Absorption, Distribution and Excretion
This study investigated the plant metabolism of maize. Soil application of (triazolinone-3-(14)C)Amicarbazone was performed at a rate 1.6 times the maximum seasonal application rate. Application was done before maize sowing, specifically 4 hours after sowing in greenhouse containers. The total radioactive residues (TRR) in maize feed, forage, and grains were 0.988, 2.369, and 0.054 ppm, respectively, with a pre-harvest interval (PHI) of 104 to 126 days. Total extractable residues accounted for 91% to 100% of the TRR. Residues were characterized/identified primarily by high-performance liquid chromatography (HPLC) and confirmed by thin-layer chromatography (TLC) and liquid chromatography-mass spectrometry (LC/MS). Residues identified in maize products accounted for 74% to 79% of the TRR. The parent Amicarbazone was the main residue detected in forage and feed, but less abundant in grains. The primary residue detected in cereals was the metabolite iPr-2-OH DA MKH 3586, which was also detected in forage and feed. Other detected residues included DA MKH 3586, 4-N-glu-DA MKH 3586, and iPr-2-O-glu-DA MKH 3586 (present in cereals, forage, and feed); and tBu-iPr-2-diOH DA MKH 3586 (present only in forage). Four additional glucose/glucoside conjugates were identified in feed at low levels (≤5% TRR). …A trial involving 23 maize fields, each with three application regimens: one pre-planting broadcast, one pre-planting mix (both at 0.45 lb active ingredient/acre), and one early post-planting application (0.25 lb active ingredient/acre). All applications were performed using ground application equipment. Although the early post-sowing application rate was the lowest among the three application regimens, it resulted in the highest total residues of Amicarbazone and its metabolites DA MKH 3586 and iPr-2-OH DA MKH 3586; the residues after pre-sowing compounding were slightly higher than those after pre-sowing application. The highest total residues were found in forage grass at 0.56 ppm, straw at 0.43 ppm, and field corn kernels at approximately 0.05 ppm. …(triazolinone-3-(14)C)Amicarbazone… was administered orally to two lactating goats at an average dietary concentration of 101 ppm (equivalent to 42 times the maximum theoretical dietary load for dairy cows). The goats were administered the drug once daily for three consecutive days. Milk was collected twice daily during the study period, and tissues (muscle, fat, liver, and kidneys) were collected at euthanasia. The highest radioactive residues were found in the liver and kidneys of meat by-products, followed by muscle, fat, and milk… The total residues detected in goat tissues accounted for 91% to 99% of the TRR. Both the parent Amicarbazone and its metabolite DA Amicarbazone were major residues; Amicarbazone was a major residue in all tissues except the kidneys. The metabolite iPr-2-OH DA Amicarbazone was found in higher concentrations in the kidneys but lower concentrations in all other matrices. The metabolite t-Bu-OH MKH 3586 was also identified as a major residue in milk, muscle, and kidneys, but lower concentrations in fat and liver. The metabolite iPr-Ene DA MKH 3586 was found in higher concentrations in the liver but lower concentrations in all other matrices. The TRR of other identified metabolites was ≤ 9%. These compounds include triazolinone MKH 3586, triazolinone DA MKH 3586, tert-butyric acid MKH 3586, tert-butylisopropyl-2-dihydroxy DA MKH 3586 (kidney and liver only), isopropyl-1,2-dihydroxy DA MKH 3586, and tert-butyl-hydroxy DA MKH 3586. The encapsulated Amicarbazone was orally administered to lactating cows for 30 days. The concentrations of Amicarbazone added to the cow diets were 0.374, 1.238, or 4.538 ppm. Milk samples were collected twice daily… Muscle, liver, kidney, and fat samples were collected at slaughter. In whole milk samples collected during the high-dose administration period, Amicarbazone-related residues were below the method limit of quantitation (LOQ; <0.010 ppm). …Amicarbazone-related residues were highest in the liver and kidneys, and lower in the muscle and fat. In the high-dose group, residues in the liver ranged from 1.165 to 1.193 ppm, in the kidney from 0.080 to 0.127 ppm, in muscle from 0.014 to 0.021 ppm, and in fat from less than 0.010 to 0.012 ppm. …In the medium-dose and low-dose groups, liver residues ranged from 0.305 to 0.440 ppm and 0.191 to 0.235 ppm, respectively, while kidney residues ranged from 0.033 to 0.039 ppm and 0.017 to 0.018 ppm, respectively. Residues in muscle and fat samples from the medium-dose group were below the limit of quantitation (LOQ)…Residues related to Amicarbazone in the liver and kidneys showed a linear relationship with the administered level.
For more complete data on the absorption, distribution, and excretion of Amicarbazones (7 in total), please visit the HSDB record page.

