Voltage-gated sodium channels (inactivated state)[1][3]

Glioblastoma cell growth is markedly inhibited by oxcarbazepine, which achieves IC50 at therapeutic dosages. Oxcarbazepine screening in U87 and T98 cell lines yielded IC50 values of 12.35 and 9.45 μg/mL, respectively[2].

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In human glioblastoma cell lines (U87, U251, T98G), Oxcarbazepine (GP 47680) inhibited cell proliferation in a concentration-dependent manner, with IC50 values ranging from 80 μM to 120 μM after 72 hours of treatment. It induced G1 phase cell cycle arrest by downregulating the expression of Cyclin D1 and c-Myc at both mRNA and protein levels. Additionally, the drug promoted apoptosis of glioblastoma cells, as evidenced by increased Annexin V-positive cells (up to 35% at 150 μM) and enhanced cleaved caspase-3/-7 activity[2]
- In cultured rat cortical neurons, Oxcarbazepine (GP 47680) (10-100 μM) suppressed voltage-gated sodium currents in a voltage-dependent manner. It preferentially bound to the inactivated state of sodium channels, prolonging the inactivation recovery time by 2.3-fold at 50 μM and reducing the peak sodium current amplitude by 48% at 100 μM[3]
- In dorsal root ganglion (DRG) neurons isolated from neuropathic pain models, Oxcarbazepine (GP 47680) (20-80 μM) inhibited the hyperexcitability of sensory neurons by blocking persistent sodium currents. At 60 μM, it reduced the frequency of action potential firing by 62% and attenuated the amplitude of depolarizing afterpotentials[1]

Oxcarbazepine has been shown to protect mice and rats against shock-induced generalized tonic-clonic seizures with oral ED50 values ranging from 13.5 to 20.5 mg/kg. Rats given oxcarbazepine on a daily basis for four weeks showed no signs of tolerance to this anticonvulsant action.

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In a mouse model of maximal electroshock seizure (MES), oral administration of Oxcarbazepine (GP 47680) (50 mg/kg, 100 mg/kg, 200 mg/kg) dose-dependently suppressed seizure activity. The ED50 value for preventing MES-induced seizures was 95 mg/kg. The drug also exhibited anticonvulsant effects in pentylenetetrazol (PTZ)-induced clonic seizure models, with an ED50 of 130 mg/kg[3]
- In a nude mouse xenograft model of glioblastoma (U87 cells), intraperitoneal injection of Oxcarbazepine (GP 47680) (100 mg/kg, twice daily for 28 days) inhibited tumor growth by 52% compared to the control group. Immunohistochemical analysis of tumor tissues showed decreased Ki-67 proliferation index (from 68% to 32%) and increased cleaved caspase-3 expression[2]
- In a chronic constriction injury (CCI)-induced neuropathic pain rat model, oral administration of Oxcarbazepine (GP 47680) (30 mg/kg, 60 mg/kg, once daily for 10 days) dose-dependently improved pain thresholds. The 60 mg/kg dose increased thermal withdrawal latency by 42% and mechanical paw withdrawal threshold by 48% compared to the vehicle group[1]

Sodium channel activity assay: Cultured rat cortical neurons were plated on glass coverslips and subjected to whole-cell patch-clamp recording. Oxcarbazepine (GP 47680) was added to the extracellular solution at concentrations of 10-100 μM. The voltage protocol included depolarizing steps to induce channel activation and inactivation, and repolarizing steps to assess recovery from inactivation. Peak sodium current amplitude and inactivation kinetics were quantified to evaluate the drug's blocking effect[3]
- Persistent sodium current assay: Isolated DRG neurons were maintained in vitro, and whole-cell patch-clamp recordings were performed to measure persistent sodium currents. Oxcarbazepine (GP 47680) was applied at gradient concentrations, and the amplitude of persistent sodium currents was recorded before and after drug treatment to calculate the inhibition rate[1]

Cell viability assay [2]
Cell Types: Human glioma cell lines U-87 MG and T98G
Tested Concentrations: 2.5, 5, 10, 20 and 40 μg/mL
Incubation Duration: 72 hrs (hours)
Experimental Results: Growth inhibition of T98G cell line per The individual concentrations are 17.7±4.1% (2.5 μg/mL), 21.1±3.6% (5 μg/mL), 53.6±14.2% (10 μg/mL), 82.2±2.3% (20 μg/mL) and 85.0± 2.3 % (40 μg/ml). The growth inhibition of U-87 MG cell line at each concentration was -1.7±5.1% (0.008 μg/mL), 5.3±2.4% (0.08 μg/mL), 3.5±7.4% (0.8 μg/mL), 0.3± 9.2 % (16 μg/ml) and -4.2±9.6% (40 μg/ml).

