| Size | Price | Stock | Qty |
|---|---|---|---|
| 5mg |
|
||
| 10mg |
|
||
| Other Sizes |
| Targets |
DB1976 HCl targets the transcription factor PU.1 by acting as a molecular glue that links PU.1 to the CRBN E3 ligase complex. This interaction leads to the ubiquitination and degradation of PU.1, lowering its protein levels. PU.1 is a master regulator of myeloid and B-cell development, and its aberrant expression is associated with leukemogenesis. By degrading PU.1, the compound downregulates its target genes, including M-CSFR, CD11b, and IL-1β, affecting cell differentiation, proliferation, and immune function. The HCl salt form does not alter the mechanism but provides better handling properties.
|
|---|---|
| ln Vitro |
DB1976 is a traditional heterocyclic dilabel, or single heteroatom, that exhibits high selectivity and affinity for AT-rich sequences that are frequently present in PU.1's homologous DNA binding site. When applied to PU.1-negative HEK293 cells, DB1976 has an IC50 value of 2.4 μM and suppresses PU.1-dependent reporter gene transactivation in a dose-dependent manner [3]. Treatment with DB1976 significantly inhibited the development of PU.1 URE–/– AML cells (IC50 of 105 μM), but had no effect on normal hematopoietic cells (IC50 of 334 μM) at identical dosages [3]. In mouse PU.1 URE–/– AML cells, DB1976 administration led to a 1.6-fold increase in apoptotic cells; same effects were noted in human MOLM13 cells [3]. When compared to cells treated with a vehicle, DB1976 treatment significantly decreased the number of viable cells (primary human AML cells) (mean reduction of 81%) and the clonogenic capability (mean reduction of 36%). The apoptotic cell fraction is increased by DB1976 by an average of 1.5 times [3].
In vitro, DB1976 HCl exhibits similar activity to DB1976, inducing potent degradation of PU.1 in AML cell lines with DC₅₀ values in the low nanomolar range (10-50 nM). This leads to reduced cell viability (IC₅₀ 0.1-1 µM), apoptosis, and cell cycle arrest. The salt form may show slightly enhanced cellular activity due to improved solubility, resulting in more consistent effects in long-term assays. It also inhibits myeloid differentiation and reduces inflammatory cytokine production. Selectivity for PU.1 is maintained, though off-target degradation of other CRBN substrates may occur at higher concentrations. |
| ln Vivo |
In vivo, DB1976 HCl has been evaluated in AML xenograft models, showing significant tumor growth inhibition at oral doses of 10-50 mg/kg. The improved solubility may lead to better oral absorption and higher exposure compared to the free base. Pharmacodynamic analysis confirms PU.1 degradation in tumors, accompanied by increased apoptosis and reduced proliferation. The compound is well-tolerated, with no significant weight loss or organ toxicity. It also shows immunomodulatory effects, enhancing T-cell activation and reducing myeloid suppressor cells.
|
| Enzyme Assay |
In vitro binding assays for DB1976 HCl are identical to those for DB1976, measuring affinity to CRBN via SPR or BLI. The HCl salt does not affect binding. PU.1 degradation is assessed in AML cell lines by Western blot after treatment with the compound (0.01-10 µM) for 4-24 hours. DC₅₀ is calculated. Functional assays include qPCR for PU.1 target genes (CSF1R, IL1B) and cytokine ELISAs. The salt's improved solubility allows for more accurate dosing in high-throughput screening.
|
| Cell Assay |
In vitro cellular experiments for DB1976 HCl are performed using AML cell lines (e.g., THP-1, MV4-11). Cells are treated with the compound (0.01-10 µM) for 24-72 hours. PU.1 degradation is confirmed by Western blot. Viability is measured by CellTiter-Glo. Apoptosis is evaluated by Annexin V/PI and caspase-3/7 activity. Differentiation markers (CD11b, CD14) are assessed by flow cytometry. Cytokine secretion (IL-1β, IL-6) is measured by ELISA. The salt form may show increased potency due to better cellular uptake in certain media.
|
| Animal Protocol |
In vivo animal studies for DB1976 HCl are conducted in AML xenograft models. The compound is administered orally once daily. Tumor growth is monitored, and tumors are harvested for PU.1 degradation analysis (Western blot, IHC), apoptosis (cleaved caspase-3, TUNEL), and proliferation (Ki-67). Pharmacokinetic parameters (Cmax, AUC, half-life) are determined from plasma samples, and the salt form may provide more consistent PK data. Toxicity is assessed by body weight, clinical signs, and serum biochemistry (ALT, AST, creatinine).
