Physicochemical Properties
Molecular Formula | C12H15FN5O12P3 |
Molecular Weight | 533.193488359451 |
Exact Mass | 532.99 |
CAS # | 950913-56-1 |
Related CAS # | Islatravir;865363-93-5;EFdA-TP tetraammonium;EFdA-TP tetrasodium;2883783-00-2 |
PubChem CID | 44568060 |
Appearance | Typically exists as White to off-white solid at room temperature |
LogP | -4.4 |
Hydrogen Bond Donor Count | 6 |
Hydrogen Bond Acceptor Count | 17 |
Rotatable Bond Count | 9 |
Heavy Atom Count | 33 |
Complexity | 946 |
Defined Atom Stereocenter Count | 3 |
SMILES | C#C[C@]1([C@H](C[C@@H](O1)N2C=NC3=C(N=C(N=C32)F)N)O)COP(=O)(O)OP(=O)(O)OP(=O)(O)O |
InChi Key | BUMPFXRZUYYODO-QRPMWFLTSA-N |
InChi Code | InChI=1S/C12H15FN5O12P3/c1-2-12(4-27-32(23,24)30-33(25,26)29-31(20,21)22)6(19)3-7(28-12)18-5-15-8-9(14)16-11(13)17-10(8)18/h1,5-7,19H,3-4H2,(H,23,24)(H,25,26)(H2,14,16,17)(H2,20,21,22)/t6-,7+,12+/m0/s1 |
Chemical Name | [[(2R,3S,5R)-5-(6-amino-2-fluoropurin-9-yl)-2-ethynyl-3-hydroxyoxolan-2-yl]methoxy-hydroxyphosphoryl] phosphono hydrogen phosphate |
Synonyms | EFdA-TP; EFdA-TP; 950913-56-1; Islatravir triphosphate; 2'-Deoxy-4'-Ethynyl-2-Fluoroadenosine 5'-(Tetrahydrogen Triphosphate); 7HAE2A23SL; CHEMBL518606; 2'-Deoxy-4'-c-ethynyl-2-fluoroadenosine 5'-(tetrahydrogen triphosphate); Adenosine 5'-(tetrahydrogen triphosphate), 2'-deoxy-4'-c-ethynyl-2-fluoro-; |
HS Tariff Code | 2934.99.9001 |
Storage |
Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month |
Shipping Condition | Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs) |
Biological Activity
Targets | HIV-1 |
ln Vitro | As an ICT or DCT, EFdA-TP (0.05–10 μM) inhibits RT-catalyzed DNA synthesis for 15 minutes[1]. As a translocation-defective RT inhibitor that significantly slows down DNA synthesis, EFdA-TP can block RT and function as a de facto immediate chain terminator. Before preventing DNA synthesis, EFdA-TP can act as a delayed chain terminator, permitting the insertion of an extra dNTP[1]. |
ln Vivo | EFdA is active against wild-type (EC50 as low as 50 pmol/l) and most highly NRTI-resistant viruses. The active metabolite, EFdA-triphosphate, has been shown to have a prolonged intracellular half-life in human and rhesus (Rh) blood cells. As a result, single drug doses tested in simian immunodeficiency virus mac251-infected Rh macaques and HIV-1-infected individuals exhibited robust antiviral activity of 7-10 days duration. Preclinical studies of EFdA as preexposure prophylaxis in the Rh macaque/simian/human immunodeficiency virus low-dose intrarectal challenge model have shown complete protection when given in clinically relevant doses[2]. |
Enzyme Assay | 4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is a nucleoside analog that, unlike approved anti-human immunodeficiency virus type 1 (HIV-1) nucleoside reverse transcriptase inhibitors, has a 3'-OH and exhibits remarkable potency against wild-type and drug-resistant HIVs. EFdA triphosphate (EFdA-TP) is unique among nucleoside reverse transcriptase inhibitors because it inhibits HIV-1 reverse transcriptase (RT) with multiple mechanisms. (a) EFdA-TP can block RT as a translocation-defective RT inhibitor that dramatically slows DNA synthesis, acting as a de facto immediate chain terminator. Although non-translocated EFdA-MP-terminated primers can be unblocked, they can be efficiently converted back to the EFdA-MP-terminated form. (b) EFdA-TP can function as a delayed chain terminator, allowing incorporation of an additional dNTP before blocking DNA synthesis. In such cases, EFdA-MP-terminated primers are protected from excision. (c) EFdA-MP can be efficiently misincorporated by RT, leading to mismatched primers that are extremely hard to extend and are also protected from excision. The context of template sequence defines the relative contribution of each mechanism and affects the affinity of EFdA-MP for potential incorporation sites, explaining in part the lack of antagonism between EFdA and tenofovir. Changes in the type of nucleotide before EFdA-MP incorporation can alter its mechanism of inhibition from delayed chain terminator to immediate chain terminator. The versatility of EFdA in inhibiting HIV replication by multiple mechanisms may explain why resistance to EFdA is more difficult to emerge[1]. |
References |
[1]. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) inhibits HIV-1 reverse transcriptase with multiple mechanisms. J Biol Chem. 2014 Aug 29;289(35):24533-48. [2]. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine, MK-8591: a novel HIV-1 reverse transcriptase translocation inhibitor. Curr Opin HIV AIDS. 2018 Jul;13(4):294-299. |
Additional Infomation | 4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is a nucleoside reverse transcriptase inhibitor (NRTI) with a novel mechanism of action, unique structure, and amongst NRTIs, unparalleled anti-HIV-1 activity. We will summarize its structure and function, antiviral activity, resistance profile, and potential as an antiretroviral for use in the treatment and preexposure prophylaxis of HIV-1 infection. Summary: EFdA is a novel antiretroviral with activity against both wild-type and NRTI-resistant viruses. As a result of the prolonged intracellular half-life of its active moiety, it is amenable to flexibility in dosing of at least daily to weekly and perhaps longer.[2] |
Solubility Data
Solubility (In Vitro) | May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples |
Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80: Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 :Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *Preparation of 20% SBE-β-CD in Saline (4°C,1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10: 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300:Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.) |
Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
1 mM | 1.8755 mL | 9.3775 mL | 18.7550 mL | |
5 mM | 0.3751 mL | 1.8755 mL | 3.7510 mL | |
10 mM | 0.1876 mL | 0.9378 mL | 1.8755 mL |