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

MedKoo CAT#: 202541

CAS#: 501919-59-1

Description: S3I-201, also known as NSC 74859, is a cell-permeable Stat3 inhibitor that binds to the Stat3-SH2 domain, prevents Stat3 phosphorylation/activation, dimerization, and DNA-binding.

Chemical Structure

CAS# 501919-59-1

Theoretical Analysis

MedKoo Cat#: 202541
Name: S31-201
CAS#: 501919-59-1
Chemical Formula: C16H15NO7S
Exact Mass: 365.05692
Molecular Weight: 365.36
Elemental Analysis: C, 52.60; H, 4.14; N, 3.83; O, 30.65; S, 8.78

Price and Availability

Size Price Availability Quantity
25.0mg USD 135.0 Same day
50.0mg USD 200.0 Same day
100.0mg USD 365.0 Same day
200.0mg USD 650.0 Same day
500.0mg USD 1450.0 Same day
1.0g USD 2250.0 Same day
2.0g USD 3950.0 2 Weeks
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Synonym: NSC 74859; NSC74859; NSC-74859; S3I-201; S3I 20; S3I201.

IUPAC/Chemical Name: 2-hydroxy-4-(2-(tosyloxy)acetamido)benzoic acid


InChi Code: InChI=1S/C16H15NO7S/c1-10-2-5-12(6-3-10)25(22,23)24-9-15(19)17-11-4-7-13(16(20)21)14(18)8-11/h2-8,18H,9H2,1H3,(H,17,19)(H,20,21)

SMILES Code: O=C(O)C1=CC=C(NC(COS(=O)(C2=CC=C(C)C=C2)=O)=O)C=C1O

Appearance: White to off-white 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 soluble 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 365.36 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. Pang M, Ma L, Gong R, Tolbert E, Mao H, Ponnusamy M, Chin YE, Yan H, Dworkin LD, Zhuang S. A novel STAT3 inhibitor, S3I-201, attenuates renal interstitial fibroblast activation and interstitial fibrosis in obstructive nephropathy. Kidney Int. 2010 Aug;78(3):257-68. Epub 2010 Jun 2. PubMed PMID: 20520592.


25.0mg / USD 135.0

Additional Information

In HCC cells with loss of response to TGF-.beta., NSC 74859, a STAT3-specific inhibitor, markedly suppresses growth. In contrast, CD133+ status did not affect the response to STAT3 inhibition: both CD133+ Huh-7 cells and CD133- Huh-7 cells are equally sensitive to NSC 74859 treatment and STAT3 inhibition, with an IC50 of 100 .mu.M. Thus, the TGF-.beta./beta2 spectrin (.beta.2SP) pathway may reflect a more functional 'stem/progenitor' state than CD133. Furthermore, NSC 74859 treatment of Huh-7 xenografts in nude mice significantly retarded tumor growth, with an ED of only 5 mg/kg. Moreover, NSC 74859 inhibited tyrosine phosphorylation of STAT3 in HCC cells in vivo. The authors conclude that inhibiting interleukin 6 (IL6)/STAT3 in HCCs with inactivation of the TGF-.beta./.beta.2SP pathway is an effective approach in management of HCCs. Thus, IL6/STAT3, a major signaling pathway in HCC stem cell renewal and proliferation, can provide a novel approach to the treatment of specific HCCs.  see: Oncogene (2009), 28(7), 961-972.
Current developer :  H. Lee Moffitt Cancer Center & Research Institute, USA; University of South Florida; University of Central Florida