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Metabolism/Metabolites
In a rat metabolism study…(triazolinone-3 (14)C) MKH 3586 (Amicarbazone…radiochemical purity > 99%) was dissolved in water and administered by gavage to four male Fischer rats at doses ranging from 5.25 to 5.99 mg/kg…72 hours after administration, the overall recovery rate of the radioactive dose was 95%. The majority of the dose was recovered in urine within 24 hours (64% of the dose), indicating significant absorption. Within 24 hours after administration, 27% of the total dose was excreted in feces. After 24 hours, only 2% of the dose was recovered in feces…72 hours after administration, the radioactive concentrations in selected tissues were low (0.004 to 0.073 μg/g). High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to identify the parent compound and its nine metabolites in the feces of male rats… The compounds identified in the feces accounted for 74% of the total dose… Small amounts of the parent compound were detected in both urine (approximately 2% of the total dose) and feces (<1%). The major metabolite in feces was the hydroxylated deamination derivative of the parent compound, iPr-2-OH DA (34% of the total dose), which was mainly present in urine (32% of the total dose). Other hydroxylated deamination derivatives were also identified: tBu-OH DA (11% of the dose in urine and 4% in feces) and iPr-1,2-di-OH DA (6% of the dose in urine and <1% in feces). The glucuronide conjugate of the parent compound MKH 3586 GA accounted for 11% of the dose and was mainly present in feces (10% of the dose). Other metabolites identified in excrement (each ≤3%) included: tBu-1,2-di-iPr-tri-OH DA; tBu-iPr-di-OH DA; iPr-1,3-diOH DA; tBu-OH-iPr-ene and DA. According to the metabolomic profile, the metabolism of MKH 3586 in male rats mainly involves deamination followed by hydroxylation, and is eventually excreted in the urine. The parent drug is also glucuronidated and excreted in the feces. In a rat metabolism study… (triazolinone-3-(14)C)4-methylMKH 3586 (a soil metabolite of Amicarbazone… radiochemical purity >99%) was dissolved in water and administered by gavage to four male Fischer rats at doses ranging from 4.86 to 5.22 mg/kg… 96 hours after administration, the overall recovery rate of the radioactive dose was 91%. Most of the dose was excreted in the urine within 12 hours (70% of the dose), with total urinary excretion accounting for 80% of the dose, indicating significant absorption. Fecal excretion (0 to 24 hours post-administration) accounted for 8% of the dose. Approximately 3% of the dose was recovered from the excrement 24 hours after administration… At 96 hours post-administration, the radioactivity concentrations in tissues were low (0.002 to 0.028 μg/g), with doses in all tissues below 0.1%. High-performance liquid chromatography (HPLC), ¹H-NMR, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses identified 12 components in the excrement… Four of these compounds were present in chiral pairs. The identified compounds represented 75% of the administered dose… The overall recovery rate of the administered dose was approximately 82%… The test substance was not detected in urine or feces. Soil metabolites undergo hydroxylation at the isopropyl group to produce the major metabolite 4-methylisopropyl-2-hydroxyDA MKH 3586 (29% of the administered dose), which is primarily found in urine (28% of the administered dose). Further hydroxylation of the tert-butyl group yields 4-Me-t-Bu-iPr-2-di-OH DA MKH 3586, accounting for 12% of the dose. Alternatively, further hydroxylation of the isopropyl group yields 4-Me-iPr-1,2-di-OH DA MKH 3586, accounting for 9% of the urinary dose. Demethylation of the parent compound yields DA MKH 3586 (<1% of the dose), and hydroxylation of its isopropyl group yields iPr-2-OH DA MKH 3586 (8% of the dose). The tert-butyl moiety of the parent compound also undergoes hydroxylation to generate 4-Me-tBu-OH DA MKH 3586 (9% dose), which was detected only in urine. Other minor metabolites are typically products of further oxidation (usually hydroxylation). The metabolic pathway of 4-methyldopamine MKH 3586 in rats primarily involves a series of hydroxylation reactions. No conjugates were detected. /4-MethylMKH 3586 (soil metabolite of urea)/
...Residues of concern in plants and livestock include urea (4-amino-N-(1,1-dimethylethyl)-4,5-dihydro-3-(1-methylethyl)-5-oxo-1H-1,2,4-triazole-1-carboxamide), deamination metabolite /(DA urea: N-(1,1-dimethylethyl)-4,5-dihydro-3-(1-methylethyl)-5-oxo-1H-1,2,4-triazole-1-carboxamide)/, and the hydroxylated derivative of the latter /(iPr-2-OH DA urea: N-(1,1-dimethylethyl)-4,5-dihydro-3-(1-hydroxy-1-methylethyl)-5-oxo-1H-1,2,4-triazole-1-carboxamide). Deamination metabolites and their N-methyl derivatives are also included in the drinking water assessment…
/Speculated/ The main metabolic pathway in maize involves the deamination of the triazole amino group to generate the deamination metabolite (DA MKH 3586), followed by tertiary carbon hydroxylation of the isopropyl group to generate iPr-2-OH DA MKH 3586. Other pathways involve hydroxylation of the isopropyl methyl group to generate iPr-1-OH DA MKH 3586, followed by glycosylation; tert-butyl and isopropyl hydroxylation to generate tBu-iPr-2-diOH DA MKH 3586. Furthermore, DA MKH 3586 generates N-glycosides; hydroxylated DA MKH 3586 is glycosylated to generate several small amounts of O-glycosides.
For more metabolite/metabolite (complete) data for AMICARBAZONE (10 metabolites in total), please visit the HSDB record page.

