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

MedKoo CAT#: 561414

CAS#: 51828-97-8

Description: MTOB is the substrate for the C-terminal Binding Protein (CtBP). MTOB can interfere with CtBP oncogenic activity in cell culture and in mice. It also positively regulates TCF-4 signaling, leading to cancer stem cells (CSC) growth and self-renewal.

Chemical Structure

CAS# 51828-97-8

Theoretical Analysis

MedKoo Cat#: 561414
Name: MTOB
CAS#: 51828-97-8
Chemical Formula: C5H7NaO3S
Exact Mass:
Molecular Weight: 170.16
Elemental Analysis: C, 35.29; H, 4.15; Na, 13.51; O, 28.21; S, 18.84

Price and Availability

Size Price Availability Quantity
10.0mg USD 170.0 2 Weeks
100.0mg USD 350.0 2 Weeks
200.0mg USD 650.0 2 Weeks
500.0mg USD 1450.0 2 Weeks
1.0g USD 2450.0 2 Weeks
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Synonym: MTOB; 4-methylthio 2-oxobutyric acid; KMBA; MTOB salt;

IUPAC/Chemical Name: 4-Methylsulfanyl-2-oxobutanoic acid sodium salt


InChi Code: InChI=1S/C5H8O3S.Na/c1-9-3-2-4(6)5(7)8;/h2-3H2,1H3,(H,7,8);/q;+1/p-1

SMILES Code: O=C([O-])C(CCSC)=O.[Na+]

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

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 170.16 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: Dcona MM, Morris BL, Ellis KC, Grossman SR. CtBP- an emerging oncogene and novel small molecule drug target: Advances in the understanding of its oncogenic action and identification of therapeutic inhibitors. Cancer Biol Ther. 2017 Jun 3;18(6):379-391. doi: 10.1080/15384047.2017.1323586. Epub 2017 May 22. PubMed PMID: 28532298; PubMed Central PMCID: PMC5536941.

2: Li M, Riddle S, Zhang H, D'Alessandro A, Flockton A, Serkova NJ, Hansen KC, Moldvan R, McKeon BA, Frid M, Kumar S, Li H, Liu H, Caánovas A, Medrano JF, Thomas MG, Iloska D, Plecitá-Hlavatá L, Ježek P, Pullamsetti S, Fini MA, El Kasmi KC, Zhang Q, Stenmark KR. Metabolic Reprogramming Regulates the Proliferative and Inflammatory Phenotype of Adventitial Fibroblasts in Pulmonary Hypertension Through the Transcriptional Corepressor C-Terminal Binding Protein-1. Circulation. 2016 Oct 11;134(15):1105-1121. Epub 2016 Aug 25. PubMed PMID: 27562971; PubMed Central PMCID: PMC5069179.

3: Korwar S, Morris BL, Parikh HI, Coover RA, Doughty TW, Love IM, Hilbert BJ, Royer WE Jr, Kellogg GE, Grossman SR, Ellis KC. Design, synthesis, and biological evaluation of substrate-competitive inhibitors of C-terminal Binding Protein (CtBP). Bioorg Med Chem. 2016 Jun 15;24(12):2707-15. doi: 10.1016/j.bmc.2016.04.037. Epub 2016 Apr 20. PubMed PMID: 27156192; PubMed Central PMCID: PMC4993153.

4: Hilbert BJ, Morris BL, Ellis KC, Paulsen JL, Schiffer CA, Grossman SR, Royer WE Jr. Structure-guided design of a high affinity inhibitor to human CtBP. ACS Chem Biol. 2015 Apr 17;10(4):1118-27. doi: 10.1021/cb500820b. Epub 2015 Jan 30. PubMed PMID: 25636004; PubMed Central PMCID: PMC4844192.

5: Patel J, Baranwal S, Love IM, Patel NJ, Grossman SR, Patel BB. Inhibition of C-terminal binding protein attenuates transcription factor 4 signaling to selectively target colon cancer stem cells. Cell Cycle. 2014;13(22):3506-18. doi: 10.4161/15384101.2014.958407. PubMed PMID: 25483087; PubMed Central PMCID: PMC4613182.

6: Hilbert BJ, Grossman SR, Schiffer CA, Royer WE Jr. Crystal structures of human CtBP in complex with substrate MTOB reveal active site features useful for inhibitor design. FEBS Lett. 2014 May 2;588(9):1743-8. doi: 10.1016/j.febslet.2014.03.026. Epub 2014 Mar 19. PubMed PMID: 24657618; PubMed Central PMCID: PMC4072453.

7: Stankiewicz TR, Schroeder EK, Kelsey NA, Bouchard RJ, Linseman DA. C-terminal binding proteins are essential pro-survival factors that undergo caspase-dependent downregulation during neuronal apoptosis. Mol Cell Neurosci. 2013 Sep;56:322-332. doi: 10.1016/j.mcn.2013.07.004. Epub 2013 Jul 13. PubMed PMID: 23859824; PubMed Central PMCID: PMC3791214.

