U.S. imports of Heterocyclic Compounds with Unfused Pyrazole Ring (SITC 51571) totaled $52.7M in August 2026, imported from 20 countries.
Importers of Heterocyclic Compounds with Unfused Pyrazole Ring paid $3.8M in duties in August 2026, an average duty rate of 12.38% — duty actually collected as a share of the imports that cleared customs, not the published tariff schedule.
Last updated: August 2026 dataPyrazole-ring heterocyclics — whether fully aromatic or hydrogenated — are a structurally defined subset of nitrogen-only heterocyclic compounds widely used as pharmaceutical active ingredients, agrochemical fungicides, and dye intermediates. The unfused ring requirement is the critical classification boundary: compounds where the pyrazole ring is fused to another ring system fall outside this grouping. Several pyrazole-based active pharmaceutical ingredients (APIs) sourced from Asia are subject to heightened supply-chain scrutiny given their role in finished drug manufacturing.
AI-written summary of the official U.S. Census Bureau trade figures on this page — verify before relying on it.
136 import shipments a month
An unfused pyrazole ring stands alone and is not joined to a second ring system. If the pyrazole ring is fused — for example, forming an indazole — the compound classifies under a different heterocyclic heading. This structural distinction is the primary classification decision point and should be confirmed with reference to the compound's structural formula.
Certain pyrazole intermediates and APIs sourced from China may be subject to Section 301 tariffs depending on the specific compound and its HTS classification. Importers should verify the applicable 10-digit HTS code and check current Section 301 lists before shipment.
Basic heading 72 of 465 in section 5
Basic heading 51571 · $52.7M of $27.5B
ImportsExports
Imports
$52.7MYoY · free account
Exports
$1.6MYoY · free account
12-mo low · imports
Low · free accountOver the twelve months to August 2026, the U.S. imported $534.8M of Heterocyclic Compounds with Unfused Pyrazole Ring and exported $42.1M.
Through August 2026. Source: U.S. Census Bureau.
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Imports · August 2026
origin
Switzerland and India together supply 78% of it.
customs district
Census does not publish district detail for this classification system.
destination
Census does not publish state detail for this classification system.
entry
Census does not publish port detail for this classification system.