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

MedKoo CAT#: 540242

CAS#: 99570-78-2

Description: K252b is a staurosporine analog and PKC inhibitor that suppresses DNA synthesis. It also inhibits microbial ectoprotein kinases and inhibits IgE cross-linking-dependent degranulation in basophils.

Price and Availability




K252b is not in stock, may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to sales@medkoo.com to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 540242
Name: K252b
CAS#: 99570-78-2
Chemical Formula: C26H19N3O5
Exact Mass: 453.1325
Molecular Weight: 453.45
Elemental Analysis: C, 68.87; H, 4.22; N, 9.27; O, 17.64

Synonym: K252b; K 252 b; K-252-b

IUPAC/Chemical Name: 7-hydroxy-8-methyl-15-oxo-5,6,7,8,14,15-hexahydro-13H-16-oxa-4b,8a,14-triaza-5,8-methanodibenzo[b,h]cycloocta[jkl]cyclopenta[e]-as-indacene-7-carboxylic acid


InChi Code: InChI=1S/C26H19N3O5/c1-25-26(33,24(31)32)10-17(34-25)28-15-8-4-2-6-12(15)19-20-14(11-27-23(20)30)18-13-7-3-5-9-16(13)29(25)22(18)21(19)28/h2-9,17,33H,10-11H2,1H3,(H,27,30)(H,31,32)

SMILES Code: CC12C(C(O)=O)(O)CC(N3C4=CC=CC=C4C5=C6C(CNC6=O)=C7C8=CC=CC=C8N2C7=C53)O1

Technical Data

Solid powder

>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).

Soluble in DMSO

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).

Harmonized System Code:


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2: Ross AH, McKinnon CA, Daou MC, Ratliff K, Wolf DE. Differential biological effects of K252 kinase inhibitors are related to membrane solubility but not to permeability. J Neurochem. 1995 Dec;65(6):2748-56. PubMed PMID: 7595574.

3: Takeda M, Takahashi M, Hara N, Matsumoto S. Glial cell line-derived neurotrophic factor modulates the excitability of nociceptive trigeminal ganglion neurons via a paracrine mechanism following inflammation. Brain Behav Immun. 2013 Feb;28:100-7. doi: 10.1016/j.bbi.2012.10.023. Epub 2012 Nov 3. PubMed PMID: 23131757.

4: Bacot SM, Feldman GM, Yamada KM, Dhawan S. Pathogenic prion protein fragment (PrP106-126) promotes human immunodeficiency virus type-1 infection in peripheral blood monocyte-derived macrophages. Virology. 2015 Feb;476:372-6. doi: 10.1016/j.virol.2014.11.032. Epub 2015 Jan 9. PubMed PMID: 25589240; PubMed Central PMCID: PMC5282598.

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7: Kawamura N, Kawamura K, Manabe M, Tanaka T. Inhibition of brain-derived neurotrophic factor/tyrosine kinase B signaling suppresses choriocarcinoma cell growth. Endocrinology. 2010 Jul;151(7):3006-14. doi: 10.1210/en.2009-1378. Epub 2010 May 12. PubMed PMID: 20463055.

8: Gadbois DM, Crissman HA, Tobey RA, Bradbury EM. Multiple kinase arrest points in the G1 phase of nontransformed mammalian cells are absent in transformed cells. Proc Natl Acad Sci U S A. 1992 Sep 15;89(18):8626-30. PubMed PMID: 1528872; PubMed Central PMCID: PMC49973.

9: Takeda M, Kitagawa J, Nasu M, Takahashi M, Iwata K, Matsumoto S. Glial cell line-derived neurotrophic factor acutely modulates the excitability of rat small-diameter trigeminal ganglion neurons innervating facial skin. Brain Behav Immun. 2010 Jan;24(1):72-82. doi: 10.1016/j.bbi.2009.08.002. Epub 2009 Aug 11. PubMed PMID: 19679180.