8: May T, Yang J, Shoni M, Liu S, He H, Gali R, Ng SK, Crum C, Berkowitz RS, Ng SW. BRCA1 expression is epigenetically repressed in sporadic ovarian cancer cells by overexpression of C-terminal binding protein 2. Neoplasia. 2013 Jun;15(6):600-8. PubMed PMID: 23730208; PubMed Central PMCID: PMC3664992.

9: Mary C, Duek P, Salleron L, Tienz P, Bumann D, Bairoch A, Lane L. Functional identification of APIP as human mtnB, a key enzyme in the methionine salvage pathway. PLoS One. 2012;7(12):e52877. doi: 10.1371/journal.pone.0052877. Epub 2012 Dec 28. PubMed PMID: 23285211; PubMed Central PMCID: PMC3532061.

10: Liu J, Wang Z, Belchik SM, Edwards MJ, Liu C, Kennedy DW, Merkley ED, Lipton MS, Butt JN, Richardson DJ, Zachara JM, Fredrickson JK, Rosso KM, Shi L. Identification and Characterization of MtoA: A Decaheme c-Type Cytochrome of the Neutrophilic Fe(II)-Oxidizing Bacterium Sideroxydans lithotrophicus ES-1. Front Microbiol. 2012 Feb 8;3:37. doi: 10.3389/fmicb.2012.00037. eCollection 2012. PubMed PMID: 22347878; PubMed Central PMCID: PMC3274759.

11: Straza MW, Paliwal S, Kovi RC, Rajeshkumar B, Trenh P, Parker D, Whalen GF, Lyle S, Schiffer CA, Grossman SR. Therapeutic targeting of C-terminal binding protein in human cancer. Cell Cycle. 2010 Sep 15;9(18):3740-50. doi: 10.4161/cc.9.18.12936. Epub 2010 Sep 8. PubMed PMID: 20930544; PubMed Central PMCID: PMC3047800.

12: Quash G, Fournet G. Methionine-derived metabolites in apoptosis: therapeutic opportunities for inhibitors of their metabolism in chemoresistant cancer cells. Curr Med Chem. 2009;16(28):3686-700. PubMed PMID: 19747146.

13: García-García M, Martínez-Martínez I, Sánchez-Ferrer A, García-Carmona F. Production of the apoptotic cellular mediator 4-Methylthio-2-oxobutyric acid by using an enzymatic stirred tank reactor with in situ product removal. Biotechnol Prog. 2008 Jan-Feb;24(1):187-91. Epub 2007 Dec 20. PubMed PMID: 18092800.

14: Tang B, Kadariya Y, Murphy ME, Kruger WD. The methionine salvage pathway compound 4-methylthio-2-oxobutanate causes apoptosis independent of down-regulation of ornithine decarboxylase. Biochem Pharmacol. 2006 Sep 28;72(7):806-15. Epub 2006 Jul 25. PubMed PMID: 16870157.

15: Toba M, Kumita S, Cho K, Ibuki C, Kumazaki T, Takano T. Usefulness of gated myocardial perfusion SPECT imaging soon after exercise to identify postexercise stunning in patients with single-vessel coronary artery disease. J Nucl Cardiol. 2004 Nov-Dec;11(6):697-703. PubMed PMID: 15592193.

16: Quash G, Roch AM, Charlot C, Chantepie J, Thomas V, Hamedi-Sangsari F, Vila J. 4-methylthio 2-oxobutanoate transaminase: a specific target for antiproliferative agents. Bull Cancer. 2004 Apr;91(4):E61-79. PubMed PMID: 15562560.

17: Quash G, Fournet G, Reichert U. Anaplerotic reactions in tumour proliferation and apoptosis. Biochem Pharmacol. 2003 Aug 1;66(3):365-70. Review. PubMed PMID: 12907234.

18: Purchas RW, Fisher AV, Price MA, Berg RT. Relationships between beef carcass shape and muscle to bone ratio. Meat Sci. 2002 Jul;61(3):329-37. PubMed PMID: 22060858.

19: Toba M, Kumita S, Cho K, Mizumura S, Kijima T, Nakajo H, Kumazaki T. Comparison of Emory and Cedars-Sinai methods for assessment of left ventricular function from gated myocardial perfusion SPECT in patients with a small heart. Ann Nucl Med. 2000 Dec;14(6):421-6. PubMed PMID: 11210094.

20: Toba M, Ishida Y, Jukuchi K, Noguchi T, Itoh A, Nonogi H, Takamiya M. Use of ECG-gated SPET to assess the evolution of perfusion after acute myocardial infarction. Eur J Nucl Med. 2000 May;27(5):517-23. PubMed PMID: 10853806.


10.0mg / USD 170.0