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

MedKoo CAT#: 201330

CAS#: 180300-43-0

Description: Ethynylcytidine is a synthetic cytidine nucleoside containing a covalently bound ethynyl group with potential antineoplastic and radiosensitizing activities. 3'-C-ethynylcytidine is metabolized in tumor cells to ethynylcytidine triphosphate (ECTP), which inhibits RNA synthesis by competitive inhibition of RNA polymerases I, II and III; subsequently, RNase L is activated, resulting in apoptosis. RNase L is a potent antiviral and antiproliferative endoribonuclease that cleaves singled stranded RNA, causes 28s rRNA fragmentation, and activates Janus Kinase (JAK), a mitochondrial-dependent apoptosis signaling molecule. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus).

Chemical Structure

CAS# 180300-43-0

Theoretical Analysis

MedKoo Cat#: 201330
Name: Ethynylcytidine
CAS#: 180300-43-0
Chemical Formula: C11H13N3O5
Exact Mass: 267.08552
Molecular Weight: 267.23802
Elemental Analysis: C, 49.44; H, 4.90; N, 15.72; O, 29.93

Price and Availability

Size Price Availability Quantity
1.0mg USD 215.0 2 Weeks
5.0mg USD 415.0 2 Weeks
10.0mg USD 660.0 2 Weeks
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Synonym: ECydTAS106TAS 1063CEthynylcytidineAIDS241582AIDS241582; SB596168 3Ethynylcytidine.

IUPAC/Chemical Name: 1-(3-C-Ethynyl-beta-D-ribo-pentofuranosyl)cytosine


InChi Code: InChI=1S/C11H13N3O5/c1-2-11(18)6(5-15)19-9(8(11)16)14-4-3-7(12)13-10(14)17/h1,3-4,6,8-9,15-16,18H,5H2,(H2,12,13,17)/t6-,8+,9-,11-/m1/s1

SMILES Code: O=C1N([C@H]2[C@@H]([C@]([C@@H](CO)O2)(C#C)O)O)C=CC(N)=N1

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

Preparing Stock Solutions

The following data is based on the product molecular weight 267.23802 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: Schott S, Wallwiener M, Kootz B, Seeger H, Fehm T, Neubauer H. ATP chemosensitivity testing of new antitumor duplex drugs linking 3;-C-ethynylycytidine (ECyd) and 2 -deoxy-5-fluorouridine (5-FdU) in comparison to standard cytostatica and combinations thereof. Invest New Drugs. 2009 Dec 9. [Epub ahead of print] PubMed PMID: 19997962.

2: Bijnsdorp IV, Schwendener RA, Schott H, Fichtner I, Smid K, Laan AC, Schott S, Losekoot N, Honeywell RJ, Peters GJ. Cellular pharmacology of multi- and duplex drugsconsisting of ethynylcytidine and 5-fluoro-2'-deoxyuridine. Invest New Drugs. 2009 Dec 3. [Epub ahead of print] PubMed PMID: 19957099.

3: Wataya Y, Naito T, Sato A, Hiramoto A, Kitade Y, Sasaki T, Matsuda A, Fukushima M, Kim HS. Molecular mechanisms of apoptosis induced by 3'-ethynylcytidine. Nucleic Acids Symp Ser (Oxf). 2009;(53):291-2. PubMed PMID: 19749375.

4: Schott H, Schott S, Schwendener RA. Synthesis and in vitro activities of new anticancer duplex drugs linking 2'-deoxy-5-fluorouridine (5-FdU) with 3'-C-ethynylcytidine (ECyd) via a phosphodiester bonding. Bioorg Med Chem. 2009 Oct 1;17(19):6824-31. Epub 2009 Aug 21. PubMed PMID: 19744858.

5: Takada A, Kamiya H, Shuto S, Matsuda A, Harashima H. PK-PD modeling of 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine and the enhanced antitumor effect of its phospholipid derivatives in long-circulating liposomes. Int J Pharm. 2009 Jul 30;377(1-2):52-9. Epub 2009 May 6. PubMed PMID: 19426792.

6: Bijnsdorp IV, Schwendener RA, Schott H, Schott S, Fichtner I, Honeywell RJ, Losekoot N, Laan AC, Peters GJ. In vitro activity and mechanism of action of a duplex and multidrug of ethynylcytidine and 5-fluorodeoxyuridine. Nucleic Acids Symp Ser (Oxf). 2008;(52):651. PubMed PMID: 18776548.

7: Galmarini CM, Popowycz F, Joseph B. Cytotoxic nucleoside analogues: different strategies to improve their clinical efficacy. Curr Med Chem. 2008;15(11):1072-82. Review. PubMed PMID: 18473803.

8: Bayés M, Rabasseda X. Gateways to clinical trials. Methods Find Exp Clin Pharmacol. 2008 Jan-Feb;30(1):67-99. PubMed PMID: 18389098.

9: Naito T, Yokogawa T, Kim HS, Matsuda A, Sasaki T, Fukushima M, Kitade Y, Wataya Y. A novel apoptotic pathway of 3'-Ethynylcytidine(ECyd) involving the inhibition of RNA synthesis--the possibility of RNase L activated pathway as a target of ECyd. Nucleic Acids Symp Ser (Oxf). 2007;(51):435-6. PubMed PMID: 18029773.

10: Kazuno H, Shimamoto Y, Tsujimoto H, Fukushima M, Matsuda A, Sasaki T. Mechanism of action of a new antitumor ribonucleoside, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine (ECyd, TAS-106), differs from that of 5-fluorouracil. Oncol Rep. 2007 Jun;17(6):1453-60. PubMed PMID: 17487404.

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