≥98% (HPLC)

3-Amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide, 3-Amino-6-[4-(methylsulfonyl)phenyl]-N-phenyl-2-pyrazinecarboxamide, VE821
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
PubChem Substance ID:

Quality Level


≥98% (HPLC)




white to beige


DMSO: 10 mg/mL, clear
H2O: 10 mg/mL, clear

storage temp.


SMILES string




InChI key



VE-821 has been used as an inhibitor of ATM- and Rad3-related (ATR) protein in human cancer cells.


5, 25 mg in glass bottle

Biochem/physiol Actions

VE-821 is a potent ATP-competitive inhibitor of the DNA damage response (DDR) kinase Ataxia telangiectasia-mutated (ATM) and ATM- and Rad3-related (ATR) with a Ki of 13 nM. VE-821 has minimal cross-reactivity against the related PIKKs ATM, DNA-dependent protein kinase (DNA-PK), mTOR and PI3-kinase-γ (Ki of 16 μM, 2.2 μM, >1 μM and 3.9 μM, respectively) and against a large panel of unrelated protein kinases. VE-821 used alone caused death in a large fraction of cancer cell populations and also showed strong synergy with genotoxic agents. VE-821 increased sensitivity of cells to radiation and also sensitized cancer cells to a variety of chemotherapeutic agents.

Other Notes

VE-821 has been expertly reviewed and recommended by the Chemical Probes Portal. For more information, please visit the VE-821 probe summary on the Chemical Probes Portal website.


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

Human cancer cells utilize mitotic DNA synthesis to resist replication stress at telomeres regardless of their telomere maintenance mechanism
Ozgun Ozer, et al.
Oncotarget null
Tingting Li et al.
Aging, 12(14), 14791-14807 (2020-07-21)
Protection of telomere 1 (POT1), the telomeric single-stranded DNA (ssDNA)-binding protein in the shelterin complex, has been implicated in the DNA damage response, tumorigenesis and aging. Telomere dysfunction induced by telomere deprotection could accelerate cellular senescence in primary human cells....
Anastazja Poczta et al.
Scientific reports, 9(1), 14135-14135 (2019-10-03)
The present study investigated the effect of cladribine (CLA) and six of its derivatives containing a formamidine group at position 6 (CLA-FDM, CLA-FPAZ, CLA-FPIR, CLA-FPIP, CLA-FHEX, and CLA-FMOR) on acute promyelocytic, lymphoblastic, and acute monocytic leukemia cells. The role of...
Dorthe Aasland et al.
Cancer research, 79(1), 99-113 (2018-10-27)
The DNA-methylating drug temozolomide, which induces cell death through apoptosis, is used for the treatment of malignant glioma. Here, we investigate the mechanisms underlying the ability of temozolomide to induce senescence in glioblastoma cells. Temozolomide-induced senescence was triggered by the...
Anna K Simon et al.
Life science alliance, 3(3) (2020-02-20)
The iron-sulfur (FeS) cluster helicase DDX11 is associated with a human disorder termed Warsaw Breakage Syndrome. Interestingly, one disease-associated mutation affects the highly conserved arginine-263 in the FeS cluster-binding motif. Here, we demonstrate that the FeS cluster in DDX11 is...

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