Last modified: Tue Jul 6 10:39:45 BST 2004

Steroid carbon nomenclature

Trivial names: 20-Hydroxyecdysone; ß-Ecdysone; Ecdysterone; Insect moulting hormone; Polypodine A
Systematic name: 2ß,3ß,14alpha,20ß,22,25-Hexahydroxycholest-7-en-6-one
Molecular formula: C27H44O7
CAS Number: 5289-74-7
Merck Index (11th Ed) Number: 3465


Pathway: Ecdysone -> 20-Hydroxyecdysone
Reaction: steroid hydroxylation at C20
Enzyme: ecdysone 20-monooxygenase


  1. Srivatsan, J., Weirich, M. and Agosin, M. (1990) Cytochrome P-450-catalyzed formation of 20-hydroxy-ecdysone in larval housefly mitochondria. Biochem. Biophys. Res. Commun. 166, 1372-1377.
  2. Chen, J.H., Hara, T., Fisher, M.J. and Rees, H.H. (1994) Immunological analysis of developmental changes in ecdysone 20-mono-oxygenase expression in the cotton leafworm, Spodoptera littoralis. Biochem. J. 299, 711-717.

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