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MedKoo CAT#: 562416

CAS#: 3039-71-2

Description: U-18666A is an inhibitor of cholesterol synthesis. It acts by inhibiting desmosterol Δ24-reductase.

Price and Availability

Size Price Shipping out time Quantity
5mg USD 190 2 Weeks
10mg USD 320 2 Weeks
25mg USD 620 2 Weeks
Inquire bulk and customized quantity

Pricing updated 2020-09-23. Prices are subject to change without notice.

U-18666A, 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.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 562416
Name: U-18666A
CAS#: 3039-71-2
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

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

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

Shelf Life:
>2 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).

HS Tariff Code:


1: 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. PubMed PMID: 28407359.

2: Formichi P, Battisti C, De Santi MM, Guazzo R, Tripodi SA, Radi E, Rossi B, Tarquini E, Federico A. Primary cilium alterations and expression changes of Patched1 proteins in niemann-pick type C disease. J Cell Physiol. 2018 Jan;233(1):663-672. doi: 10.1002/jcp.25926. Epub 2017 May 19. PubMed PMID: 28332184.

3: Petersen W, Stenzel W, Silvie O, Blanz J, Saftig P, Matuschewski K, Ingmundson A. Sequestration of cholesterol within the host late endocytic pathway restricts liver-stage Plasmodium development. Mol Biol Cell. 2017 Mar 15;28(6):726-735. doi: 10.1091/mbc.E16-07-0531. Epub 2017 Jan 25. PubMed PMID: 28122820; PubMed Central PMCID: PMC5349780.

4: Seebacher NA, Richardson DR, Jansson PJ. A mechanism for overcoming P-glycoprotein-mediated drug resistance: novel combination therapy that releases stored doxorubicin from lysosomes via lysosomal permeabilization using Dp44mT or DpC. Cell Death Dis. 2016 Dec 1;7(12):e2510. doi: 10.1038/cddis.2016.381. PubMed PMID: 27906178; PubMed Central PMCID: PMC5261000.

5: Bae YU, Huh JW, Kim BK, Park HY, Seu YB, Doh KO. Enhancement of liposome mediated gene transfer by adding cholesterol and cholesterol modulating drugs. Biochim Biophys Acta. 2016 Dec;1858(12):3017-3023. doi: 10.1016/j.bbamem.2016.09.013. Epub 2016 Sep 21. PubMed PMID: 27664498.

6: 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. Print 2016 Dec 15. PubMed PMID: 27707921; PubMed Central PMCID: PMC5126375.

7: 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. PubMed PMID: 27671775.

8: Gutierrez EM, Seebacher NA, Arzuman L, Kovacevic Z, Lane DJ, Richardson V, Merlot AM, Lok H, Kalinowski DS, Sahni S, Jansson PJ, Richardson DR. Lysosomal membrane stability plays a major role in the cytotoxic activity of the anti-proliferative agent, di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT). Biochim Biophys Acta. 2016 Jul;1863(7 Pt A):1665-81. doi: 10.1016/j.bbamcr.2016.04.017. Epub 2016 Apr 19. PubMed PMID: 27102538.

9: Jiang B, Himmelsbach K, Ren H, Boller K, Hildt E. Subviral Hepatitis B Virus Filaments, like Infectious Viral Particles, Are Released via Multivesicular Bodies. J Virol. 2015 Dec 30;90(7):3330-41. doi: 10.1128/JVI.03109-15. PubMed PMID: 26719264; PubMed Central PMCID: PMC4794700.

10: 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. pii: e12177. doi: 10.7554/eLife.12177. PubMed PMID: 26646182; PubMed Central PMCID: PMC4718804.

11: Hernández-Jiménez M, Martínez-López D, Gabandé-Rodríguez E, Martín-Segura A, Lizasoain I, Ledesma MD, Dotti CG, Moro MA. Seladin-1/DHCR24 Is Neuroprotective by Associating EAAT2 Glutamate Transporter to Lipid Rafts in Experimental Stroke. Stroke. 2016 Jan;47(1):206-13. doi: 10.1161/STROKEAHA.115.010810. Epub 2015 Dec 1. PubMed PMID: 26628388.

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. PubMed 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. PubMed PMID: 26340949.

14: Haque A, Hober D, Blondiaux J. Addressing Therapeutic Options for Ebola Virus Infection in Current and Future Outbreaks. Antimicrob Agents Chemother. 2015 Oct;59(10):5892-902. doi: 10.1128/AAC.01105-15. Epub 2015 Jul 27. Review. PubMed PMID: 26248374; PubMed Central PMCID: PMC4576072.

15: Chen Y, Arnal-Levron M, Lagarde M, Moulin P, Luquain-Costaz C, Delton I. THP1 macrophages oxidized cholesterol, generating 7-derivative oxysterols specifically released by HDL. Steroids. 2015 Jul;99(Pt B):212-8. doi: 10.1016/j.steroids.2015.02.020. Epub 2015 Mar 2. PubMed PMID: 25742736.

16: 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. PubMed PMID: 25688009.

17: Da Ros M, Hirvonen N, Olotu O, Toppari J, Kotaja N. Retromer vesicles interact with RNA granules in haploid male germ cells. Mol Cell Endocrinol. 2015 Feb 5;401:73-83. doi: 10.1016/j.mce.2014.11.026. Epub 2014 Dec 5. PubMed PMID: 25486514.

18: 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. eCollection 2014. PubMed PMID: 25181483; PubMed Central PMCID: PMC4152300.

19: Eltoukhy AA, Sahay G, Cunningham JM, Anderson DG. Niemann-Pick C1 affects the gene delivery efficacy of degradable polymeric nanoparticles. ACS Nano. 2014 Aug 26;8(8):7905-13. doi: 10.1021/nn501630h. Epub 2014 Jul 16. PubMed PMID: 25010491; PubMed Central PMCID: PMC4148171.

20: Fletcher R, Gribben C, Ma X, Burchfield JG, Thomas KC, Krycer JR, James DE, Fazakerley DJ. The role of the Niemann-Pick disease, type C1 protein in adipocyte insulin action. PLoS One. 2014 Apr 21;9(4):e95598. doi: 10.1371/journal.pone.0095598. eCollection 2014. Erratum in: PLoS One. 2014;9(12):e116042. Ma, Xuiquan [corrected to Ma, Xiuquan]. PLoS One. 2014;9(7):e103797. PubMed PMID: 24752197; PubMed Central PMCID: PMC3994084.