Necrostatin-34 (Nec-34) is an inhibitor (blocker/antagonist) of RIPK1 kinase that stabilizes RIPK1 in an inactive state by occupying a specific binding pocket in the kinase domain.

Physicochemical Properties

Molecular Formula	C18H16N4O2S2
Molecular Weight	384.48
Exact Mass	384.071
CAS #	375835-43-1
PubChem CID	3841655
Appearance	Off-white to light yellow solid powder
Density	1.4±0.1 g/cm3
Index of Refraction	1.675
LogP	0.968
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	5
Heavy Atom Count	26
Complexity	634
Defined Atom Stereocenter Count	0
InChi Key	LOQIRQHGJVGIEL-UHFFFAOYSA-N
InChi Code	InChI=1S/C18H16N4O2S2/c1-11-2-4-12(5-3-11)13-8-15(23)21-17(14(13)9-19)26-10-16(24)22-18-20-6-7-25-18/h2-7,13H,8,10H2,1H3,(H,21,23)(H,20,22,24)
Chemical Name	2-[[5-cyano-4-(4-methylphenyl)-2-oxo-3,4-dihydro-1H-pyridin-6-yl]sulfanyl]-N-(1,3-thiazol-2-yl)acetamide
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: This product requires protection from light (avoid light exposure) during transportation and storage.
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	RIPK1
ln Vitro	Necrostatin-34 (Nec-34) in FADD def-Jurkat cells and L939 cells had IC50 values for TNFα of 667 nM and 134 nM, respectively[1]. The phosphorylation of RIPK1's Ser166 (p-S166), a biomarker for RIPK1 activation, indicates that necrostatin-34 (Nec-34, 10 μM) suppresses the dimerization-induced RIPK1 activation[1]. Necrostatin-34 (Nec-34) has the potential to prevent TNFα-induced complex II formation by impeding RIPK1 kinase activation[1].
Cell Assay	Western Blot Analysis[1] Cell Types: RIPK1 knockout L929 cells transfected with an expressing vector encoding an inducible and dimerizable RIPK1 fused with FKBP at the C-terminus. Tested Concentrations: 10 μM. Incubation Duration: 30 min (and then 100 ng/mL TNFα was added for indicated periods of time). Experimental Results: Downregulated p-S166 levels.
References	[1]. Discovery of a cooperative mode of inhibiting RIPK1 kinase. Cell Discov. 2021 Jun 1;7(1):41.

Solubility Data

Solubility (In Vitro)

DMSO : 125 mg/mL (325.11 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (5.41 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.08 mg/mL (5.41 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.6009 mL	13.0046 mL	26.0092 mL
	5 mM	0.5202 mL	2.6009 mL	5.2018 mL
	10 mM	0.2601 mL	1.3005 mL	2.6009 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.