# United States tariff line 2933.53.00.00: Allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof

> In the United States tariff, line 2933.53.00.00 covers compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof. Goods under this line enter free of general (MFN) duty. It falls under HS subheading 2933.53 in heading 29.33 (chapter 29).

Source: https://border.bot/countries/united-states/hs-codes/2933530000
Last updated: 9 October 2026

[Countries](https://border.bot/countries) / [United States](https://border.bot/countries/united-states) / [Chapter 29](https://border.bot/countries/united-states/hs-codes/29) / [2933.53](https://border.bot/countries/united-states/hs-codes/293353) / [2933.53.00.00](https://border.bot/countries/united-states/hs-codes/2933530000)

## Key facts

- Tariff line: 2933.53.00.00
- Covers: Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof
- Duty (MFN): Free
- Additional duties: None recorded
- Restrictions: None recorded
- Tariff: [United States](https://border.bot/countries/united-states)
- HS subheading: [2933.53](https://border.bot/hs-codes/293353)

## What this line covers

In the United States tariff, line 2933.53.00.00 covers compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof.

Its legal text is “Allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof”, read under “Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure”.

## How it is structured

It falls under HS subheading 2933.53 in heading 29.33 (chapter 29). The first six digits are the Harmonized System code; the 4 digits after them are added by the United States tariff.

- Chapter 29: Organic chemicals
- Heading 29.33: Heterocyclic compounds with nitrogen hetero-atom(s) only
- Subheading 2933.53: Compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure
- Line 2933.53.00.00: Allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof

## Duty

Goods under this line enter free of general (MFN) duty.

## In other countries

No other national tariff on border.bot has live lines under 2933.53 yet.

- [The Harmonized System text for 2933.53](https://border.bot/hs-codes/293353)

- Previous line: [2933.52.90.00](https://border.bot/countries/united-states/hs-codes/2933529000) Other
- Next line: [2933.54.00.00](https://border.bot/countries/united-states/hs-codes/2933540000) Other derivatives of malonylurea (barbituric acid); salts thereof

## Frequently asked questions

### What does tariff line 2933.53.00.00 cover in the United States tariff?

In the United States tariff, line 2933.53.00.00 covers compounds containing a pyrimidine ring (whether or not hydrogenated) or piperazine ring in the structure, allobarbital (INN), amobarbital (INN), barbital (INN), butalbital (INN), butobarbital, cyclobarbital (INN), methylphenobarbital (INN), pentobarbital (INN), phenobarbital (INN), secbutabarbital (INN), secobarbital (INN) and vinylbital (INN); salts thereof.

### What is the general (MFN) duty on 2933.53.00.00 in the United States?

Goods under this line enter free of general (MFN) duty.

## Sources and updates

The tariff lines for the United States come from border.bot release 1 (edition 2026HTSRev21), read from the publisher’s files, and have been live since 9 October 2026.

The duty rates for the United States come from border.bot release 1 (edition 2026HTSRev21), read from the publisher’s files, and have been live since 9 October 2026.

The trade programmes for the United States come from border.bot release 1 (edition 2026HTSRev21), read from the publisher’s files, and have been live since 9 October 2026.

This page was last updated on 9 October 2026.

Guidance from published tariff data, not a binding ruling. For a decision customs must follow, apply to the destination’s customs authority for a binding tariff ruling.

Official source files:

- https://hts.usitc.gov/reststop/exportList?from=0000000000&to=9999999999&format=CSV&styles=false

Machine-readable: https://border.bot/countries/united-states/hs-codes/2933530000.json