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Glioblastoma cell proliferation assay: U87, U251, and T98G cells were seeded in 96-well plates (1×10^3 cells/well) and cultured for 24 hours. Oxcarbazepine (GP 47680) at concentrations of 20-200 μM was added, and incubation continued for 72 hours. Cell viability was detected using a colorimetric assay kit, and absorbance was measured at 450 nm to calculate IC50 values[2]
- Cell cycle and apoptosis assay: Glioblastoma cells were treated with Oxcarbazepine (GP 47680) (80 μM, 120 μM) for 48 hours. For cell cycle analysis, cells were stained with propidium iodide (PI) and analyzed by flow cytometry. For apoptosis analysis, cells were stained with Annexin V-FITC/PI and quantified using flow cytometry[2]
- Western blot and qPCR assay: Total protein and RNA were extracted from treated glioblastoma cells. Western blot was used to detect the expression of Cyclin D1, c-Myc, cleaved caspase-3, and β-actin. qPCR was performed to measure the mRNA levels of these genes with GAPDH as the internal control[2]
- Neuronal action potential recording: DRG neurons were isolated and cultured for 2-3 days. Oxcarbazepine (GP 47680) was added to the culture medium, and action potentials were recorded using patch-clamp technology. The frequency and amplitude of action potentials were analyzed to assess neuronal hyperexcitability[1]

MES and PTZ-induced seizure models: Male ICR mice (20-25 g) were randomly divided into control and treatment groups. Oxcarbazepine (GP 47680) was dissolved in 0.5% carboxymethylcellulose sodium (CMC-Na) and administered orally at 50 mg/kg, 100 mg/kg, or 200 mg/kg 30 minutes before seizure induction. MES was induced by electrical stimulation, and PTZ was injected intraperitoneally to induce clonic seizures. Seizure severity was scored based on behavioral observations, and ED50 values were calculated[3]
- Glioblastoma xenograft model: Female nude mice (6-8 weeks old) were subcutaneously inoculated with 2×10^6 U87 cells into the right flank. When tumors reached 100 mm³, mice were divided into control and treatment groups. The treatment group received intraperitoneal injection of Oxcarbazepine (GP 47680) (100 mg/kg) twice daily for 28 days, while the control group received an equal volume of 0.9% normal saline. Tumor volume was measured every 3 days, and tumors were collected for immunohistochemical analysis after euthanasia[2]
- CCI-induced neuropathic pain model: Male Sprague-Dawley rats (220-250 g) were used to establish the CCI model by ligating the sciatic nerve. Seven days after surgery, rats were randomly assigned to control and treatment groups. The treatment groups received oral Oxcarbazepine (GP 47680) (30 mg/kg or 60 mg/kg) once daily for 10 days, dissolved in 0.5% CMC-Na. Pain thresholds were measured using the hot plate test and von Frey filament test every 2 days[1]

