WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 406257

CAS#: 1232410-49-9

Description: VE-821 is the first highly selective and potent ATR inhibitor. VE-821 inhibited radiation- and gemcitabine-induced phosphorylation of Chk1, confirming inhibition of ATR signaling. Consistently, VE-821 significantly enhanced the sensitivity of PSN-1, MiaPaCa-2 and primary PancM pancreatic cancer cells to radiation and gemcitabine under both normoxic and hypoxic conditions. ATR inhibition by VE-821 led to inhibition of radiation-induced G 2/M arrest in cancer cells.

Chemical Structure

CAS# 1232410-49-9

Theoretical Analysis

MedKoo Cat#: 406257
Name: VE-821
CAS#: 1232410-49-9
Chemical Formula: C18H16N4O3S
Exact Mass: 368.09
Molecular Weight: 368.410
Elemental Analysis: C, 58.68; H, 4.38; N, 15.21; O, 13.03; S, 8.70

Price and Availability

Size Price Availability Quantity
10mg USD 110 Ready to ship
25mg USD 200 Ready to ship
50mg USD 350 Ready to ship
100mg USD 600 Ready to ship
200mg USD 1050 Ready to ship
500mg USD 1850 Ready to ship
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Synonym: VE821; VE-821; VE 821.

IUPAC/Chemical Name: 3-amino-6-(4-(methylsulfonyl)phenyl)-N-phenylpyrazine-2-carboxamide


InChi Code: InChI=1S/C18H16N4O3S/c1-26(24,25)14-9-7-12(8-10-14)15-11-20-17(19)16(22-15)18(23)21-13-5-3-2-4-6-13/h2-11H,1H3,(H2,19,20)(H,21,23)

SMILES Code: O=C(C1=NC(C2=CC=C(S(=O)(C)=O)C=C2)=CN=C1N)NC3=CC=CC=C3

Appearance: White to beige solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO, not in water

Shelf Life: >5 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

More Info:         

Biological target: VE-821 is a potent ATP-competitive inhibitor of ATR with Ki/IC50 of 13 nM/26 nM.
In vitro activity: HeLa, U2OS, and 1BR-hTERT (normal) cells were pre-treated with 1 μM VE-821 for 1 hour and irradiated with either high LET carbon ions or X-rays. Cell survival, cell cycle distribution, cell growth, and micronuclei formation were evaluated. VE-821 caused abrogation of G2/M checkpoint and forced irradiated cells to divide into daughter cells. It was also found that carbon ions caused a higher number of multiple micronuclei than X-rays, leading to decreased cell survival in tumor cells when treated with VE-821, while the survival of irradiated normal cells were not significantly affected by this inhibitor. Reference: Radiat Oncol. 2015 Aug 19;10:175.
In vivo activity:

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
DMSO 50.0 135.72

Preparing Stock Solutions

The following data is based on the product molecular weight 368.41 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL
Formulation protocol:
In vitro protocol: 1. Fujisawa H, Nakajima NI, Sunada S, Lee Y, Hirakawa H, Yajima H, Fujimori A, Uesaka M, Okayasu R. VE-821, an ATR inhibitor, causes radiosensitization in human tumor cells irradiated with high LET radiation. Radiat Oncol. 2015 Aug 19;10:175. doi: 10.1186/s13014-015-0464-y. PMID: 26286029; PMCID: PMC4554350. 2. Prevo R, Fokas E, Reaper PM, Charlton PA, Pollard JR, McKenna WG, Muschel RJ, Brunner TB. The novel ATR inhibitor VE-821 increases sensitivity of pancreatic cancer cells to radiation and chemotherapy. Cancer Biol Ther. 2012 Sep;13(11):1072-81. doi: 10.4161/cbt.21093. Epub 2012 Jul 24. PMID: 22825331; PMCID: PMC3461814.
In vivo protocol:

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1: Huntoon CJ, Flatten KS, Wahner Hendrickson AE, Huehls AM, Sutor SL, Kaufmann SH, Karnitz LM. ATR inhibition broadly sensitizes ovarian cancer cells to chemotherapy independent of BRCA status. Cancer Res. 2013 Apr 2. [Epub ahead of print] PubMed PMID: 23548269.

2: Prevo R, Fokas E, Reaper PM, Charlton PA, Pollard JR, McKenna WG, Muschel RJ, Brunner TB. The novel ATR inhibitor VE-821 increases sensitivity of pancreatic cancer cells to radiation and chemotherapy. Cancer Biol Ther. 2012 Sep;13(11):1072-81. doi: 10.4161/cbt.21093. Epub 2012 Jul 24. PubMed PMID: 22825331; PubMed Central PMCID: PMC3461814.

3: Pires IM, Olcina MM, Anbalagan S, Pollard JR, Reaper PM, Charlton PA, McKenna WG, Hammond EM. Targeting radiation-resistant hypoxic tumour cells through ATR inhibition. Br J Cancer. 2012 Jul 10;107(2):291-9. doi: 10.1038/bjc.2012.265. Epub 2012 Jun 19. PubMed PMID: 22713662; PubMed Central PMCID: PMC3394988.

4: Reaper PM, Griffiths MR, Long JM, Charrier JD, Maccormick S, Charlton PA, Golec JM, Pollard JR. Selective killing of ATM- or p53-deficient cancer cells through inhibition of ATR. Nat Chem Biol. 2011 Apr 13;7(7):428-30. doi: 10.1038/nchembio.573. PubMed PMID: 21490603.