Steroid

This article is about the family of polycyclic compounds. For the drugs, also used as performance-enhancing substances, see Anabolic steroid. For the scientific journal, see Steroids (journal). For the Death Grips EP, see Steroids (Crouching Tiger Hidden Gabber Megamix).

Complex chemical diagram
Structure of 24-ethyl-lanostane, a prototypical steroid with 32 carbon atoms. Its core ring system (ABCD), composed of 17 carbon atoms, is shown with IUPAC-approved ring lettering and atom numbering.[1]: 1785f 

A steroid is an organic compound with four fused rings (designated A, B, C, and D) arranged in a specific molecular configuration.

Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signaling molecules. Examples include the lipid cholesterol, sex hormones estradiol and testosterone,[2]: 10–19  anabolic steroids, and the anti-inflammatory corticosteroid drug dexamethasone.[3] Hundreds of steroids are found in fungi, plants, and animals. All steroids are manufactured in cells from the sterols lanosterol (opisthokonts) or cycloartenol (plants). Lanosterol and cycloartenol are derived from the cyclization of the triterpene squalene.[4]

Steroids are named after the steroid cholesterol[5] which was first described in gall stones from Ancient Greek chole- 'bile' and stereos 'solid'.[6][7][8]

The steroid nucleus (core structure) is called gonane (cyclopentanoperhydrophenanthrene).[9] It is typically composed of seventeen carbon atoms, bonded in four fused rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring). Steroids vary by the functional groups attached to this four-ring core and by the oxidation state of the rings. Sterols are forms of steroids with a hydroxy group at position three and a skeleton derived from cholestane.[1]: 1785f [10] Steroids can also be more radically modified, such as by changes to the ring structure, for example, cutting one of the rings. Cutting Ring B produces secosteroids one of which is vitamin D3.

Filled-in diagram of a steroid
Space-filling representation
Ball-and-stick diagram of the same steroid
Ball-and-stick representation
5α-dihydroprogesterone (5α-DHP), a steroid. The shape of the four rings of most steroids is illustrated (carbon atoms in black, oxygens in red and hydrogens in grey). The nonpolar "slab" of hydrocarbon in the middle (grey, black) and the polar groups at opposing ends (red) are common features of natural steroids. 5α-DHP is an endogenous steroid hormone and a biosynthetic intermediate.
  1. ^ a b Moss GP, the Working Party of the IUPAC-IUB Joint Commission on Biochemical Nomenclature (1989). "Nomenclature of steroids, recommendations 1989" (PDF). Pure Appl. Chem. 61 (10): 1783–1822. doi:10.1351/pac198961101783. S2CID 97612891. Archived (PDF) from the original on 30 November 2012. Retrieved 21 February 2012. Also available with the same authors at "IUPAC-IUB Joint Commission on Biochemical Nomenclature (JCBN). The nomenclature of steroids. Recommendations 1989". European Journal of Biochemistry. 186 (3): 429–458. December 1989. doi:10.1111/j.1432-1033.1989.tb15228.x. PMID 2606099.; Also available online at "The Nomenclature of Steroids". London, GBR: Queen Mary University of London. p. 3S-1.4. Archived from the original on 10 September 2017. Retrieved 10 May 2014.
  2. ^ Lednicer D (2011). Steroid Chemistry at a Glance. Hoboken: Wiley. ISBN 978-0-470-66084-3.
  3. ^ Rhen T, Cidlowski JA (October 2005). "Antiinflammatory action of glucocorticoids--new mechanisms for old drugs". The New England Journal of Medicine. 353 (16): 1711–1723. doi:10.1056/NEJMra050541. PMID 16236742. S2CID 5744727.
  4. ^ "Lanosterol biosynthesis". Recommendations on Biochemical & Organic Nomenclature, Symbols & Terminology. International Union Of Biochemistry And Molecular Biology. Archived from the original on 8 March 2011. Retrieved 28 November 2006.
  5. ^ Harper D. "sterol | Etymology, origin and meaning of sterol by etymonline". Online Etymology Dictionary. Archived from the original on 19 March 2023. Retrieved 19 March 2023.
  6. ^ Chevreul ME (8 May 1815). "Recherches chimiques sur les corps gras, et particulièrement sur leurs combinaisons avec les alcalis. Sixième mémoire. Examen des graisses d'homme, de mouton, de boeuf, de jaguar et d'oie" [Chemical research on fatty substances, and particularly on their combinations with alkalis. Sixth memoir. Examination of human, sheep, beef, jaguar and goose fats]. Annales de Chimie et de Physique (Annals of Chemistry and Physics) (in French). 2: 339–372. Archived from the original on 4 October 2023. Retrieved 11 September 2023 – via Deutsche Digitale Bibliothek.
  7. ^ Arago F, Gay-Lussac JL (1816). Annales de chimie et de physique (Annals of Chemistry and Physics) (in French). Chez Crochard. p. 346. "Je nommerai cholesterine, de χολη, bile, et στερεος, solide, la substance cristallisée des calculs biliares humains, ... " (I will name cholesterine – from χολη (bile) and στερεος (solid) – the crystalized substance from human gallstones ... )
  8. ^ "R-2.4.1 Fusion nomenclature". Archived from the original on 22 November 2023. Retrieved 22 November 2023.
  9. ^ Yang Y, Krin A, Cai X, Poopari MR, Zhang Y, Cheeseman JR, Xu Y (January 2023). "Conformations of Steroid Hormones: Infrared and Vibrational Circular Dichroism Spectroscopy". Molecules. 28 (2): 771. doi:10.3390/molecules28020771. PMC 9864676. PMID 36677830.
  10. ^ Also available in print at Hill RA, Makin HL, Kirk DN, Murphy GM (1991). Dictionary of Steroids. London, GBR: Chapman and Hall. pp. xxx–lix. ISBN 978-0-412-27060-4. Retrieved 20 June 2015.