OXi-4503 sodium

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MedKoo CAT#: 205570

CAS#: 288847-34-7 (sodium)

Description: OXi-4503 is the diphosphate prodrug of the stilbenoid combretastatin A1, originally isolated from the plant Combretum caffrum, with vascular-disrupting and antineoplastic activities. Upon administration, combretastatin A1 diphosphate (CA1P) is dephosphorylated to the active metabolite combretastatin A1 (CA1), which promotes rapid microtubule depolymerization; endothelial cell mitotic arrest and apoptosis, destruction of the tumor vasculature, disruption of tumor blood flow and tumor cell necrosis may ensue.

Chemical Structure

OXi-4503 sodium
CAS# 288847-34-7 (sodium)

Theoretical Analysis

MedKoo Cat#: 205570
Name: OXi-4503 sodium
CAS#: 288847-34-7 (sodium)
Chemical Formula: C18H18Na4O12P2
Exact Mass: 0.00
Molecular Weight: 580.230
Elemental Analysis: C, 37.26; H, 3.13; Na, 15.85; O, 33.09; P, 10.68

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.
Note: Price will be listed if it is available in the future.

Related CAS #: 288847-35-8 (free acid)   288847-34-7 (sodium)   1014615-46-3 (potassium)    

Synonym: OXi4503; OXi-4503; OXi 4503; OXi-4503 sodium, CA1P; Combretastatin A-1 phosphate.

IUPAC/Chemical Name: sodium (Z)-3-methoxy-6-(3,4,5-trimethoxystyryl)-1,2-phenylene bis(phosphate)


InChi Code: InChI=1S/C18H22O12P2.4Na/c1-25-13-8-7-12(16(29-31(19,20)21)18(13)30-32(22,23)24)6-5-11-9-14(26-2)17(28-4)15(10-11)27-3;;;;/h5-10H,1-4H3,(H2,19,20,21)(H2,22,23,24);;;;/q;4*+1/p-4/b6-5-;;;;

SMILES Code: COC1=C(OC)C(OC)=CC(/C=C\C2=C(OP([O-])([O-])=O)C(OP([O-])([O-])=O)=C(OC)C=C2)=C1.[Na+].[Na+].[Na+].[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, 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:
In vitro activity:
In vivo activity:

Preparing Stock Solutions

The following data is based on the product molecular weight 580.23 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:
In vivo protocol:

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1: Lee JA, Biel NM, Kozikowski RT, Siemann DW, Sorg BS. In vivo spectral and fluorescence microscopy comparison of microvascular function after treatment with OXi4503, Sunitinib and their combination in Caki-2 tumors. Biomed Opt Express. 2014 May 28;5(6):1965-79. doi: 10.1364/BOE.5.001965. eCollection 2014 Jun 1. PubMed PMID: 24940553; PubMed Central PMCID: PMC4052922.

2: Fifis T, Nguyen L, Malcontenti-Wilson C, Chan LS, Nunes Costa PL, Daruwalla J, Nikfarjam M, Muralidharan V, Waltham M, Thompson EW, Christophi C. Treatment with the vascular disruptive agent OXi4503 induces an immediate and widespread epithelial to mesenchymal transition in the surviving tumor. Cancer Med. 2013 Oct;2(5):595-610. doi: 10.1002/cam4.109. Epub 2013 Aug 18. PubMed PMID: 24403226; PubMed Central PMCID: PMC3892792.

3: Stratford MR, Folkes LK. Quantitative determination of the anticancer prodrug combretastatin A1 phosphate (OXi4503, CA1P), the active CA1 and its glucuronide metabolites in human urine and of CA1 in plasma by HPLC with mass spectrometric detection. J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jun 1;898:1-6. doi: 10.1016/j.jchromb.2012.03.040. Epub 2012 Apr 24. PubMed PMID: 22578514.

4: Cummings J, Zweifel M, Smith N, Ross P, Peters J, Rustin G, Price P, Middleton MR, Ward T, Dive C. Evaluation of cell death mechanisms induced by the vascular disrupting agent OXi4503 during a phase I clinical trial. Br J Cancer. 2012 May 22;106(11):1766-71. doi: 10.1038/bjc.2012.165. Epub 2012 Apr 26. PubMed PMID: 22538971; PubMed Central PMCID: PMC3364117.

5: Patterson DM, Zweifel M, Middleton MR, Price PM, Folkes LK, Stratford MR, Ross P, Halford S, Peters J, Balkissoon J, Chaplin DJ, Padhani AR, Rustin GJ. Phase I clinical and pharmacokinetic evaluation of the vascular-disrupting agent OXi4503 in patients with advanced solid tumors. Clin Cancer Res. 2012 Mar 1;18(5):1415-25. doi: 10.1158/1078-0432.CCR-11-2414. Epub 2012 Jan 10. PubMed PMID: 22235096.

6: Stratford MR, Folkes LK. Validation of a method for the determination of the anticancer agent Combretastatin A1 phosphate (CA1P, OXi4503) in human plasma by HPLC with post-column photolysis and fluorescence detection. J Chromatogr B Analyt Technol Biomed Life Sci. 2011 Sep 1;879(25):2673-6. doi: 10.1016/j.jchromb.2011.07.014. Epub 2011 Jul 18. PubMed PMID: 21820978.

7: Rice L, Pampo C, Lepler S, Rojiani AM, Siemann DW. Support of a free radical mechanism for enhanced antitumor efficacy of the microtubule disruptor OXi4503. Microvasc Res. 2011 Jan;81(1):44-51. doi: 10.1016/j.mvr.2010.10.003. Epub 2010 Oct 23. PubMed PMID: 20974154; PubMed Central PMCID: PMC3021177.

8: Wankhede M, Dedeugd C, Siemann DW, Sorg BS. In vivo functional differences in microvascular response of 4T1 and Caki-1 tumors after treatment with OXi4503. Oncol Rep. 2010 Mar;23(3):685-92. PubMed PMID: 20127007; PubMed Central PMCID: PMC2978044.

9: 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.

10: Chan LS, Malcontenti-Wilson C, Muralidharan V, Christophi C. Alterations in vascular architecture and permeability following OXi4503 treatment. Anticancer Drugs. 2008 Jan;19(1):17-22. PubMed PMID: 18043126.