2,3,5-Triiodobenzoic acid (TIBA) targets polar auxin transport in plants, acting as a non-competitive inhibitor of auxin efflux carriers. Auxin is a key plant hormone that regulates growth and development, including cell elongation, apical dominance, and root formation. By inhibiting auxin transport, TIBA disrupts normal auxin distribution, leading to altered plant growth patterns. The compound's mechanism involves binding to auxin efflux carriers, preventing the directional movement of auxin through plant tissues. As a plant growth regulator and herbicide, TIBA is used in agricultural applications.

inhibitor of auxin transport.

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In vitro studies have demonstrated that 2,3,5-Triiodobenzoic acid is a non-competitive polar auxin transport inhibitor. The compound inhibits auxin efflux from cells, disrupting normal auxin distribution patterns. In plant-based assays, TIBA treatment results in altered growth responses including inhibition of elongation, promotion of lateral branching, and other auxin-related phenotypes. The compound's activity is concentration-dependent and specific to auxin transport mechanisms. TIBA has been used extensively as a tool to study auxin transport and plant development.

In vivo studies have demonstrated that 2,3,5-Triiodobenzoic acid is effective as a plant growth regulator, defoliant, and agricultural herbicide. When applied to plants, TIBA alters growth patterns by disrupting auxin transport. The compound has been studied in various plant species for its effects on growth, development, and yield. Its use as a herbicide and defoliant is based on its ability to disrupt normal plant hormone signaling, leading to growth inhibition or plant death. The compound's efficacy in agricultural applications has been well established.

Cell-free biochemical assays for 2,3,5-Triiodobenzoic acid typically measure inhibition of auxin transport or binding to auxin transport proteins. A standard protocol involves isolating membrane vesicles from plant tissues and measuring auxin uptake or efflux using radiolabeled auxin (e.g., [³H]-IAA) in the presence of varying concentrations of TIBA (0.1-100 μM). The compound's binding to auxin efflux carriers can be assessed by competitive binding assays. IC₅₀ values are determined from dose-response curves using nonlinear regression analysis. Assays are performed in triplicate with appropriate controls.

Cell-based assays for 2,3,5-Triiodobenzoic acid typically use plant cell cultures or tissues to assess auxin transport inhibition. A standard protocol involves culturing plant cells or excised plant tissues in appropriate media, treating with TIBA at concentrations ranging from 1-100 μM for 1-24 hours, and measuring auxin transport using radiolabeled auxin or by monitoring growth responses. Auxin-responsive gene expression can be measured by qPCR. The compound's effects on cell elongation, division, and differentiation can be assessed microscopically.

In vivo studies for 2,3,5-Triiodobenzoic acid are typically conducted in plants to assess its effects on growth and development. A standard protocol involves applying TIBA to plants (e.g., Arabidopsis thaliana, crop species) at concentrations ranging from 10-1000 μM, either by foliar spray, root application, or incorporation into growth media. Plant growth parameters such as height, root length, branching patterns, and biomass are measured over several days to weeks. Auxin transport is assessed using radiolabeled auxin or by monitoring gravitropic and phototropic responses. The compound's herbicidal efficacy is evaluated by measuring plant survival and growth inhibition.

Absorption, Distribution and Excretion
This study investigated placental transport of 2,3,5-triiodobenzoic acid (2,3,5-triiodobenzoic acid) and its metabolites using 14C-labeled 2,3,5-triiodobenzoic acid. Placental transport of 2,3,5-triiodobenzoic acid and its metabolites was observed in both cold-stress and control rats. The concentrations of 2,3,5-triiodobenzoic acid and its metabolites in the maternal blood of both cold-stress and control rats were significantly higher than those in the corresponding fetal blood. However, cold stress did not significantly alter placental transport or the levels of 2,3,5-triiodobenzoic acid and its metabolites in maternal and fetal tissues. Cold stress had no significant effect on the concentrations of 2,3,5-triiodobenzoic acid, 2,5-diiodobenzoic acid, or 3,5-diiodobenzoic acid in maternal or fetal plasma. Non-pregnant rats were able to adapt to cold stress, while pregnant rats were not, suggesting a possible synergistic effect between cold stress and pregnancy. Rats orally administered C14-carboxyl or 2,3(125-I),5(125-I)-triiodobenzoic acid showed 72-75% radioactivity excreted in urine and 24-28% in feces within 4 days post-administration. Peak concentrations of carbon-14 were observed in the brain, thyroid gland, liver, lungs, heart, spleen, kidneys, and carcass at 4 or 8 hours post-administration, followed by a rapid decline. Iodine-125 levels in the brain and thyroid gland were significantly higher than carbon-14 levels. Iodine-125 levels in the thyroid gland increased over time. ...

