Tralopyril 

Tralopyril is an orally active, blood-brain barrier-penetrating antifouling insecticide and endocrine disruptor. By interfering with the thyroid hormone system and mitochondrial oxidative phosphorylation, Tralopyril downregulates the transcription of genes such as TRHR, Nkx2.1, TRα and induces ferroptosis. Tralopyril disrupts amino acid, energy and lipid metabolism, exhibits significant skeletal and reproductive toxicity, and causes developmental damage. Tralopyril has a long half-life in vivo and wide tissue distribution, posing potential risks to aquatic organisms and human health. Tralopyril shows species specificity in in vitro liver microsomal metabolism, exerts lethal effects on target insects and laboratory animals, and is commonly used in studies of chlorfenapyr poisoning and related toxic mechanisms^[1][2][3][4].

Tralopyril potently inhibits growth, ATP production, and effective quantum yield in Chlamydomonas reinhardtii cells^[1].
Tralopyril (200 μM; 0, 5, 15, 30, 45, 60 min) exhibits low metabolic clearance in human and monkey liver microsomes, moderate clearance in mouse, rat, and dog liver microsomes, with interspecies differences in in vitro metabolic stability^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Tralopyril (1-10 μg/L; waterborne; continuous; 195 days) induces persistent, transgenerational reproductive and skeletal toxicity in Oryzias melastigma via endocrine disruption of the HPG and HPT axes, with ferroptosis as a key mechanistic link, evidenced by dose-dependent increases in IBR values, altered hormone levels, dysregulated gene expression, and multigenerational tissue and phenotypic defects^[2].
Tralopyril (45 mg/kg; p.o.), the in vivo metabolite of chlorfenapyr, has a significantly longer half-life (5.39 h), higher AUC_0-t, and higher C_max than chlorfenapyr, and it distributes widely across all mouse tissues including the brain^[3].
Tralopyril (27 mg/kg; p.o.; single dose) has an oral LD₅₀ of 27 mg/kg in male rats, indicating acute lethal toxicity via this route^[4].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

349.53

C₁₂H₅BrClF₃N₂

122454-29-9

Solid

White to off-white

C1=C(C=CC(=C1)Cl)C2=C(C#N)C(=C(C(F)(F)F)N2)Br

Room temperature in continental US; may vary elsewhere.

* Please refer to the solubility information to select the appropriate solvent. Once prepared, please aliquot and store the solution to prevent product inactivation from repeated freeze-thaw cycles.
Storage method and period of stock solution: -80°C, 6 months; -20°C, 1 month. When stored at -80°C, please use it within 6 months. When stored at -20°C, please use it within 1 month.

• [1]. Chen X, et al. Tralopyril induces developmental toxicity in zebrafish embryo (Danio rerio) by disrupting the thyroid system and metabolism. Sci Total Environ. 2020;746:141860.  [Content Brief]

  [2]. Liu B, et al. Transgenerational toxicity of Tralopyril: Ferroptosis mediates reproductive and skeletal disruption in Oryzias melastigma[J]. Environmental Chemistry and Ecotoxicology, 2026.

  [3]. Zhang S, et al. Toxicokinetics, in vivo metabolic profiling and tissue distribution of chlorfenapyr in mice. Arch Toxicol. 2024;98(11):3763-3775.  [Content Brief]

  [4]. Chung MJ, et al. A Fatal Case of Chlorfenapyr Poisoning and the Therapeutic Implications of Serum Chlorfenapyr and Tralopyril Levels. Medicina (Kaunas). 2022;58(11):1630. Published 2022 Nov 11.  [Content Brief]