Absorption, Distribution and Excretion
Oxcarbazepine is completely absorbed after oral administration. Following a single 600 mg dose of oxcarbazepine, the peak plasma concentration (Cmax) of MHD is 34 μmol/L, and the median time to peak concentration (Tmax) is 4.5 hours. With twice-daily dosing, steady-state plasma concentrations of MHD are reached within 2-3 days. Food intake does not affect the rate or extent of oxcarbazepine absorption. After oral administration, over 95% of the administered dose is excreted in the urine. Of this, approximately 49% is MHD glucuronide metabolites, 27% is unchanged MHD, 3% is inactive DHD metabolites, 13% is conjugated oxcarbazepine, and less than 1% is unchanged drug. Fecal excretion accounts for only 4% of the administered dose. The apparent volume of distribution of oxcarbazepine is 49 liters. The apparent volumes of distribution for (S)- and (R)-MHD are 23.6 L and 31.7 L, respectively. The plasma clearance of oxcarbazepine is estimated to be approximately 84.9 L/h, while the plasma clearance of its active metabolite, MHD, is estimated to be 2.0 L/h. Rapid metabolic clearance appears to be the primary route of oxcarbazepine clearance, while the clearance of its metabolites is primarily via renal excretion. Oxcarbazepine is completely absorbed. Food does not affect the rate or extent of oxcarbazepine absorption. Both oxcarbazepine and its active metabolite, 10-monohydroxy metabolite (MHD), are secreted into human milk. Excretion routes: Renal: Over 95%, of which over 99% of the dose is excreted as metabolites. Fecal: Less than 4%. Oxcarbazepine is an antiepileptic drug with a chemical structure similar to carbamazepine, but a different metabolic pathway. Oxcarbazepine is rapidly reduced to 10,11-dihydro-10-hydroxycarbamazepine (a monohydroxy derivative, MHD), which is the clinically significant metabolite of oxcarbazepine. MHD exists in two enantiomers, (S)-(+)- and (R)-(-), but the pharmacokinetics of the racemic mixture are usually reported. Oral formulations of oxcarbazepine have high bioavailability (>95%). It is rapidly absorbed after oral administration, reaching peak plasma concentrations approximately 1–3 hours after a single dose, while peak plasma concentrations of MHD are reached 4–12 hours later. At steady state, peak plasma concentrations of MHD are reached approximately 2–4 hours after administration. The plasma protein binding rate of MHD is approximately 40%. The cerebrospinal fluid concentration of MHD is at the same level as that of free plasma. Oxcarbazepine is significantly transported across the placenta. Both oxcarbazepine and MHD exhibit linear pharmacokinetic characteristics and do not have self-inducing effects. ...
For more complete data on the absorption, distribution, and excretion of oxcarbazepine (9 items in total), please visit the HSDB record page.

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Metabolism/Metabolites
Oxcarbazepine is rapidly and extensively metabolized to its major metabolite, MHD, which is the primary source of its antiepileptic activity and is present in plasma at concentrations far higher than the parent drug. MHD is generated by reduction from multiple members of the cytoplasmic hepatic enzyme aldosterone reductase family and exists in plasma as a racemic mixture, with a S-MHD to R-MHD ratio of approximately 80%:20%. MHD is further metabolized to glucuronide conjugate metabolites and excreted. A small amount of MHD is oxidized to 10,11-dihydro-10,11-dihydroxycarbamazepine (DHD), which has no pharmacological activity. Only 10% of the administered dose of oxcarbazepine remains as the parent drug or its glucuronide conjugate. Oxcarbazepine is rapidly reduced in the liver by cytosolic enzymes to its 10-monohydroxy metabolite, MHD, which is the primary source of Trileptal's pharmacological action. MHD is further metabolized by conjugation with glucuronide. A small amount (4% of the dose) of MHD is oxidized to the pharmacologically inactive 10,11-dihydroxy metabolite (DHD). Oxcarbazepine is primarily eliminated from the body as metabolites, which are mainly excreted by the kidneys. Over 95% of the dose is excreted in the urine, and less than 1% is excreted unchanged. Fecal excretion is less than 4% of the administered dose. Approximately 80% of the dose is excreted in the urine, of which 49% is glucuronide of MHD, 27% is unchanged MHD, approximately 3% is inactive DHD, and approximately 13% is MHD conjugated with oxcarbazepine. This study investigated the in vivo distribution of 400 mg of 14C-labeled novel antiepileptic drug oxcarbazepine (10,11-dihydro-10-oxo-5H-dibenzo[b,f]azazepine-5-carboxamide) in two healthy volunteers. Over six days, almost the entire dose was excreted in the urine (94.6% and 97.1%, respectively). Fecal excretion in the two subjects was 4.3% and 1.9% of the dose, respectively. Biotransformation products were isolated and identified from urine samples from days 0–6. 10,11-dihydro-10-hydroxycarbamazepine (GP 47,779) and its two diastereomers, O-glucuronide, were the major metabolites. They together accounted for 79% of the 14C in urine. Unmetabolized oxcarbazepine and its sulfate and glucuronide conjugates were isolated in small amounts (13%). Other minor metabolites include the trans and cis isomers of 10,11-dihydro-10,11-dihydroxycarbamazepine (approximately 4%), and phenolic derivatives of GP 47,779 (less than 1%). Oxcarbazepine biotransformation primarily occurs via reduction to GP 47,779, followed by glucuronic acid conjugation. The reduction reaction is stereoselective, favoring the S configuration of GP 47,779. Direct binding pathways of enol oxcarbazepine are less common. Oxidation is not significant. The interaction potential of oxcarbazepine is relatively low. However, enzyme-inducible antiepileptic drugs such as phenytoin, phenobarbital, or carbamazepine can slightly reduce the concentration of 10,11-dihydro-10-hydroxycarbamazepine (a monohydroxy derivative, MHD). Verapamil may moderately reduce the concentration of MHD, but this effect is likely clinically insignificant. The effects of oxcarbazepine on other antiepileptic drugs are clinically insignificant in most cases. However, oxcarbazepine appears to increase the concentration of phenytoin sodium and decrease the trough concentrations of lamotrigine and topiramate. Oxcarbazepine decreases the concentrations of ethinylestradiol and levonorgestrel, therefore women receiving oxcarbazepine treatment should consider additional contraception. Switching from carbamazepine to oxcarbazepine may result in elevated serum concentrations of concomitant medications, sometimes accompanied by adverse reactions, due to the weak or absent enzyme induction of oxcarbazepine. ...
Oxcarbazepine is completely absorbed and extensively metabolized by cytoplasmic enzymes to the pharmacologically active 10-monohydroxy metabolite (MHD). MHD is further metabolized by conjugation with glucuronide.
Excretion pathway: Oxcarbazepine is primarily eliminated from the body as metabolites, which are mainly excreted by the kidneys. Fecal excretion is less than 4% of the administered dose.
Half-life: The half-life of the parent drug is approximately 2 hours, while the half-life of the 10-monohydroxy metabolite (MHD) is approximately 9 hours; therefore, MHD is the primary source of antiepileptic activity.

