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.

Price and Availability


USD 650
USD 2950

USD 1050
USD 3950

USD 1950
USD 6250

S31-201, purity > 98%, is in stock. Current shipping out time is about 2 weeks after order is received. CoA, QC data and MSDS documents are available in one week after order is received. Delivery time: overnight (USA/Canada); 3-5 days (worldwide). Shipping fee: from $30.00 (USA); from $45.00 (Canada); from $70.00 (international).

Chemical Structure


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

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

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 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).

Harmonized System Code:

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


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.