delta6D in ABMC-7 cells (IC50 = 0.015 μM); delta6D in Liver microsomes (IC50 = 0.56 μM); delta5D in ABMC-7 cells (IC50 = 0.67 μM); delta5D in ABMC-7 cells (IC50 = 3.4 μM)

CP-24879 (hydrochloride) (0-10 μM, 4 days) inhibits Δ6 + Δ5 desaturase activities in a concentration-dependent manner, with a concentration-dependent depletion of AA and a reduction in LTC4 production[1].
CP-24879 (hydrochloride) (0-10 μM, 16 h) exhibits inhibitory effects on triglyceride accumulation brought on by oleic acid in hepatocytes[2].
In a concentration-dependent manner, CP-24879 (hydrochloride) ((0-10 μM, 16 h) inhibits LPS-induced expression of inflammatory cytokines[2].
CP-24879 (hydrochloride) (0-2 μM, 4 h) inhibits desaturase activity and ameliorates ferroptosis[3].

CP-24879 (hydrochloride) (3 mg/kg, IP, three times per day, for six or four days) inhibits Δ6 + Δ5 desaturase activities in vivo, depleting AA in the livers of mice fed chow while preventing repletion in the livers of mice with EFAD[1].
CP-24879 (hydrochloride) (33 mg/kg, IV, once) is cleared quite quickly and has a relatively short half-life[1].

CP-24879 (p-isopentoxyaniline), an aniline derivative, was identified as a mixed delta5/delta6 desaturase inhibitor during the screening of chemical and natural product libraries. In mouse mastocytoma ABMC-7 cells cultured chronically with CP-24879, there was a concentration-dependent inhibition of desaturase activity that correlated with the degree of depletion of AA and decreased production of leukotriene C4 (LTC4). Production of LTC4 was restored by stimulating the cells in the presence of exogenous AA, indicating that endogenous AA was limiting as substrate. [1]

A combined Δ5D/Δ6D inhibitor, CP-24879, significantly reduced intracellular lipid accumulation and inflammatory injury in hepatocytes. Interestingly, CP-24879 exhibited superior antisteatotic and anti-inflammatory actions in fat-1 and ω-3-treated hepatocytes. Hepatocytes were incubated with CP-24879, a specific Δ5/Δ6 desaturase inhibitor,17 CAY10566, a selective Δ9 desaturase inhibitor,18 EPA or resolvin D1 (RvD1) as detailed in online supplementary material and methods[2]

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We next employed SC-26196, a selective FADS2 inhibitor, and CP-24879, a FADS1/FADS2 dual inhibitor. Since several inhibitors often possess intrinsic antioxidant activity, we first measured the scavenging capacity of FADS inhibitors toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) under cell-free conditions. Similar to the results of a previous report, ferrostatin-1 showed free radical scavenging activity at concentrations of 10 to 50 μM under our experimental conditions. While SC-26196 displayed no antioxidant potential, high concentrations of CP-24879 scavenged 60% of the DPPH radical within 30 min (SI Appendix, Fig. S5). To exclude the antioxidant effect of CP-24879, inhibitors were used at a low concentration (5 μM) with no in vitro antioxidant activity in subsequent experiments. The inhibition of desaturase activity by the SC-26196 or CP-24879 treatment dramatically reduced the cytotoxicity induced by RSL3 (Fig. 4 A and B). Furthermore, RSL3-induced lipid peroxidation was noticeably decreased in the presence of SC-26196 or CP-24879 (Fig. 4C). We next assessed whether the PUFA biosynthesis pathway was also required for ferroptosis under GSH depletion conditions. First, cysteine/methionine deprivation-induced ferroptosis was ameliorated in ELOVL5- or FADS1-depleted cells (Fig. 4D). In addition, SC-26196 or CP-24879 suppressed cell death under cysteine/methionine deprivation conditions (Fig. 4E). Based on these data, PUFA biosynthesis enzymes play essential roles in lipid peroxidation and ferroptosis.[3]

In the livers of mice treated chronically with the maximally tolerated dose of CP-24879 (3 mg/kg, t.i.d.), combined delta5/delta6 desaturase activities were inhibited approximately 80% and AA was depleted nearly 50%. These results suggest that delta5 and/or delta6 desaturase inhibitors have the potential to manifest an anti-inflammatory response by decreasing the level of AA and the ensuing production of eicosanoids.[1]

[1]. Identification and characterization of a novel delta6/delta5 fatty acid desaturase inhibitor as a potential anti-inflammatory agent. Biochem Pharmacol. 1998 Apr 1;55(7):1045-58.

[2]. Molecular interplay between Δ5/Δ6 desaturases and long-chain fatty acids in the pathogenesis of non-alcoholic steatohepatitis. Gut. 2014 Feb;63(2):344-55.

[3]. Polyunsaturated fatty acid biosynthesis pathway determines ferroptosis sensitivity in gastric cancer. Proc Natl Acad Sci U S A. 2020;117(51):32433-32442.

