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

MedKoo CAT#: 319724

CAS#: 1018450-26-4

Description: Fosdevirine, also known as GSK2248761 and IDX899, a Highly Potent Anti-HIV Non-nucleoside Reverse Transcriptase Inhibitor having an EC50 of 11 nM against the Y181C/K103N double mutant. GSK2248761 is a novel, once-daily (QD), next-generation nonnucleoside reverse transcriptase inhibitor (NNRTI) with activity against efavirenz-resistant strains. GSK2248761 at 100 to 800 mg QD for 7 days was well tolerated, demonstrated potent antiviral activity in treatment-naive HIV-infected subjects, and had favorable PK and resistance profiles. GSK2248761 is no longer in clinical development.

Price and Availability




Fosdevirine is not in stock, but may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 319724
Name: Fosdevirine
CAS#: 1018450-26-4
Chemical Formula: C20H17ClN3O3P
Exact Mass: 413.0696
Molecular Weight: 413.7978
Elemental Analysis: C, 58.05; H, 4.14; Cl, 8.57; N, 10.15; O, 11.60; P, 7.49

Synonym: GSK2248761; GSK-2248761; GSK 2248761; GSK2248761A; GSK-2248761A; GSK 2248761A; IDX899; IDX-899; IDX 899, Fosdevirine.

IUPAC/Chemical Name: methyl (E)-(2-carbamoyl-5-chloro-1H-indol-3-yl)(3-(2-cyanovinyl)-5-methylphenyl)phosphinate


InChi Code: InChI=1S/C20H17ClN3O3P/c1-12-8-13(4-3-7-22)10-15(9-12)28(26,27-2)19-16-11-14(21)5-6-17(16)24-18(19)20(23)25/h3-6,8-11,24H,1-2H3,(H2,23,25)/b4-3+

SMILES Code: O=P(C1=CC(C)=CC(/C=C/C#N)=C1)(C2=C(C(N)=O)NC3=C2C=C(Cl)C=C3)OC

Technical Data

Solid powder

>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).

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).

Harmonized System Code:


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