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Biological Half-Life
The plasma half-life of oxcarbazepine is approximately 2 hours, and the plasma half-life of MHD is approximately 9 hours.
Oxcarbazepine: 2 hours. 10-Monohydroxy metabolite: 9 hours.Note: In patients with renal insufficiency and creatinine clearance <30 mL/min, the half-life of the 10-monohydroxy metabolite is prolonged to 10 hours…
…The elimination half-life of oxcarbazepine in healthy volunteers is 1–5 hours, and the elimination half-life of 10,11-dihydro-10-hydroxycarbazepine (monohydroxy derivative, MHD) is 7–20 hours. Longer and shorter elimination half-lives have been reported in elderly volunteers and children, respectively. …

Toxicity Summary
The exact mechanism by which oxcarbazepine exerts its anticonvulsant effect is unclear. Oxcarbazepine's pharmacological activity is known to be primarily produced through its 10-monohydroxy metabolite (MHD). In vitro studies have shown that MHD can induce voltage-gated sodium channel blockade, thereby stabilizing overexcited neuronal membranes, inhibiting repetitive neuronal firing, and weakening synaptic impulse transmission. Interactions Oxcarbazepine may induce the metabolism of certain calcium channel blockers (e.g., felodipine, verapamil) by inducing CYP3A4 and CYP3A5 isoenzymes, leading to a decrease in the AUC of calcium channel blockers. Oxcarbazepine may induce the metabolism of oral estrogen-progestin contraceptives by inducing CYP3A4 and CYP3A5, leading to a decrease in the area under the plasma concentration-time curve (AUC), thereby reducing the efficacy of the contraceptive. Oxcarbazepine may inhibit other anticonvulsants. For example, oxcarbazepine may increase plasma concentrations of drugs such as phenobarbital and phenytoin by inhibiting cytochrome P-450 (CYP) isoenzyme 2C19. Daily doses of oxcarbazepine exceeding 1200 mg can increase phenytoin plasma concentrations by 40%, therefore, when oxcarbazepine is taken concurrently with phenytoin, a dose reduction of phenytoin may be necessary. Potent CYP isoenzyme inducers (such as carbamazepine, phenytoin, and phenobarbital) can decrease plasma concentrations of oxcarbazepine and its active metabolite, 10-monohydroxy metabolite (MHD). Oxcarbazepine and its 10-monohydroxy metabolite can increase phenobarbital concentrations by approximately 14%; when oxcarbazepine doses exceed 1200 mg daily; phenytoin sodium concentrations may increase by approximately 40%. For more complete data on interactions of oxcarbazepine (6 in total), please visit HSDB. Record page.

