Isatoribine hydrate

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

MedKoo CAT#: 201590

CAS#: 198832-38-1 (hydrate)

Description: Isatoribine (also known as immunosine, or 7-thia-8-oxoguanosine) is a novel guanosine analogue showing immunostimulatory activity both in vivo and in vitro. This compound acts on different components of the immune system including B cells, natural killer (NK) cells and antigen-presenting cells (APC). It was found that immunosine significantly stimulates proliferation of T cells. The effect was dose-dependent and also depended on concentrations of specific stimulators. Maximal stimulation was seen using 250 microM immunosine.

Chemical Structure

Isatoribine hydrate
CAS# 198832-38-1 (hydrate)

Theoretical Analysis

MedKoo Cat#: 201590
Name: Isatoribine hydrate
CAS#: 198832-38-1 (hydrate)
Chemical Formula: C10H14N4O7S
Exact Mass: 316.04775
Molecular Weight: 334.31
Elemental Analysis: C, 35.93; H, 4.22; N, 16.76; O, 33.50; S, 9.59

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Pricing updated 2021-03-07. Prices are subject to change without notice.

Isatoribine hydrate 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.

Related CAS #: 198832-38-1 (hydrate)   122970-40-5 (free base)    

Synonym: ANA245; ANA-245; ANA 245; Immusine; Isatoribine hydrate; Isatoribine monohydrate; D04619; 7-thia-8-oxoguanosine.

IUPAC/Chemical Name: 5-amino-3-((2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrofuran-2-yl)thiazolo[4,5-d]pyrimidine-2,7(3H,6H)-dione hydrate


InChi Code: InChI=1S/C10H12N4O6S.H2O/c11-9-12-6-5(7(18)13-9)21-10(19)14(6)8-4(17)3(16)2(1-15)20-8;/h2-4,8,15-17H,1H2,(H3,11,12,13,18);1H2/t2-,3-,4-,8-;/m1./s1

SMILES Code: O=C(N1[C@@H]2O[C@H](CO)[C@@H](O)[C@H]2O)SC3=C1N=C(N)NC3=O.[H]O[H]

Solid powder


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:
>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:

Handling Instructions:

Preparing Stock Solutions

The following data is based on the product molecular weight 334.31 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.

Select a batch to recalculate based on the batch molecular weight:
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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*When preparing stock solutions always use the batch-specific molecular weight of the product found on the vial label and SDS / CoA (available online).

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Additional Information

Isatoribine is currently developed by Anadys Pharmaceuticals, Inc. According to Anadys's website, is atoribine  is a nucleoside analog currently in evaluating in ongoing clinical trials for the treatment of HCV infections. Isatoribine represents one of a new class of drugs being developed by Anadys to regulate innate immunity, combat HCV infection, and overcome limitations of current anti-HCV therapies. Anadys believes isatoribine interacts with a specific receptor, Toll-like receptor 7, or TLR7, that is present on certain immune system cells. Although results of initial clinical trials may not be predictive of future results, interim results of the Phase 1B clinical trial show that isatoribine is biologically active in adults with chronic HCV infection and results from dosing a cohort of six HCV infected patients with 800mg of isatoribine showed a statistically significant reduction of viral load (p=0.03) at the end of one week, with a median change in viral load from baseline of -0.94 log10 units. Anadys is currently enrolling patients for an isatoribine Phase I/II study.
Current developer:  Anadys Pharmaceuticals, Inc .