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

MedKoo CAT#: 562416

CAS#: 3039-71-2 (HCl)

Description: U-18666A is an inhibitor of cholesterol synthesis. It acts by inhibiting desmosterol Δ24-reductase. U18666A inhibits classical swine fever virus replication through interference with intracellular cholesterol trafficking. U18666A or other cholesterol transport inhibitor may be considered as the antiviral drug for the treatment of cats with FIP. U18666A accumulated intracellular free cholesterol in the culture of normal medium but not cholesterol-free medium. U18666A also induced reactive oxygen species (ROS) generation in normal medium but much less in cholesterol-free medium.

Chemical Structure

CAS# 3039-71-2 (HCl)

Theoretical Analysis

MedKoo Cat#: 562416
Name: U-18666A
CAS#: 3039-71-2 (HCl)
Chemical Formula: C25H42ClNO2
Exact Mass:
Molecular Weight: 424.06
Elemental Analysis: C, 70.81; H, 9.98; Cl, 8.36; N, 3.30; O, 7.55

Price and Availability

Size Price Availability Quantity
25.0mg USD 250.0 2 Weeks
50.0mg USD 450.0 2 Weeks
100.0mg USD 750.0 2 Weeks
200.0mg USD 1250.0 2 Weeks
500.0mg USD 2250.0 2 Weeks
1.0g USD 3250.0 2 Weeks
2.0g USD 5450.0 2 Weeks
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Related CAS #: 2855-62-1 (free base)   3039-71-2 (HCl)    

Synonym: U-18666A; U 18666A; U18666A; U 18666 A; U-18666-A; NSC-70801; NSC 70801; NSC70801;

IUPAC/Chemical Name: (3S,8R,9S,10R,13S,14S)-3-[2-(diethylamino)ethoxy]-10,13-dimethyl-1,2,3,4,7,8,9,11,12,14,15,16-dodecahydrocyclopenta[a]phenanthren-17-one hydrochloride


InChi Code: InChI=1S/C25H41NO2.ClH/c1-5-26(6-2)15-16-28-19-11-13-24(3)18(17-19)7-8-20-21-9-10-23(27)25(21,4)14-12-22(20)24;/h7,19-22H,5-6,8-17H2,1-4H3;1H/t19-,20-,21-,22-,24-,25-;/m0./s1

SMILES Code: O=C1CC[C@@]2([H])[C@]3([H])CC=C4C[C@@H](OCCN(CC)CC)CC[C@]4(C)[C@@]3([H])CC[C@]12C.[H]Cl

Appearance: 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 water

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in water

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

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
Water 30.0 70.75

Preparing Stock Solutions

The following data is based on the product molecular weight 424.06 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: Doki T, Tarusawa T, Hohdatsu T, Takano T. In Vivo Antiviral Effects of U18666A Against Type I Feline Infectious Peritonitis Virus. Pathogens. 2020 Jan 18;9(1):67. doi: 10.3390/pathogens9010067. PMID: 31963705; PMCID: PMC7169457.

2: Liang XD, Zhang YN, Liu CC, Chen J, Chen XN, Sattar Baloch A, Zhou B. U18666A inhibits classical swine fever virus replication through interference with intracellular cholesterol trafficking. Vet Microbiol. 2019 Nov;238:108436. doi: 10.1016/j.vetmic.2019.108436. Epub 2019 Oct 3. PMID: 31648726.

3: Sabino C, Basic M, Bender D, Elgner F, Himmelsbach K, Hildt E. Bafilomycin A1 and U18666A Efficiently Impair ZIKV Infection. Viruses. 2019 Jun 6;11(6):524. doi: 10.3390/v11060524. PMID: 31174294; PMCID: PMC6630673.

4: Chung J, Phukan G, Vergote D, Mohamed A, Maulik M, Stahn M, Andrew RJ, Thinakaran G, Posse de Chaves E, Kar S. Endosomal-Lysosomal Cholesterol Sequestration by U18666A Differentially Regulates Amyloid Precursor Protein (APP) Metabolism in Normal and APP-Overexpressing Cells. Mol Cell Biol. 2018 May 15;38(11):e00529-17. doi: 10.1128/MCB.00529-17. PMID: 29530923; PMCID: PMC5954187.

5: Takano T, Endoh M, Fukatsu H, Sakurada H, Doki T, Hohdatsu T. The cholesterol transport inhibitor U18666A inhibits type I feline coronavirus infection. Antiviral Res. 2017 Sep;145:96-102. doi: 10.1016/j.antiviral.2017.07.022. Epub 2017 Aug 3. PMID: 28780424; PMCID: PMC7113792.

6: Yang H, Wang Y, Kar S. Effects of cholesterol transport inhibitor U18666A on APP metabolism in rat primary astrocytes. Glia. 2017 Nov;65(11):1728-1743. doi: 10.1002/glia.23191. Epub 2017 Jul 19. PMID: 28722194.

7: Schmitt M, Dehay B, Bezard E, Garcia-Ladona FJ. U18666A, an activator of sterol regulatory element binding protein pathway, modulates presynaptic dopaminergic phenotype of SH-SY5Y neuroblastoma cells. Synapse. 2017 Sep;71(9). doi: 10.1002/syn.21980. Epub 2017 Jun 20. PMID: 28407359.

8: Elgner F, Ren H, Medvedev R, Ploen D, Himmelsbach K, Boller K, Hildt E. The Intracellular Cholesterol Transport Inhibitor U18666A Inhibits the Exosome- Dependent Release of Mature Hepatitis C Virus. J Virol. 2016 Nov 28;90(24):11181-11196. doi: 10.1128/JVI.01053-16. PMID: 27707921; PMCID: PMC5126375.