10: Kawamura K, Kawamura N, Sato W, Fukuda J, Kumagai J, Tanaka T. Brain-derived neurotrophic factor promotes implantation and subsequent placental development by stimulating trophoblast cell growth and survival. Endocrinology. 2009 Aug;150(8):3774-82. doi: 10.1210/en.2009-0213. Epub 2009 Apr 16. PubMed PMID: 19372195.

11: Tsuji S, Yamashita T, Matsuda Y, Nagai Y. A novel glycosignaling system: GQ1b-dependent neuritogenesis of human neuroblastoma cell line, GOTO, is closely associated with GQ1b-dependent ecto-type protein phosphorylation. Neurochem Int. 1992 Dec;21(4):549-54. PubMed PMID: 1303737.

12: Martín ED, Buño W. Stabilizing effects of extracellular ATP on synaptic efficacy and plasticity in hippocampal pyramidal neurons. Eur J Neurosci. 2005 Feb;21(4):936-44. PubMed PMID: 15787700.

13: Lautrette C, Loum-Ribot E, Petit D, Vermot-Desroches C, Wijdenes J, Jauberteau MO. Increase of Fas-induced apoptosis by inhibition of extracellular phosphorylation of Fas receptor in Jurkat cell line. Apoptosis. 2006 Jul;11(7):1195-204. PubMed PMID: 16699962.

14: Kuroda Y, Ichikawa M, Muramoto K, Kobayashi K, Matsuda Y, Ogura A, Kudo Y. Block of synapse formation between cerebral cortical neurons by a protein kinase inhibitor. Neurosci Lett. 1992 Feb 3;135(2):255-8. PubMed PMID: 1625805.

15: Li Y, Calfa G, Inoue T, Amaral MD, Pozzo-Miller L. Activity-dependent release of endogenous BDNF from mossy fibers evokes a TRPC3 current and Ca2+ elevations in CA3 pyramidal neurons. J Neurophysiol. 2010 May;103(5):2846-56. doi: 10.1152/jn.01140.2009. Epub 2010 Mar 10. PubMed PMID: 20220070; PubMed Central PMCID: PMC2867575.

16: Thompson AF, Levin LA. Neuronal differentiation by analogs of staurosporine. Neurochem Int. 2010 Mar;56(4):554-60. doi: 10.1016/j.neuint.2009.12.018. Epub 2010 Jan 4. PubMed PMID: 20043966; PubMed Central PMCID: PMC2831141.

17: Pong K, Xu RY, Beck KD, Zhang TJ, Louis JC. Inhibition of glial cell line-derived neurotrophic factor induced intracellular activity by K-252b on dopaminergic neurons. J Neurochem. 1997 Sep;69(3):986-94. PubMed PMID: 9282920.

18: Nagashima K, Nakanishi S, Matsuda Y. Inhibition of nerve growth factor-induced neurite outgrowth of PC12 cells by a protein kinase inhibitor which does not permeate the cell membrane. FEBS Lett. 1991 Nov 18;293(1-2):119-23. PubMed PMID: 1959642.

19: Pollack S, Young L, Bilsland J, Wilkie N, Ellis S, Hefti F, Broughton H, Harper S. The staurosporine-like compound L-753,000 (NB-506) potentiates the neurotrophic effects of neurotrophin-3 by acting selectively at the TrkA receptor. Mol Pharmacol. 1999 Jul;56(1):185-95. PubMed PMID: 10385700.

20: Ikushima M, Ishii M, Ohishi M, Yamamoto K, Ogihara T, Rakugi H, Kurachi Y. ANG II inhibits insulin-mediated production of PI 3,4,5-trisphosphates via a Ca2+-dependent but PKC-independent pathway in the cardiomyocytes. Am J Physiol Heart Circ Physiol. 2010 Sep;299(3):H680-9. doi: 10.1152/ajpheart.00220.2009. Epub 2010 Jul 2. PubMed PMID: 20601457.