Fosbretabulin disodium

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MedKoo CAT#: 200800

CAS#: 168555-66-6 (disodium)

Description: Fosbretabulin disodium is the disodium salt of a water-soluble phosphate derivative of a natural stilbenoid phenol derived from the African bush willow (Combretum caffrum) with potential vascular disrupting and antineoplastic activities. Upon administration, the prodrug fosbretabulin is dephosphorylated to its active metabolite, the microtubule-depolymerizing agent combretastatin A4, which binds to tubulin dimers and prevents microtubule polymerization, resulting in mitotic arrest and apoptosis in endothelial cells. In addition, this agent disrupts the engagement of the endothelial cell–specific junctional molecule vascular endothelial-cadherin (VE-cadherin) and so the activity of the VE-cadherin/β-catenin/Akt signaling pathway, which may result in the inhibition of endothelial cell migration and capillary tube formation. As a result of fosbretabulin's dual mechanism of action, the tumor vasculature collapses, resulting in reduced tumor blood flow and ischemic necrosis of tumor tissue.

Chemical Structure

Fosbretabulin disodium
CAS# 168555-66-6 (disodium)

Theoretical Analysis

MedKoo Cat#: 200800
Name: Fosbretabulin disodium
CAS#: 168555-66-6 (disodium)
Chemical Formula: C18H19Na2O8P
Exact Mass:
Molecular Weight: 440.29
Elemental Analysis: C, 49.10; H, 4.35; Na, 10.44; O, 29.07; P, 7.03

Price and Availability

Size Price Availability Quantity
50.0mg USD 190.0 Same day
100.0mg USD 350.0 Same day
200.0mg USD 550.0 Same day
500.0mg USD 1150.0 Same day
1.0g USD 1850.0 Same day
2.0g USD 3250.0 Same day
5.0g USD 5450.0 Same day
10.0g USD 8950.0 2 Weeks
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Related CAS #: 168555-66-6 (disodium)   222030-63-9 (free acid)   404886-32-4 ( tromethamine)  

Synonym: Combretastatin A4 phosphate disodium; CA4P; CA4DP; Combretastatin A4 phosphate; Fosbretabulin disodium; Zybrestat

IUPAC/Chemical Name: Disodium [2-methoxy-5-[(Z)-2-(3,4,5-trimethoxyphenyl)ethenyl]phenyl] phosphate


InChi Code: InChI=1S/C18H21O8P.2Na/c1-22-14-8-7-12(9-15(14)26-27(19,20)21)5-6-13-10-16(23-2)18(25-4)17(11-13)24-3;;/h5-11H,1-4H3,(H2,19,20,21);;/q;2*+1/p-2/b6-5-;;

SMILES Code: O=P([O-])([O-])OC1=CC(/C=C\C2=CC(OC)=C(OC)C(OC)=C2)=CC=C1OC.[Na+].[Na+]

Appearance: white 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 440.29 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: Sosa JA, Balkissoon J, Lu SP, Langecker P, Elisei R, Jarzab B, Bal CS, Marur S, Gramza A, Ondrey F. Thyroidectomy followed by fosbretabulin (CA4P) combination regimen appears to suggest improvement in patient survival in anaplastic thyroid cancer. Surgery. 2012 Dec;152(6):1078-87. doi: 10.1016/j.surg.2012.08.036. Review. PubMed PMID: 23158178.

2: Venegas B, Zhu W, Haloupek NB, Lee J, Zellhart E, Sugár IP, Kiani MF, Chong PL. Cholesterol superlattice modulates CA4P release from liposomes and CA4P cytotoxicity on mammary cancer cells. Biophys J. 2012 May 2;102(9):2086-94. doi: 10.1016/j.bpj.2012.03.063. PubMed PMID: 22824272; PubMed Central PMCID: PMC3341537.

3: Nathan P, Zweifel M, Padhani AR, Koh DM, Ng M, Collins DJ, Harris A, Carden C, Smythe J, Fisher N, Taylor NJ, Stirling JJ, Lu SP, Leach MO, Rustin GJ, Judson I. Phase I trial of combretastatin A4 phosphate (CA4P) in combination with bevacizumab in patients with advanced cancer. Clin Cancer Res. 2012 Jun 15;18(12):3428-39. doi: 10.1158/1078-0432.CCR-11-3376. Epub 2012 May 29. PubMed PMID: 22645052.

4: Rustin GJ, Shreeves G, Nathan PD, Gaya A, Ganesan TS, Wang D, Boxall J, Poupard L, Chaplin DJ, Stratford MR, Balkissoon J, Zweifel M. A Phase Ib trial of CA4P (combretastatin A-4 phosphate), carboplatin, and paclitaxel in patients with advanced cancer. Br J Cancer. 2010 Apr 27;102(9):1355-60. doi: 10.1038/sj.bjc.6605650. Epub 2010 Apr 13. PubMed PMID: 20389300; PubMed Central PMCID: PMC2865759.

5: Siemann DW, Chaplin DJ, Walicke PA. A review and update of the current status of the vasculature-disabling agent combretastatin-A4 phosphate (CA4P). Expert Opin Investig Drugs. 2009 Feb;18(2):189-97. doi: 10.1517/13543780802691068 . Review. PubMed PMID: 19236265; PubMed Central PMCID: PMC3593193.

6: Siemann DW, Shi W. Dual targeting of tumor vasculature: combining Avastin and vascular disrupting agents (CA4P or OXi4503). Anticancer Res. 2008 Jul-Aug;28(4B):2027-31. PubMed PMID: 18751370; PubMed Central PMCID: PMC2788501.

7: Petit I, Karajannis MA, Vincent L, Young L, Butler J, Hooper AT, Shido K, Steller H, Chaplin DJ, Feldman E, Rafii S. The microtubule-targeting agent CA4P regresses leukemic xenografts by disrupting interaction with vascular cells and mitochondrial-dependent cell death. Blood. 2008 Feb 15;111(4):1951-61. Epub 2007 Nov 16. PubMed PMID: 18024794; PubMed Central PMCID: PMC2234044.

8: Salmon BA, Salmon HW, Siemann DW. Monitoring the treatment efficacy of the vascular disrupting agent CA4P. Eur J Cancer. 2007 Jul;43(10):1622-9. Epub 2007 Apr 23. PubMed PMID: 17451938; PubMed Central PMCID: PMC2962830.

9: Salmon HW, Mladinich C, Siemann DW. Evaluations of vascular disrupting agents CA4P and OXi4503 in renal cell carcinoma (Caki-1) using a silicon based microvascular casting technique. Eur J Cancer. 2006 Nov;42(17):3073-8. Epub 2006 Sep 7. PubMed PMID: 16956760.

Additional Information

Related CAS#

168555-66-6 (fosbretabulin disodium);
222030-63-9 (fosbretabulin);
82855-09-2 (combretastatin);
117048 -59-6 (combretastatin A4)