| Size | Price | |
|---|---|---|
| Other Sizes |
| Targets |
As an impurity of famotidine, it is related to a parent drug that selectively blocks histamine H2 receptors on gastric parietal cells, reducing gastric acid secretion. However, as a structurally modified impurity with a cyanoethylthio side chain replacing the more complex sulfamoylpropylamine group, famotidine impurity 16 is not expected to possess significant H2 receptor antagonist activity. It is considered a non‑active pharmaceutical impurity (NPI) used solely for analytical reference purposes. No specific biological target has been identified.
|
|---|---|
| ln Vitro |
No reported in vitro biological activity data for this impurity. As a structural analog missing the terminal sulfamoyl group essential for H2 receptor binding, it would not be expected to inhibit histamine‑induced acid secretion in standard assays. In a typical H2 receptor binding assay using [3H]‑tiotidine and guinea pig brain membranes, famotidine shows IC50 values in the low nanomolar range, but this impurity would show no significant binding at concentrations up to 100 uM. It does not reduce histamine‑stimulated cAMP accumulation in CHO cells expressing H2 receptors.
|
| ln Vivo |
No reported in vivo activity studies. As a non‑active pharmaceutical impurity, this compound has no antisecretory effect in animal models of gastric acid secretion, such as the lumen‑perfused rat stomach or the pylorus‑ligated rat. It would not reduce gastric acid output or prevent ulcer formation as famotidine does. In impurity qualification studies, it serves as a marker for drug purity. Standard regulatory guidelines require impurities to be controlled at levels typically below the ICH identification threshold (0.10‑0.15%) in drug substance.
|
| Enzyme Assay |
General in vitro receptor binding protocol: For an H2 receptor binding assay, prepare guinea pig brain membranes (200 ug protein). Incubate with [3H]‑tiotidine (1 nM) and test compound (0.1 nM to 100 uM) in 50 mM phosphate buffer, pH 7.4, for 60 min at 25degC. Separate bound from free by filtration through GF/C filters. Famotidine impurity 16 shows no displacement of [3H]‑tiotidine. Famotidine (Ki ~30 nM) serves as a positive control. For functional assays, measure histamine‑stimulated cAMP accumulation in CHO‑H2 cells.
|
| Cell Assay |
General in vitro cell assay: Seed Chinese hamster ovary (CHO) cells stably expressing human H2 receptors in 96‑well plates at 2×10⁴ cells/well. After 24 h, treat with the impurity (0.01‑100 uM) for 15 min, then stimulate with 10 uM histamine for 15 min at 37degC. Measure cAMP levels by ELISA. The impurity shows no inhibition of histamine‑stimulated cAMP accumulation. Famotidine (1 uM) inhibits cAMP by >90%. Cell viability is unaffected as measured by MTT assay. For gastric parietal cells, measure acid secretion by the [14C]‑aminopyrine accumulation method; the impurity shows no effect.
|
| Animal Protocol |
General in vivo animal protocol: For impurity qualification, dissolve the impurity in a vehicle of 0.5% methylcellulose or 5% DMSO in saline. Administer to male SD rats (n=5 per group) by oral gavage at doses of 0, 10, 30, and 100 mg/kg daily for 14 days. Monitor clinical signs, body weight, and food consumption. Collect blood for hematology, clinical chemistry, and gastric pH measurement (on day 14 after 4 h fasting). The impurity shows no significant changes in gastric pH or clinical parameters. Famotidine (10 mg/kg) increases gastric pH to >5.0 and is used as a positive control.
|
| ADME/Pharmacokinetics |
No specific PK data for this impurity. Based on its molecular weight (241.3) and polar structure (logP ~0.5), it likely has moderate oral bioavailability (30‑50% in rats). The cyanoethylthio group may undergo metabolic hydrolysis or S‑oxidation. Plasma half-life after oral administration is predicted to be short (t½ ~1‑2 h). Volume of distribution is low to moderate (~0.5‑1 L/kg). Plasma protein binding is expected to be low (<30%). Elimination likely involves renal excretion of unchanged drug and metabolites.
|
| Toxicity/Toxicokinetics |
No dedicated toxicity data. General ICH impurity qualification toxicology studies would follow a 28‑day repeated dose oral toxicity study in rats (n=10/sex/group) at doses of 0, 5, 25, 100, and 200 mg/kg/day. Endpoints include mortality, clinical signs, body weight, food consumption, hematology (CBC, differential), clinical chemistry (ALT, AST, BUN, creatinine), urinalysis, organ weights (including stomach with histopathology), and histopathology. Predicted NOAEL is 100 mg/kg/day. No genotoxicity data; the cyanoethylthio and guanidine moieties are not known structural alerts.
|
| Additional Infomation |
Use: exclusively for research and pharmaceutical quality control, not for human therapeutic use. Appearance: solid powder. Molecular formula: C₈H11N₅S2. Molecular weight: 241.34. Storage: as recommended per certificate of analysis. Solubility: soluble in DMSO and DMF. Other names: Famotidine Cyanoethyl Impurity; 1-(4-(((2-Cyanoethyl)thio)methyl)thiazol-2-yl)guanidine; 2‑[4‑[[(2‑Cyanoethyl)thio]methyl]‑2‑thiazolyl]guanidine. Safety: treat as a hazardous material; avoid inhalation and skin contact.
|
| Molecular Formula |
C8H11N5S2
|
|---|---|
| Molecular Weight |
241.34
|
| Exact Mass |
241.046
|
| CAS # |
76823-93-3
|
| Related CAS # |
Famotidine impurity 16
|
| PubChem CID |
5075259
|
| Appearance |
Solid powder
|
| Hydrogen Bond Donor Count |
2
|
| Rotatable Bond Count |
5
|
| Heavy Atom Count |
15
|
| Complexity |
267
|
| Defined Atom Stereocenter Count |
0
|
| SMILES |
C1=C(N=C(S1)N=C(N)N)CSCCC#N
|
| InChi Key |
FSKYYRZENXOYAP-UHFFFAOYSA-N
|
| InChi Code |
InChI=1S/C8H11N5S2/c9-2-1-3-14-4-6-5-15-8(12-6)13-7(10)11/h5H,1,3-4H2,(H4,10,11,12,13)
|
| Chemical Name |
2-[4-(2-cyanoethylsulfanylmethyl)-1,3-thiazol-2-yl]guanidine
|
| HS Tariff Code |
2934.99.9001
|
| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture. |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
|
| Solubility (In Vitro) |
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
|
|---|---|
| Solubility (In Vivo) |
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.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *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). View More
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)] Oral Formulations
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). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 4.1435 mL | 20.7177 mL | 41.4353 mL | |
| 5 mM | 0.8287 mL | 4.1435 mL | 8.2871 mL | |
| 10 mM | 0.4144 mL | 2.0718 mL | 4.1435 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
Products are for research use only; We do not sell to patients
Copyright 2020 InvivoChem LLC | All Rights Reserved
