A secosteroid (sec·o·ster·oid, sek'ō-stēr'oyd) is a type of steroid with a "broken" ring. The word secosteroid derives from the verb Latin: secare meaning "to cut",:241 and Latin: stere of steroid, meaning "solid, three-dimensional".:129 Secosteroids are alternatively described as a subclass of steroids or derived from steroids.
Types or subclasses of secosteroids are defined by the carbon atoms of the parent steroid skeleton where the ring cleavage has taken place. For example, 9,10-secosteroids derived from cleavage of the bond between carbon atoms C9 and C10 of the steroid B-ring (similarly 5,6-secosteroids, 13,14-steroids, etc.).
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- Moss GP and the Working Party of the IUPAC-IUB Joint Commission on Biochemical Nomenclature. "The Nomenclature of Steroids". Queen Mary University of London. p. Section 3S-1 (esp. 3S-1.4, incl. note 4).; Moss GP (1989). "Nomenclature of Steroids (Recommendations 1989)". Pure & Appl. Chem. 61 (10): 1786f. doi:10.1351/pac198961101783.
Steroids are compounds possessing the skeleton of cyclopenta[a]phenanthrene or a skeleton derived therefrom by one or more bond scissions or ring expansions or contractions.; Hill RA; Makin HL; Kirk DN; Murphy GM (1991). Dictionary of Steroids (1st ed.). London: Chapman & Hall. ISBN 978-0-412-27060-4.
- "Definition of secosteroid". Farlex Partner Medical Dictionary. TheFreeDictionary.com.
A compound derived from a steroid in which there has been a ring cleavage.
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