Sourcing thiazoles and other heterocyclics from China
Heterocyclic compounds of heading 2934 from China, such as thiazoles, benzothiazoles, phenothiazines and nucleic acids, pay 0% UK duty as listed pharmaceutical substances and 6% otherwise, with no anti-dumping duty. UK REACH applies from one tonne a year, active substances for medicines need MHRA registration, and fentanyls are controlled drugs. Cambridge China Bridge sources them.
Thiazoles, benzothiazoles, phenothiazines and nucleic acids pay 0% or 6% UK duty from China. Pharmaceutical relief, REACH and drug controls explained.
Two rates on most lines
Read from the UK Trade Tariff on 25 September 2026, most heading 2934 lines carried two third-country rates: 0% for pharmaceutical substances in the tables of the Reliefs Regulations, under additional code 2500, and 6% for everything else, under 2501. Mercaptobenzothiazole and its disulphide carried a flat 6%, and some named drug substances a flat 0%. None had an anti-dumping measure.
Give the broker the name and CAS number of each substance; the pharmaceutical intermediates guide explains the additional codes for the neighbouring heading.
| Goods | Commodity code | Duty | Anti-dumping duty on China |
|---|---|---|---|
| Compounds with an unfused thiazole ring, other | 2934 10 00 90 | 0% pharmaceutical / 6% other | None |
| Mercaptobenzothiazole and its disulphide | 2934 20 20 00 | 6% | None |
| Other benzothiazoles | 2934 20 80 90 | 0% pharmaceutical / 6% other | None |
| Phenothiazines, other | 2934 30 90 90 | 0% pharmaceutical / 6% other | None |
| Other fentanyls and their derivatives | 2934 92 00 00 | 0% pharmaceutical / 6% other | None |
| Other heterocyclics and nucleic acids | 2934 99 90 90 | 0% pharmaceutical / 6% other | None |
Controlled drugs
Section 3 of the Misuse of Drugs Act 1971 prohibits importing a controlled drug except under a Home Office licence or as the regulations allow. Several heading 2934 substances, including fentanyls and the listed benzodiazepine-type compounds, are controlled drugs, so no order should be placed until the licence is in hand.
REACH and medicines rules
Importing a substance at one tonne or more a year needs UK REACH registration or an only-representative arrangement. Active substances for licensed human medicines can only be imported by a person registered with the MHRA under the Human Medicines Regulations 2012, and the factory's GMP evidence will be checked.
Agrochemical actives such as fosthiazate and hexythiazox, listed in the tariff, also need pesticide approval before use in Great Britain.
Documents and samples
Ask for a certificate of analysis for every batch, the safety data sheet in English, and the route of synthesis where impurities matter. Test the first batch in a UK laboratory, and ship under dangerous goods rules where the SDS requires.
Cambridge China Bridge sources heterocyclic chemicals and intermediates, with licences, registration and batch documents settled before the order. See how our sourcing service works.
Frequently asked questions
What is the UK import duty on heterocyclic compounds from China?
Read from the UK Trade Tariff on 25 September 2026, most heading 2934 lines carried 0% for listed pharmaceutical substances and 6% otherwise, with no anti-dumping duty.
Can I import fentanyl intermediates?
Only under a Home Office licence. Section 3 of the Misuse of Drugs Act 1971 prohibits importing a controlled drug without one.
Do I need MHRA registration to import an API?
Yes, for active substances used in licensed human medicines, under the Human Medicines Regulations 2012.
What duty applies to MBT rubber accelerator?
Mercaptobenzothiazole and its disulphide carried a flat 6% from China on 25 September 2026.