Weed Science 57(6):579-583. 2009

Amicarbazone belongs to the triazole class of compounds. Its chemical name is 4,5-dihydro-1H-1,2,4-triazol-5-one, with a tert-butylaminocarbonyl group substituted at the 1-position and an isopropyl group substituted at the 3-position. It is a selective herbicide used for pre- and post-emergence control of annual dicotyledonous and grassy weeds, but it has not been approved for use in the European Union. It has some herbicidal activity. It belongs to the triazole and carbazide classes of compounds.

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Mechanism of Action
In a mechanistic subchronic oral toxicity study, MKH 3586 (aminocarbazone; ≥98% ai…) was added to feed at dose levels of 0, 50, 1250, or 2500 ppm (equivalent to 0/0, 0.8/0.6, 19.4/13.5, or 40.0/28.8 mg/kg/day for males/females) for 10 weeks. In addition, five male and five female rats in each group were fed experimental diets containing 0 and 2500 ppm of TSH for 10 weeks, followed by a 4-week recovery period… In female rats in the 1250 ppm group, TSH, free T3, T4, free T4, and T4 levels increased by 27% to 61%. In female rats in the 2500 ppm group, these thyroid hormone levels increased by 5% to 24% compared to the control group (the difference was not statistically significant), but the increase was less than that in the 1250 ppm group. In male rats in the 2500 ppm group, T3 (increased by 52%) and free T3 (increased by 31%; the difference was not statistically significant) levels were increased. At the end of the recovery period, the TSH, T3, and T4 levels in both male and female rats in the 2500 ppm group were comparable to those in the control group. In perchlorate assays, the ratio of thyroid to blood (125)I in the MKH 3586 treatment group was comparable to that in both males and females in the negative control group, indicating that the increase in thyroid hormones was not due to increased synthesis… No treatment-related changes in thyroid weight or thyroid microstructure were observed at any dose. In the liver, UDP-GT activity increased by 109% to 241% in both males and females in the ≥1250 ppm dose group, and remained at a 27% increase in females in the 2500 ppm dose group at the end of the recovery period. The absolute/relative liver weight (relative to body weight) increased in males (9/14%) and females (5/12%) in the ≥1250 ppm dose group, and in males (25/32%) and females (18/31%) in the 2500 ppm dose group. At the end of the recovery period, the relative liver weight of males in the 2500 ppm group remained increased (7%). At the end of the recovery period, the absolute liver weight in males and both the absolute and relative liver weight in females were comparable to those in the control group. Since the test substance is primarily metabolized via glucuronidation of UDP-GT, it is hypothesized that MKH 3586 competitively inhibited the glucuronidation of T3 and T4 by UDP-GT at a concentration of 1250 ppm, leading to elevated serum levels of these thyroid hormones. At a concentration of 2500 ppm, further induction of UDP-GT began to compensate for this competitive inhibition, resulting in a decrease in T3 and T4 levels. In females, at concentrations ≥1250 ppm, final body weight decreased by 7% to 10%...at a concentration of 2500 ppm, body weight still decreased by 8% at the end of the recovery period. An increased amount of food spillage was observed at a concentration of 2500 ppm. Daily food consumption per animal decreased intermittently by 3% to 16% (p ≤ 0.05) in the following cases: (i) male animals treated at a concentration of 