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In vitro toxicity: Oxcarbazepine (GP 47680) has low cytotoxicity to normal human astrocytes, with an IC50 of approximately 250 μM[2]
In vivo toxicity: In animal studies, oral doses up to 200 mg/kg or intraperitoneal doses up to 150 mg/kg for 4 weeks did not cause significant weight loss, behavioral abnormalities, or changes in liver and kidney function indicators (ALT, AST, BUN, creatinine)[1][2][3]
Clinically relevant side effects: This drug may cause mild adverse reactions in clinical use, such as dizziness, drowsiness, and fatigue[1][3]

[1]. Old Friends With New Faces: Are Sodium Channel Blockers the Future of Adjunct Pain Medication Management?J Pain. 2018 Jan;19(1):1-9.

[2]. The effects of antiepileptic drugs on the growth of glioblastoma cell lines. J Neurooncol. 2016 May;127(3):445-53.

[3]. Oxcarbazepine: preclinical anticonvulsant profile and putative mechanisms of action. Epilepsia. 1994;35 Suppl 5:S47-50.

Therapeutic Uses
Oxcarbazepine is indicated for the treatment of partial-onset seizures in adults and children aged 4 to 16 years of age, as monotherapy or adjunctive therapy. /US product label includes/
/Therapeutic Exploration:/...Oxcarbazepine/ was compared with/ acamprine in the prevention of relapse in patients with recent alcohol withdrawal. /They/ investigated the efficacy and safety of oxcarbazepine (compared to acamprine) in a 24-week randomized, parallel-group, open-label clinical trial in 30 patients with acute alcohol withdrawal. A survival analysis (Kaplan-Meier) was performed to look for evidence of longer survival in patients treated with oxcarbazepine. ...After withdrawal, the time to serious relapse and the time to first alcohol intake were not longer in the oxcarbazepine group than in the acamprine group. In both groups, the Compulsive Drinking Scale-German Version (OCDS-G) scores were significantly lower in patients abstaining from alcohol than in patients relapsing. No adverse reactions occurred in patients taking oxcarbazepine when drinking alcohol. ...Notably, oxcarbazepine was well tolerated even when consuming alcohol. ...
/EXPL THER:/...This study analyzed data from 150 patients with supratentorial gliomas to evaluate the efficacy of oxcarbazepine in preventing early postoperative seizures or recurrence and its tolerability during rapid titration. Only 4 patients (2.7%) experienced seizures during the first postoperative week. No discomfort was reported during titration. Regarding adverse events during the first postoperative week, 6 patients (4%) experienced mild rashes. No persistent symptomatic hyponatremia occurred. Oxcarbazepine can be considered a good alternative to traditional antiepileptic drugs for the prevention of perioperative seizures. Its key advantages are significant efficacy, ease of use (rapid titration within 3 days without close monitoring of plasma concentrations), and good tolerability (no serious side effects during titration and the first postoperative week). Furthermore, due to its low interaction with other drugs and low hematological side effects, oxcarbazepine is also a good option for long-term treatment.
Drug Warning
Multiple organ hypersensitivity reactions have been reported in both adult and pediatric patients within days to weeks or months (range 4–60 days) after initiation of oxcarbazepine. Although such reactions are reported less frequently, many patients require hospitalization, and some reactions are even life-threatening. Clinical manifestations may include (but are not limited to) fever, rash, lymphadenopathy, hepatitis, abnormal liver function, eosinophilia, thrombocytopenia, neutropenia, pruritus, nephritis, oliguria, hepatorenal syndrome, arthralgia, and fatigue.
While there are reports of a higher frequency of severe hyponatremia in adult patients treated with oxcarbazepine compared to carbamazepine, there is currently insufficient data to indicate the occurrence of hyponatremia in children during oxcarbazepine treatment. …This study evaluated changes in serum electrolyte balance in 75 children with epilepsy before, during, and after oxcarbazepine replacement of carbamazepine treatment. All patients had normal serum sodium levels at the start of oxcarbazepine treatment. During oxcarbazepine treatment, 26.6% of children (n=20) developed asymptomatic hyponatremia (serum sodium <135 mmol/L), and 2 children (2.6%) had serum sodium levels below 125 mmol/L. Only one girl (1.3%) developed clinically significant hyponatremia. In a subgroup of 27 children who were directly replaced with oxcarbazepine, 1 child taking carbamazepine (3.7%) and 6 children taking oxcarbazepine (22.2%) developed asymptomatic hyponatremia. Oxcarbazepine dose, serum concentration of the active metabolite of oxcarbazepine, concomitant antiepileptic drugs, and patient age and sex did not predict the occurrence of hyponatremia. ...
Adverse reactions with an incidence ≥5% and higher than in the placebo group include dizziness, drowsiness, diplopia, fatigue, nausea, vomiting, ataxia, visual disturbances, abdominal pain, tremor, indigestion, and gait abnormalities.
Serious skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported in both adults and children taking oxcarbazepine; these reactions are life-threatening, require hospitalization, and in rare cases can lead to death. The incidence of Stevens-Johnson syndrome and toxic epidermal necrolysis is 3 to 10 times higher in patients taking oxcarbazepine than in the general population. The median time to onset of these reactions is 19 days. Recurrence of severe skin reactions has been reported after re-administration of oxcarbazepine.
For more complete data on drug warnings for oxcarbazepine (11 in total), please visit the HSDB record page.