9: Quach D, Vitali C, La FM, Xiao AX, Millar JS, Tang C, Rader DJ, Phillips MC, Lyssenko NN. Cell lipid metabolism modulators 2-bromopalmitate, D609, monensin, U18666A and probucol shift discoidal HDL formation to the smaller-sized particles: implications for the mechanism of HDL assembly. Biochim Biophys Acta. 2016 Dec;1861(12 Pt A):1968-1979. doi: 10.1016/j.bbalip.2016.09.017. Epub 2016 Sep 24. PMID: 27671775.

10: Quan X, Chen X, Sun D, Xu B, Zhao L, Shi X, Liu H, Gao B, Lu X. The mechanism of the effect of U18666a on blocking the activity of 3β-hydroxysterol Δ-24-reductase (DHCR24): molecular dynamics simulation study and free energy analysis. J Mol Model. 2016 Feb;22(2):46. doi: 10.1007/s00894-016-2907-2. Epub 2016 Jan 27. PMID: 26815033.

11: Lu F, Liang Q, Abi-Mosleh L, Das A, De Brabander JK, Goldstein JL, Brown MS. Identification of NPC1 as the target of U18666A, an inhibitor of lysosomal cholesterol export and Ebola infection. Elife. 2015 Dec 8;4:e12177. doi: 10.7554/eLife.12177. PMID: 26646182; PMCID: PMC4718804.

12: Copetti-Santos D, Moraes V, Weiler DF, de Mello AS, Machado Fde S, Marinho JP, Siebert C, Kolling J, Funchal C, Wyse AT, Coelho JC. U18666A Treatment Results in Cholesterol Accumulation, Reduced Na(+), K(+)-ATPase Activity, and Increased Oxidative Stress in Rat Cortical Astrocytes. Lipids. 2015 Oct;50(10):937-44. doi: 10.1007/s11745-015-4062-4. Epub 2015 Sep 7. PMID: 26344921.

13: Yao K, Wu J, Zhang J, Bo J, Hong Z, Zu H. Protective Effect of DHT on Apoptosis Induced by U18666A via PI3K/Akt Signaling Pathway in C6 Glial Cell Lines. Cell Mol Neurobiol. 2016 Jul;36(5):801-9. doi: 10.1007/s10571-015-0263-x. Epub 2015 Sep 4. PMID: 26340949.

14: Santos DC, da Silva Garcia C, de Andrade CV, Daitx VV, da Costa Moraes V, Rohden F, Coelho JC. Effect of u18666a on beta-glucosidase, sphingomyelinase, and beta-galactosidase activities in astrocytes of young rats. J Membr Biol. 2015 Apr;248(2):215-22. doi: 10.1007/s00232-014-9761-x. Epub 2015 Feb 17. PMID: 25688009.

15: Yamasaki T, Suzuki A, Hasebe R, Horiuchi M. Comparison of the anti-prion mechanism of four different anti-prion compounds, anti-PrP monoclonal antibody 44B1, pentosan polysulfate, chlorpromazine, and U18666A, in prion-infected mouse neuroblastoma cells. PLoS One. 2014 Sep 2;9(9):e106516. doi: 10.1371/journal.pone.0106516. PMID: 25181483; PMCID: PMC4152300.

16: Amritraj A, Wang Y, Revett TJ, Vergote D, Westaway D, Kar S. Role of cathepsin D in U18666A-induced neuronal cell death: potential implication in Niemann-Pick type C disease pathogenesis. J Biol Chem. 2013 Feb 1;288(5):3136-52. doi: 10.1074/jbc.M112.412460. Epub 2012 Dec 17. PMID: 23250759; PMCID: PMC3561536.

17: Poh MK, Shui G, Xie X, Shi PY, Wenk MR, Gu F. U18666A, an intra-cellular cholesterol transport inhibitor, inhibits dengue virus entry and replication. Antiviral Res. 2012 Jan;93(1):191-8. doi: 10.1016/j.antiviral.2011.11.014. Epub 2011 Nov 29. PMID: 22146564.

18: Cenedella RJ. Cholesterol synthesis inhibitor U18666A and the role of sterol metabolism and trafficking in numerous pathophysiological processes. Lipids. 2009 Jun;44(6):477-87. doi: 10.1007/s11745-009-3305-7. Epub 2009 May 14. PMID: 19440746.

19: Iftakhar-E-Khuda I, Koide N, Hassan F, Noman AS, Dagvadorj J, Tumurkhuu G, Naiki Y, Komatsu T, Yoshida T, Yokochi T. Novel mechanism of U18666A-induced tumour necrosis factor-alpha production in RAW 264.7 macrophage cells. Clin Exp Immunol. 2009 Mar;155(3):552-8. doi: 10.1111/j.1365-2249.2008.03779.x. PMID: 19220841; PMCID: PMC2669532.

20: Zheng C, Wang MY, Liu Q, Wakui M, Whiteaker P, Lukas RJ, Wu J. U18666A, a cholesterol-inhibition agent, modulates human neuronal nicotinic acetylcholine receptors heterologously expressed in SH-EP1 cell line. J Neurochem. 2009 Mar;108(6):1526-38. doi: 10.1111/j.1471-4159.2009.05903.x. Epub 2009 Feb 16. PMID: 19183258.


25.0mg / USD 250.0