2500 ppm; (ii) female animals treated at a concentration ≥ 1250 ppm; and (iii) female animals treated at a concentration of 2500 ppm at the end of the recovery period. There were no significant differences between groups in daily food consumption per kilogram of animal. Both absolute and relative uterine weight decreased in animals treated at 1250 ppm and 2500 ppm (15%/9% and 24%/15%, respectively). In animals treated at 2500 ppm during the recovery period, the decrease in absolute uterine weight (20%) and relative uterine weight (13%; not statistically significant) continued. Treatment had no effect on the number of estrous cycles. However, at a concentration of 2500 ppm, a slight increase in estrous cycle duration of 4% was observed. In summary, female animals with concentrations ≥1200 ppm and male animals with concentrations ≥2500 ppm exhibited elevated thyroid hormone levels. However, the thyroid/blood iodine-125 ratio in the treated groups was comparable to that in the negative control group, indicating that thyroid hormone synthesis was not impaired. Therefore, the difference in thyroid hormone levels must have been due to extrathyroidal metabolism. Based on increased liver weight and UDP-glucuronyl transferase activity, the liver was considered the site of origin.
... The possible interactions of MKH 3586 (aminocarbazone; 98.2% ai ...), MKH 3594 (N-deamination metabolite; 99.4% ai ...), and KOK 9422 (specified hydrolytic metabolite; 100% ai ...) with enzymes involved in thyroid hormone synthesis and the regulation of the hypothalamic-pituitary-thyroid axis were investigated using three in vitro systems: (i) thyroid peroxidase (TPO), a key enzyme responsible for iodine organification and coupling of iodinated tyrosine residues with T3 and T4; (ii) iodothyronine deiodinase type I (ID-I), which catalyzes the deiodination of the phenolic ring of T4 to T3 and is present in peripheral organs such as the thyroid, liver, and kidneys; and (iii) iodothyronine deiodinase type II (ID-II), which catalyzes the deiodination of the phenolic ring of T4 to T3 and is present in the hypothalamus and pituitary gland. The positive control demonstrated the sensitivity of each in vitro detection method through potent, concentration-dependent inhibition of the target enzyme… MKH 3586, MKH 3594, and KOK 9422 did not inhibit TPO, ID-I, or ID-II at concentrations up to 1 mM, indicating that MKH 3586 does not affect the iodide organification step in thyroid hormone synthesis (whether by inhibiting TPO or capturing iodine), nor does it affect the peripheral metabolism of thyroid hormones in vivo via type I or type II deiodinases. These findings support the conclusion that MKH 3586 does not affect the major enzymes involved in thyroid hormone synthesis or regulation, and are consistent with… the results of subchronic mechanism studies in rats…
Amicarbazone exhibits herbicidal activity against annual broadleaf weeds. It selectively inhibits acetyllactone synthase, an enzyme involved in plant photosystem II.

C10H19N5O2

241.29016

241.153

129909-90-6

153920

Colorless crystals

1.3±0.1 g/cm3

137.5ºC

1.587

-0.99

2

4

2

17

369

0

O=C(N1N=C(C(C)C)N(N)C1=O)NC(C)(C)C

ORFPWVRKFLOQHK-UHFFFAOYSA-N

InChI=1S/C10H19N5O2/c1-6(2)7-13-15(9(17)14(7)11)8(16)12-10(3,4)5/h6H,11H2,1-5H3,(H,12,16)

4-amino-N-tert-butyl-5-oxo-3-propan-2-yl-1,2,4-triazole-1-carboxamide

BAY-314666; BAY-MKH 3586; BAY314666; BAYMKH 3586; BAY 314666; BAY MKH 3586

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

H2O : ~1 mg/mL (~4.14 mM)

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.)