Cyclodiol Explained

Cyclodiol (developmental code name ZK-115194; also known as 14α,17α-ethano-17β-estradiol) is a synthetic estrogen which was studied in the 1990s and was never marketed.^{[1] [2] [3]} It is a derivative of estradiol with a bridge between the C14α and C17α positions. Cyclodiol has 100% of the relative binding affinity of estradiol for the human ERα and similar transactivational capacity as estradiol at the receptor. It has comparable potency to estradiol when administered by subcutaneous injection. The drug shows genotoxicity similarly to estradiol.^[4] Cyclodiol showed an absolute bioavailability of 33 ± 19% and an elimination half-life of 28.7 hours in pharmacokinetic studies in women.

See also

• List of estrogens § Estradiol derivatives
• Cyclotriol

Notes and References

1. Book: Oettel M, Schillinger E . Estrogens and Antiestrogens II: Pharmacology and Clinical Application of Estrogens and Antiestrogen. 6 December 2012. Springer Science & Business Media. 978-3-642-60107-1. 10,15,76,329,332.
2. Baumann A, Fuhrmeister A, Brudny-Klöppel M, Draeger C, Bunte T, Kuhnz W . Comparative pharmacokinetics of two new steroidal estrogens and ethinylestradiol in postmenopausal women . Contraception . 54 . 4 . 235–242 . October 1996 . 8922877 . 10.1016/S0010-7824(96)00194-1 .
3. Lang R, Reimann R . Studies for a genotoxic potential of some endogenous and exogenous sex steroids. I. Communication: examination for the induction of gene mutations using the Ames Salmonella/microsome test and the HGPRT test in V79 cells . Environmental and Molecular Mutagenesis . 21 . 3 . 272–304 . 1993 . 8462531 . 10.1002/em.2850210311 . 39049586 .
4. Hundal BS, Dhillon VS, Sidhu IS . Genotoxic potential of estrogens . Mutation Research . 389 . 2–3 . 173–181 . March 1997 . 9093381 . 10.1016/S1383-5718(96)00144-1 .