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MedKoo CAT#: 200712

CAS#: 856691-93-5 (free base)

Description: CEP-11981, also known as ESK981, is an orally bioavailable inhibitor of vascular endothelial growth factor receptor (VEGFR) and Tie2 receptor tyrosine kinases with potential antiangiogenic and antineoplastic activities. Pan-VEGFR/Tie2 tyrosine kinase inhibitor CEP-11981 selectively binds to VEGFR and Tie2 receptor tyrosine kinases, which may result the inhibition of endothelial cell migration, proliferation and survival and the inhibition of tumor cell proliferation and tumor cell death.

Chemical Structure

CAS# 856691-93-5 (free base)

Theoretical Analysis

MedKoo Cat#: 200712
Name: CEP-11981
CAS#: 856691-93-5 (free base)
Chemical Formula: C28H27N7O
Exact Mass: 477.22771
Molecular Weight: 477.56
Elemental Analysis: C, 70.42; H, 5.70; N, 20.53; O, 3.35

Price and Availability

This product is not in stock, which may be available by custom synthesis. For cost-effective reason, minimum order is 1g (price is usually high, lead time is 2~3 months, depending on the technical challenge). Quote less than 1g will not be provided. To request quote, please email to sales @medkoo.com or click below button.
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Related CAS #: 901128-79-8 (tosylate)   856691-93-5 (free base)  

Synonym: CEP11981; CEP 11981; CEP11981; BOL303213X; BOL-303213X; BOL 303213X; ESK981; ESK-981; ESK 981;

IUPAC/Chemical Name: 13-isobutyl-4-methyl-10-(pyrimidin-2-ylamino)-4,7,8,13-tetrahydro-1H-indazolo[5,4-a]pyrrolo[3,4-c]carbazol-6(2H)-one


InChi Code: InChI=1S/C28H27N7O/c1-15(2)13-35-22-8-5-16(32-28-29-9-4-10-30-28)11-18(22)24-19-12-31-27(36)25(19)23-17(26(24)35)6-7-21-20(23)14-34(3)33-21/h4-5,8-11,14-15H,6-7,12-13H2,1-3H3,(H,31,36)(H,29,30,32)


Appearance: 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: >2 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

Preparing Stock Solutions

The following data is based on the product molecular weight 477.56 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

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1: Pili R, Carducci M, Brown P, Hurwitz H. An open-label study to determine the maximum tolerated dose of the multitargeted tyrosine kinase inhibitor CEP-11981 in patients with advanced cancer. Invest New Drugs. 2014 Dec;32(6):1258-68. doi: 10.1007/s10637-014-0147-9. Epub 2014 Aug 26. PMID: 25152243; PMCID: PMC4226840.

2: Jian W, Levitt JM, Lerner SP, Sonpavde G. The angiopoietin-TIE2 pathway is a potential therapeutic target in urothelial carcinoma. Anticancer Res. 2014 Jul;34(7):3377-82. PMID: 24982343.

3: Eroglu Z, Stein CA, Pal SK. Targeting angiopoietin-2 signaling in cancer therapy. Expert Opin Investig Drugs. 2013 Jul;22(7):813-25. doi: 10.1517/13543784.2013.793306. Epub 2013 Apr 27. PMID: 23621441.

4: Hudkins RL, Becknell NC, Zulli AL, Underiner TL, Angeles TS, Aimone LD, Albom MS, Chang H, Miknyoczki SJ, Hunter K, Jones-Bolin S, Zhao H, Bacon ER, Mallamo JP, Ator MA, Ruggeri BA. Synthesis and biological profile of the pan-vascular endothelial growth factor receptor/tyrosine kinase with immunoglobulin and epidermal growth factor-like homology domains 2 (VEGF-R/TIE-2) inhibitor 11-(2-m ethylpropyl)-12,13-dihydro-2-methyl-8-(pyrimidin-2-ylamino)-4H-indazolo[5,4-a]py rrolo[3,4-c]carbazol-4-one (CEP-11981): a novel oncology therapeutic agent. J Med Chem. 2012 Jan 26;55(2):903-13. doi: 10.1021/jm201449n. Epub 2012 Jan 6. Erratum in: J Med Chem. 2012 Apr 26;55(8):4025. PMID: 22148921.

Additional Information