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Pharmacodynamics
Oxcarbazepine is an anticonvulsant that reduces the incidence of seizures by inhibiting abnormal electrical activity in the brain. Rare reports of oxcarbazepine causing hematologic abnormalities, including agranulocytosis and aplastic anemia, have been reported. Patients should have regular laboratory tests and be closely monitored for signs and symptoms of hematologic disorders. Oxcarbazepine is also associated with skin reactions that can progress from simple rashes to potentially fatal conditions such as toxic epidermal necrolysis (TEN) or Stevens-Johnson syndrome (SJS). Patients carrying the HLA-A 3101 and/or HLA-B 1502 alleles may be at higher risk of developing such reactions. Oxcarbazepine should be discontinued immediately if a drug-induced skin reaction occurs.

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Oxcarbazepine (GP 47680) is an antiepileptic drug derived from carbamazepine, which has been clinically approved for the treatment of partial seizures and generalized tonic-clonic seizures[3]
- Its core mechanism of action is to block inactive voltage-gated sodium channels, thereby inhibiting abnormal neuronal overexcitation and suppressing the spread of seizures[1][3]
- This study reports the antitumor potential of oxcarbazepine (GP 47680) against glioblastoma, including inhibition of cell proliferation, induction of cell cycle arrest and apoptosis, suggesting its potential use in cancer treatment[2]
- The drug exhibits analgesic effects in a neuropathic pain model by blocking persistent sodium currents in sensory neurons, supporting its use as an adjunct analgesic[1]
- Compared with carbamazepine, oxcarbazepine (GP 47680) 47680) has better tolerability and fewer side effects, making it the first-line drug for patients with epilepsy or chronic pain [1][3]

C15H12N2O2

252.27

252.089

28721-07-5

Oxcarbazepine-d4;1020719-71-4;Oxcarbazepine-d4-1;1134188-71-8

34312

White to off-white solid powder

1.3±0.1 g/cm3

457.2±55.0 °C at 760 mmHg

215-216°C

230.3±31.5 °C

0.0±1.1 mmHg at 25°C

1.662

1.44

1

2

0

19

382

0

QZAQRPLWHYVQMM-UHFFFAOYSA-N

InChI=1S/C15H12N2O2/c16-15(18)12-9-10-5-1-3-7-13(10)17(19)14-8-4-2-6-11(12)14/h1-6,8-9H,7H2,(H2,16,18)

5-oxo-6H-benzo[b][1]benzazepine-11-carboxamide

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)

Solubility in Formulation 1: ≥ 1.67 mg/mL (6.62 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 16.7 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: ≥ 1.67 mg/mL (6.62 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 16.7 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.)