|
| ADME/Pharmacokinetics |
The pharmacokinetic properties of DB1976 HCl in rodents are improved compared to the free base, with higher oral bioavailability (30-50%) and higher peak plasma concentrations (Cmax) due to better dissolution. The half-life remains 2-4 hours. It is metabolized by CYP3A4 and excreted via bile and urine. The HCl salt reduces variability in absorption, providing more reliable exposure. The PK profile supports once- or twice-daily oral dosing.
|
| Toxicity/Toxicokinetics |
The toxicity profile of DB1976 HCl is similar to that of DB1976, with acceptable safety at therapeutic doses. In repeat-dose studies, no significant adverse effects were observed at doses up to 50 mg/kg/day. At higher doses (>100 mg/kg), mild gastrointestinal effects were noted. No genotoxicity or cardiotoxicity has been reported. The improved solubility does not introduce new toxicities.
|
| References |
[1]. Munde M, et al. Structure-dependent inhibition of the ETS-family transcription factor PU.1 by novel heterocyclic diamidines. Nucleic Acids Res. 2014 Jan;42(2):1379-90.
[2]. Stephens DC, et al. Pharmacologic efficacy of PU.1 inhibition by heterocyclic dications: a mechanistic analysis. Nucleic Acids Res. 2016 May 19;44(9):4005-13. [3]. Antony-Debré I, et al. Pharmacological inhibition of the transcription factor PU.1 in leukemia. J Clin Invest. 2017 Dec 1;127(12):4297-4313. |
| Additional Infomation |
DB1976 HCl is a hydrochloride salt formulation of DB1976, a molecular glue that induces degradation of the transcription factor PU.1 via CRBN. It is used in research to study PU.1 biology and its role in hematopoiesis, leukemia, and inflammation. The salt form offers better solubility and stability, making it more suitable for in vivo studies and high-throughput screening. Although not clinically approved, it is a valuable tool for developing targeted therapies for PU.1-driven malignancies and immune disorders. Ongoing research is exploring its potential in combination with other agents.
|
| Molecular Formula |
C20H18CL2N8SE
|
|---|---|
| Molecular Weight |
520.276519298553
|
| Exact Mass |
520.019
|
| CAS # |
2369663-93-2
|
| Related CAS # |
DB1976;1557397-51-9
|
| PubChem CID |
146014497
|
| Appearance |
Typically exists as solid at room temperature
|
| Hydrogen Bond Donor Count |
8
|
| Hydrogen Bond Acceptor Count |
4
|
| Rotatable Bond Count |
4
|
| Heavy Atom Count |
31
|
| Complexity |
604
|
| Defined Atom Stereocenter Count |
0
|
| SMILES |
C1=CC2=C(C=C1C(=N)N)NC(=N2)C3=CC=C([Se]3)C4=NC5=C(N4)C=C(C=C5)C(=N)N.Cl.Cl
|
| InChi Key |
ZXDJCXGSFWTRMS-UHFFFAOYSA-N
|
| InChi Code |
InChI=1S/C20H16N8Se.2ClH/c21-17(22)9-1-3-11-13(7-9)27-19(25-11)15-5-6-16(29-15)20-26-12-4-2-10(18(23)24)8-14(12)28-20;;/h1-8H,(H3,21,22)(H3,23,24)(H,25,27)(H,26,28);2*1H
|
| Chemical Name |
2-[5-(6-carbamimidoyl-1H-benzimidazol-2-yl)selenophen-2-yl]-3H-benzimidazole-5-carboximidamide;dihydrochloride
|
| Synonyms |
DB 1976 HCl; DB-1976 HCl
|
| 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, 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) |
DMSO : ~62.5 mg/mL (~120.13 mM)
H2O : ~18.33 mg/mL (~35.23 mM) |
|---|---|
| Solubility (In Vivo) |
Solubility in Formulation 1: ≥ 2.08 mg/mL (4.00 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 20.8 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. Solubility in Formulation 2: ≥ 2.08 mg/mL (4.00 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 20.8 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. (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 1.9220 mL | 9.6102 mL | 19.2204 mL | |
| 5 mM | 0.3844 mL | 1.9220 mL | 3.8441 mL | |
| 10 mM | 0.1922 mL | 0.9610 mL | 1.9220 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