The anti-inflammatory properties of essential fatty acid deficiency or n-3 polyunsaturated fatty acid supplementation are thought to be associated with reduced arachidonic acid (AA; 20:4 n-6) levels. Another plausible approach to reducing AA levels is to selectively inhibit Δ5 and/or Δ6 fatty acid desaturases, thereby reducing endogenous AA synthesis. Researchers have developed a high-throughput radioimmunoassay for quantifying the activities of Δ5, Δ6, and Δ9 desaturases in vitro and in vivo. During the screening of chemical and natural product libraries, researchers discovered that the aniline derivative CP-24879 (p-isopentoxyaniline) is a mixed-type Δ5/Δ6 desaturase inhibitor. In mouse mast cell tumor ABMC-7 cells cultured long-term with CP-24879, desaturase activity was inhibited in a concentration-dependent manner, and the degree of inhibition was correlated with reduced arachidonic acid (AA) consumption and leukotriene C4 (LTC4) production. LTC4 production was restored after cell stimulation with exogenous AA, indicating that endogenous AA is a limiting substrate. In the livers of mice treated with the maximum tolerated dose of CP-24879 (3 mg/kg, three times daily) for an extended period, the total activity of Δ5/Δ6 desaturases was inhibited by approximately 80%, and AA consumption was nearly 50%. These results suggest that Δ5 and/or Δ6 desaturase inhibitors may exert their anti-inflammatory effects by reducing arachidonic acid (AA) levels and the subsequent production of eicosate. [1]

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We used oligonucleotide microarray analysis to find that genes involved in the multi-step catalysis of long-chain polyunsaturated fatty acids, namely Δ-5 desaturases (Δ5D) and Δ6D, were significantly enriched in non-alcoholic steatohepatitis (NASH). In the livers of high-fat diet-induced obese and NASH mice, we confirmed that the expression of Δ5D and Δ6D was increased at both the mRNA and protein levels. Gas chromatography analysis showed that the desaturation flux of the ω-6 and ω-3 pathways was impaired in fatty livers of humans and mice, resulting in an increased ω-6/ω-3 ratio and a decreased ω-3 index. Restoring liver ω-3 content in transgenic fat-1 mice expressing ω-3 desaturase (which converts endogenous ω-6 to ω-3 fatty acids) significantly reduced hepatic insulin resistance, steatosis, macrophage infiltration, necrotizing inflammation, and lipid peroxidation, accompanied by a decrease in the expression of genes related to inflammation, fatty acid uptake, and adipogenesis. Feeding obese mice with an exogenous diet rich in ω-3 largely replicated these results. The combined Δ5D/Δ6D inhibitor CP-24879 significantly reduced lipid accumulation and inflammatory damage in hepatocytes. Interestingly, CP-24879 showed superior anti-steatodegenerative and anti-inflammatory effects in hepatocytes treated with fat-1 and ω-3. Conclusion: These findings suggest that impaired fatty acid desaturation in the liver and an imbalance in the ω-6 to ω-3 ratio play a role in the pathogenesis of non-alcoholic steatohepatitis (NASH). [2]

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Ferroprelation is an iron-dependent, lipid peroxidation-mediated regulatory necrosis. Cancer cells survive under metabolic stress by altering lipid metabolism, which may alter their sensitivity to ferroptosis. However, the association between lipid metabolism and ferroptosis has not been fully elucidated. In this study, we found that the upregulation of very long chain fatty acid extension protein 5 (ELOVL5) and fatty acid desaturase 1 (FADS1) in mesenchymal gastric cancer cells (GC) led to enhanced ferroptosis sensitivity. Conversely, the activity of these enzymes in intestinal glucocorticoid cells (GCs) was inhibited by DNA methylation, resulting in cell resistance to ferroptosis. Lipid profiling and isotope tracing analysis showed that intestinal glucocorticoid cells were unable to utilize linoleic acid to generate arachidonic acid (AA) and adrenaline (AdA). AA supplementation restored the ferroptosis sensitivity of intestinal glucocorticoid cells. Based on these data, the polyunsaturated fatty acid (PUFA) biosynthesis pathway plays a crucial role in ferroptosis; therefore, this pathway may become a biomarker for predicting the efficacy of ferroptosis-mediated cancer treatments. [3]

C11H18CLNO

215.721

215.107

C, 61.25; H, 8.41; Cl, 16.43; N, 6.49; O, 7.42

10141-51-2

10141-51-2

16078965

Brown to black solid powder

322.1ºC at 760 mmHg

154-159ºC

148.6ºC

0.000208mmHg at 25°C

4.076

2

2

4

14

128

0

CC(C)CCOC1=CC=C(C=C1)N.Cl

GFESZSNFRSACMU-UHFFFAOYSA-N

InChI=1S/C11H17NO.ClH/c1-9(2)7-8-13-11-5-3-10(12)4-6-11;/h3-6,9H,7-8,12H2,1-2H3;1H

4-(3-methylbutoxy)aniline;hydrochloride

CP 24879 hydrochloride; CP24879 hydrochloride; CP-24879 hydrochloride; CP 24,879 (hydrochloride); CP-24879 (hydrochloride); 4-(3-methylbutoxy)aniline hydrochloride; Benzenamine, 4-(3-methylbutoxy)-, hydrochloride (9CI); p-(Isoamyloxy)aniline hydrochloride; p-(Isopentyloxy)-aniline; . CP-24879 hydrochloride

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: ~43 mg/mL (~199.3 mM)
Ethanol: ~43 mg/mL (~199.3 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (11.59 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 25.0 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.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (9.64 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in 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 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)