IRF1-IN-1 (Compound I-2) is an IRF1 inhibitor. IRF1-IN-1 reduces the recruitment of IRF1 to the CASP1 promoter. IRF1-IN-1 inhibits cell death signaling pathways (i.e., inhibits the cleavage of Caspase 1, GSDMD, IL-1, and PARP1). IRF1-IN-1 has a protective effect against ionizing radiation-induced skin inflammatory damage.

Physicochemical Properties

Molecular Formula	C22H24N4O4S
Molecular Weight	440.52
CAS #	701225-07-2
Appearance	White to off-white solid powder
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.
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	PARP-1 IL-1 Caspase-1
ln Vitro	Pretreatment with IRF1-IN-1 (20 μM, 12 h) reduces the recruitment of IRF1 to the CASP1 promoter in irradiated HaCaT cells (20 Gy)[1]. IRF1-IN-1 (20 μM, 24 h) attenuates IRF1 activation induced by NSP-10 plasmid transfection in HELF, HaCaT, and WS1 cells[1]. IRF1-IN-1 (50 μM, 24 h) reduces the transcriptional activity of IRF1 in HELF cells 96 h after SARS-CoV-2 pseudovirus infection[1]. IRF1-IN-1 reduces radiation (20 Gy)-induced K150 cell death[1]. IRF1-IN-1 maintains mitochondrial activity and ROS production in skin cells in the early stages after irradiation[1]. IRF1-IN-1 can significantly inhibit the cell death signaling pathway, namely, inhibiting the cleavage of Caspase 1, GSDMD, IL-1 and PARP1 [1].
ln Vivo	IRF1-IN-1 pretreatment (100 μg/d, subcutaneous injection, irradiation every other day) has a potential protective effect against inflammatory skin damage induced by 35 Gy radiation in mice [1].
Animal Protocol	Animal/Disease Models: Radiogenic skin injury mice (intraperitoneal injection of pentobarbital sodium (1%, 30 mg/kg), 35 Gy at the dose rate of 1000 cGy/min by a 6-MeV electron beam)[1] Doses: 100 μg/d Route of Administration: Subcutaneous injection (s.c.), one every other day before irradiation, pretreatment Experimental Results: Showed a significant reduction in acute skin inflammatory manifestations, such as erythema and exudation and accelerated the healing process. Showed protective effects on the function and structural integrity of radiation-induced lesions to the claws.
References	[1]. Chaperone- and PTM-mediated activation of IRF1 tames radiation-induced cell death and the inflammatory response. Cell Mol Immunol. 2024 Aug;21(8):856-872.

Solubility Data

Solubility (In Vitro)

DMSO : ~83.33 mg/mL (~189.16 mM; with ultrasonication)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.2700 mL	11.3502 mL	22.7004 mL
	5 mM	0.4540 mL	2.2700 mL	4.5401 mL
	10 mM	0.2270 mL	1.1350 mL	2.2700 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.