frequently requested by customs authorities to verify the chemical composition and ensure compliance with safety and regulatory standards. If claiming preferential duty rates under a free trade agreement, a valid Certificate of Origin (e.g., USMCA Certificate of Origin, EUR.1 movement certificate) is mandatory. Depending on the specific compound and its end-use, additional permits or licenses from regulatory bodies (e.g., FDA in the US, EMA in the EU for pharmaceutical intermediates) may be required.

Could HS 2933.52 products be subject to additional duties, such as Section 301 tariffs in the United States?

Yes, products classified under HS 2933.52 could potentially be subject to additional duties, such as Section 301 tariffs in the United States, if they originate from countries targeted by such measures (e.g., China). While the standard MFN duty rate for HS 2933.52 is 6.5% ad valorem in the US, certain compounds from China have historically been subject to additional Section 301 duties, which could be as high as 25% ad valorem on top of the MFN rate. Importers must regularly check the latest USTR (United States Trade Representative) announcements and HTSUS Chapter 99 notes to determine if their specific product and country of origin are affected by these additional duties. Similar trade remedy duties (e.g., anti-dumping or countervailing duties) could also apply in other jurisdictions, requiring careful verification.