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Metabolism/Metabolites
Rats orally administered C14-carboxyl or 2,3(125-I),5(126-I)-triiodobenzoic acid showed 72-75% radioactivity excreted in urine and 24-28% in feces within 4 days post-administration... Thin-layer chromatography (TLC) of urine ether extracts (extracting 50-80% of the radioactivity) showed the presence of: 2,5-diiodobenzoic acid, in the form of free acid and conjugates, accounting for 66% of the extractable radioactivity (39.6% of the dose); unchanged triiodobenzoic acid, 9.5% (5.7% of the dose); 2-hydroxy-3,5-diiodobenzoic acid, 2.3% (1.4% of the dose); and 3,5-diiodobenzoic acid, 0.7% (0.4% of the dose). TLC of fecal extracts showed a metabolic pattern similar to that of urine. This study investigated the systemic retention, excretion, distribution, thyroid uptake, and metabolism of 2(131I),3,5-triiodobenzoic acid (TIBA) in goats and a cow. Following a single oral dose of TIBA, the systemic radioactivity retention curve exhibited a two-component characteristic, with primary excretion via urine. TIBA and nine of its metabolites were detected in urine, four of which were identified. The major metabolite was 2,5-diiodobenzoic acid (2,5-DIBA). Trace amounts of 2,3-diiodobenzoic acid (2,3-DIBA), o-iodobenzoic acid (OIBA), and iodide ions were detected. 2,3-triiodobenzoic acid (TIBA) is metabolized via deiodination. Iodide ions are accumulated in the thyroid gland and excreted in milk and urine.
Electron capture gas chromatography was used to determine the metabolites of 2,3,5-triiodobenzoic acid in milk following acute administration of 1.197 g of 2,3,5-triiodobenzoic acid. The parent compound and seven suspected metabolites were detected; four were identified and one was quantified. The major metabolite was 2-OHI-3,5-diiodobenzoic acid. Trace amounts of metabolites included monoiodobenzoic acid, 2-OH-5-iodobenzoic acid, and 3,5-diiodobenzoic acid. The highest concentration of 2,3,5-triiodobenzoic acid was observed in the 30-hour milk sample, at 0.79 mg/King; while the highest concentration of 2-OH-3,5-diiodobenzoic acid was observed in the 42-hour milk sample, at 0.27 mg/King.

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Pharmacokinetic data for 2,3,5-Triiodobenzoic acid is derived from plant studies rather than animal models. The compound's molecular weight is 499.81 g/mol. In plants, TIBA is taken up through roots or leaves and distributed through the vascular system. The compound's movement is influenced by its physicochemical properties, including its lipophilicity (due to the three iodine atoms). Metabolism and degradation in plants have been studied in the context of its herbicidal activity.

Non-Human Toxicity Values
Oral LD50 in rats: 813 mg/kg Oral LD50 in mice: 700 mg/kg Intraperitoneal LD50 in mice: 562 mg/kg

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Toxicological data for 2,3,5-Triiodobenzoic acid is available from its use as an agricultural chemical. As with all iodinated compounds and chemical reagents, standard laboratory safety precautions should be observed when handling this compound. The compound should be handled with appropriate personal protective equipment. Its use as a herbicide and defoliant is regulated in agricultural settings. Comprehensive toxicological evaluation has been conducted to support its agricultural applications.

2,3,5-Triiodobenzoic acid is a type of benzoic acid compound whose structure involves replacing the hydrogen atoms at positions 2, 3, and 5 of the benzoic acid molecule with iodine atoms. It is an inhibitor of auxin polar transport and belongs to the class of anti-auxin compounds. It is an organic iodine compound and also a member of the benzoic acid family.

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2,3,5-Triiodobenzoic acid (TIBA) is a plant growth regulator, defoliant, and agricultural herbicide. It is a non-competitive polar auxin transport inhibitor that inhibits and promotes endoreduplication. No clinical trials or regulatory approvals exist for therapeutic use of this compound. It is commercially available from various chemical suppliers for research purposes only. The compound's primary value lies in its utility as a research tool for studying auxin transport and plant development, as well as its agricultural applications. It is also used as an intermediate in the preparation of pharmaceuticals, pesticides, and dyes, and in the synthesis of functional materials.

C7H3I3O2

499.81

499.726

88-82-4

17274-12-3 (hydrochloride salt)

6948

White to off-white amorphous powder
Prisms from alcohol

3.0±0.1 g/cm3

456.7±45.0 °C at 760 mmHg

225 °C

230.0±28.7 °C

0.0±1.2 mmHg at 25°C

1.800

3.87

1

2

1

12

186

0

O=C(C1C(I)=C(I)C=C(I)C=1)O

ZMZGFLUUZLELNE-UHFFFAOYSA-N

InChI=1S/C7H3I3O2/c8-3-1-4(7(11)12)6(10)5(9)2-3/h1-2H,(H,11,12)

2,3,5-triiodobenzoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)