{{Chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 443869216 | ImageFile = Eicosane.png | ImageFile_Ref = {{chemboximage|correct|??}} | ImageSize = 300 | ImageClass = skin-invert | ImageAlt = Structural formula of icosane | ImageFile1 = Icosane 3D ball.png | ImageFile1_Ref = {{chemboximage|correct|??}} | ImageSize1 = 300 | ImageClass1 = bg-transparent | ImageAlt1 = Ball and stick model of the icosane molecule | PIN = Icosane<ref>{{cite book |author=International Union of Pure and Applied Chemistry |date=2014 |title=Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 |publisher=The Royal Society of Chemistry |pages=59 |doi=10.1039/9781849733069 |isbn=978-0-85404-182-4}}</ref> | OtherNames = ''n''-Eicosane, Eichosane |Section1={{Chembox Identifiers | CASNo = 112-95-8 | CASNo_Ref = {{cascite|correct|CAS}} | PubChem = 8222 | ChemSpiderID = 7929 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | UNII = 3AYA9KEC48 | UNII_Ref = {{fdacite|correct|FDA}} | EINECS = 204-018-1 | MeSHName = eicosane | ChEBI = 43619 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEMBL = 1233983 | ChEMBL_Ref = {{ebicite|changed|EBI}} | Beilstein = 1700722 | SMILES = CCCCCCCCCCCCCCCCCCCC | StdInChI = 1S/C20H42/c1-3-5-7-9-11-13-15-17-19-20-18-16-14-12-10-8-6-4-2/h3-20H2,1-2H3 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = CBFCDTFDPHXCNY-UHFFFAOYSA-N | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} }} |Section2={{Chembox Properties | C=20 | H=42 | Appearance = Colorless, waxy crystals | Odor = Odorless | MeltingPtK = 309 to 311 | BoilingPtK = 616.2 | LogP = 10.897 | HenryConstant = 31 μmol Pa<sup>−1</sup> kg<sup>−1</sup> }} |Section3={{Chembox Thermochemistry | Entropy = 558.6 J K<sup>−1</sup> mol<sup>−1</sup> | HeatCapacity = 602.5 J K<sup>−1</sup> mol<sup>−1</sup> (at 6.0&nbsp;°C) }} |Section4={{Chembox Hazards | GHSPictograms = {{GHS08}} | GHSSignalWord = Danger | HPhrases = {{H-phrases|304}} | PPhrases = {{P-phrases|301+316|331|405|501}} | FlashPt = > | FlashPtC = 113 | NFPA-F = 1 | NFPA-H = 0 | NFPA-R = 0 }} |Section5={{Chembox Related | OtherFunction_label = alkanes | OtherFunction = {{Unbulleted list|Nonadecane|Heneicosane}} }} }} '''Eicosane''' (alternative spellings '''icosane''' and '''eichosane'''<ref>{{cite book |last1=Vargaftik |first1=N. B. |title=Handbook of physical properties of liquids and gases: pure substances and mixtures |date=1983 |publisher=Hemisphere Pub. Corp |location=Washington |isbn=9780891163565 |edition=2nd}}</ref>) is an alkane with the chemical formula C<sub>20</sub>H<sub>42</sub>. It has 366,319 constitutional isomers.<ref>{{Cite web | last = NMPPDB | title = "NMPC‑1133 (Humulene epoxide) – Nigerian Medicinal Plants & Phytochemicals Database" | url = https://nmppdb.com.ng/compounds-detail?compound=1133 | publisher = NMPPDB | access-date= 2025-06-24}}</ref>

''n''-Eicosane (the straight-chain structural isomer of eicosane) is the shortest compound found in paraffin waxes, used to form candles. It can be isolated from agave attenuate leaves. It is also found in ''Vanilla madagascariensis'' and ''Gymnodinium nagasakiense''.<ref name="Pubchem">[https://pubchem.ncbi.nlm.nih.gov/compound/Eicosane Eicosane Pubchem]</ref>

Eicosane's size, state and chemical inactivity do not exclude it from the traits of its smaller alkane counterparts. It is a colorless or white, non-polar molecule, nearly unreactive except when it burns. It is less dense than and insoluble in water. Its non-polar trait means it can only perform weak intermolecular bonding (hydrophobic/van der Waals forces).

Eicosane's phase transition at a moderate temperature makes it a candidate phase change material, or PCM, which can be used to store thermal energy and control temperature.

It can be detected in the body odor of persons suffering from Parkinson's disease.<ref>{{cite journal |last1= Trivedi|first1= Drupad K.|last2= Sinclair|first2= Eleanor|last3= Xu|first3= Yun|last4= Sarkar|first4= Depanjan|last5= Walton-Doyle|first5= Caitlin|last6= Liscio|first6= Camilla|last7= Banks|first7= Phine|last8= Milne|first8= Joy|last9= Silverdale|first9= Monty|last10= Kunath|first10= Tilo|last11= Goodacre|first11= Royston|last12= Barran|first12= Perdita|title= Discovery of Volatile Biomarkers of Parkinson's Disease from Sebum|journal= ACS Central Science|year= 2019|volume= 5|issue= 4|pages= 599–606|doi=10.1021/acscentsci.8b00879 |doi-access=free|pmid= 31041379|pmc= 6487537}}</ref>

==Naming== It is derived from ἐίκοσι (''eikosi''), Greek for 20 (cf. ''icosahedron'').

IUPAC currently recommends '''icosane''',<ref name=IUPAC1>{{cite web|url=http://www.acdlabs.com/iupac/nomenclature/93/r93_328.htm|title=Table 11 Basic numerical terms (multiplying affixes)|publisher=IUPAC|access-date=2011-02-16}}</ref> whereas Chemical Abstracts Service and Beilstein use '''eicosane'''.<ref name=IUPAC2>{{cite web|url=http://www.acdlabs.com/iupac/nomenclature/93/r93_332.htm|title=Footnote for Table 11|publisher=IUPAC|access-date=2011-02-16}}</ref>

== See also ==

* Perillaldehyde

==References== {{Reflist}}

==External links== * [https://web.archive.org/web/20150923173912/http://www.ars-grin.gov/cgi-bin/duke/chemical.pl?EICOSANE Icosane] at Dr. Duke's Phytochemical and Ethnobotanical Databases {{Alkanes}}

Category:Alkanes