Metabolism / Metabolites
Trimethyldiketone's known metabolites include dimethyldiketone.

Toxicity Summary
Diketoacids reduce T-type calcium currents in thalamic neurons, including thalamic relay neurons, by inhibiting voltage-dependent T-type calcium channels. This raises the threshold for repetitive thalamic activity and inhibits corticothalamic transmission. Consequently, the abnormal thalamic cortical rhythmicity thought to be associated with 3 Hz spike-and-wave discharges observed on absence seizure EEG is diminished.

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Protein Binding
90%

[1]. Synthesis and anticonvulsant activity of bioisosteres of trimethadione, N-derivative-1,2,3-oxathiazolidine-4-one-2,2-dioxides from α-hydroxyamides. Bioorg Med Chem. 2013 Feb 15;21(4):841-6.

[2]. The antihyperalgesic effects of the T-type calcium channel blockers ethosuximide, trimethadione, and mibefradil. Eur J Pharmacol. 2005 Oct 3;521(1-3):79-85.

Trimethadione may cause developmental toxicity depending on state or federal labeling requirements. Trimethadione is an oxazolidinone drug with the structure 1,3-oxazolidin-2,4-dione, substituted with methyl groups at positions 3, 5, and 6. It is an antiepileptic drug with anti-aging and anticonvulsant effects. It is an anticonvulsant effective for absence seizures, but due to its toxicity, it is usually used only in refractory cases. (Excerpt from JAMA Drug Evaluation Yearbook, 1994, p. 378) Trimethadione is an antiepileptic drug. The physiological action of trimethadione is achieved by reducing disordered electrical activity in the central nervous system. Trimethadione is a diketone anticonvulsant with antiepileptic activity. Trimethadione reduces T-type calcium currents in thalamic neurons, thereby stabilizing the neuronal membrane, increasing the threshold for repetitive thalamic activity, and inhibiting corticothalamic transmission. This reduces abnormal thalamic cortical rhythms, which are thought to be the basis of the paroxysmal three-cycle-per-second spike-and-wave pattern that appears in absence seizures (petit mal seizures). Trimethadione is only found in individuals who have used or taken this drug. It is an anticonvulsant effective for absence seizures, but due to its toxicity, it is usually used only in refractory cases. (From JAMA Drug Evaluation Yearbook, 1994, p. 378) Trimethadione reduces T-type calcium currents in thalamic neurons, including thalamic relay neurons. Its mechanism of action is through inhibition of voltage-dependent T-type calcium channels. This raises the threshold for repetitive thalamic activity and inhibits corticothalamic transmission. Therefore, the abnormal thalamic cortical rhythms thought to be associated with 3 Hz spike-and-wave discharges observed on absence seizure EEG are suppressed.
An antiepileptic drug effective for absence seizures, but due to its toxicity, it is usually used only in refractory cases. (Excerpt from JAMA Drug Evaluation Yearbook, 1994, p. 378) Drug Indications For the control of absence seizures (petit mal seizures) unresponsive to other drug treatments. Mechanism of Action Diketone antiepileptic drugs reduce T-type calcium currents in thalamic neurons (including thalamic relay neurons) by inhibiting voltage-dependent T-type calcium channels. This increases the threshold for repetitive thalamic activity and inhibits corticothalamic transmission. Therefore, the abnormal thalamic cortical rhythmicity thought to be associated with 3 Hz spike-and-wave discharges observed on absence seizure EEG is suppressed. Pharmacodynamics Methyldione and trimethyldione are anticonvulsants indicated for the control of absence seizures (petit mal seizures) unresponsive to other drug treatments. Diketone anticonvulsants are used to treat epilepsy. They act on the central nervous system (CNS) to reduce the frequency of seizures.

C6H9NO3

143.142

143.058

127-48-0

5576

White to off-white solid powder

1.171g/cm3

78-80°C 5mm

45-46°C

78-80°C/5mm

2.98mmHg at 25°C

1.457

0.311

0

3

0

10

197

0

IRYJRGCIQBGHIV-UHFFFAOYSA-N

InChI=1S/C6H9NO3/c1-6(2)4(8)7(3)5(9)10-6/h1-3H3

3,5,5-trimethyl-1,3-oxazolidine-2,4-dione

Trimetin; Trimethadione; Tridione

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)

DMSO : ≥ 40 mg/mL (~279.45 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (17.47 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (17.47 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (17.47 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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