RU-16117 is an
estrogen, or an
agonist of the
estrogen receptor (ER).[1][2] In
mouseuterinetissue, it shows about 5 to 13% of the
affinity of
estradiol for the ER and about 1% of the
estrogenic activity of estradiol.[2][3][4] Conversely, it shows no affinity for the
androgen,
progesterone,
glucocorticoid, and
mineralocorticoid receptors, nor any activities associated with interactions with these receptors.[2][5][3][4] While the association rate of RU-16117 to the ER is the same as that of
moxestrol, it dissociates from the ER extremely rapidly at rates of about three times faster than estradiol and about 20 times faster than moxestrol.[1][6] This is similar to the case of
estriol, which RU-16117 is described as sharing similarities with.[1][6] RU-16117 is described as a weak or
partial estrogen or a mixed estrogen/
antiestrogen.[1][2] It has been described as having highly active
antiestrogenic activity with very weak
uterotrophic activity.[7][2] However, higher doses and/or prolonged administration of RU-16117 have been reported to induce equivalent estrogenic responses relative to estradiol and moxestrol.[1][6]
Relative affinities (%) of RU-16117 and related steroids[5][8][3]
Values are percentages (%). Reference
ligands (100%) were
progesterone for the
PRTooltip progesterone receptor,
testosterone for the
ARTooltip androgen receptor,
E2 for the
ERTooltip estrogen receptor,
DEXATooltip dexamethasone for the
GRTooltip glucocorticoid receptor,
aldosterone for the
MRTooltip mineralocorticoid receptor,
DHTTooltip dihydrotestosterone for
SHBGTooltip sex hormone-binding globulin, and
cortisol for
CBGTooltip Corticosteroid-binding globulin.
RU-16117, also known as 11α-methoxy-17α-ethynylestradiol (11α-MeO-EE) or as 11α-methoxy-17α-ethynylestra-1,3,5(10)-triene-3,17β-diol, is a
syntheticestranesteroid and a
derivative of
estradiol.[1] It is specifically a derivative of
ethinylestradiol (17α-ethynylestradiol) with a
methoxy group at the C11α position.[1] The compound is the C11α
isomer or C11
epimer of
moxestrol (11β-methoxy-17α-ethynylestradiol).[1][9]
References
^
abcdefghijkRaynaud JP, Azadian-Boulanger G, Bouton MM, Colin MC, Faure N, Fernand-Proulx L, et al. (April 1984). "RU 16117, an orally active estriol-like weak estrogen". Journal of Steroid Biochemistry. 20 (4B): 981–993.
doi:
10.1016/0022-4731(84)90008-6.
PMID6427528.
^
abcdeRaynaud JP, Bonne C, Bouton MM, Moguilewsky M, Philibert D, Azadain-Boulanger (22 October 2013).
"Screening for anti-hormones by receptor studies". In James VH, Pasqualini JR (eds.). Proceedings of the Fourth International Congress on Hormonal Steroids: Mexico City, September 1974. Elsevier Science. pp. 618–621.
ISBN978-1-4831-4566-2.
^
abcRaynaud JP, Bouton MM, Moguilewsky M, Ojasoo T, Philibert D, Beck G, et al. (January 1980). "Steroid hormone receptors and pharmacology". Journal of Steroid Biochemistry. 12: 143–157.
doi:
10.1016/0022-4731(80)90264-2.
PMID7421203.
^
abBouton MM, Raynaud JP (August 1979). "The relevance of interaction kinetics in determining biological response to estrogens". Endocrinology. 105 (2): 509–515.
doi:
10.1210/endo-105-2-509.
PMID456327.
^Kelly PA, Asselin J, Caron MG, Raynaud JP, Labrie F (January 1977). "High inhibitory activity of a new antiestrogen, RU 16117 (11alpha-methoxy ethinyl estradiol), on the development of dimethylbenz(a)anthracene-induced mammary tumors". Cancer Research. 37 (1): 76–81.
PMID187338.
^Ojasoo T, Delettré J, Mornon JP, Turpin-VanDycke C, Raynaud JP (1987). "Towards the mapping of the progesterone and androgen receptors". Journal of Steroid Biochemistry. 27 (1–3): 255–269.
doi:
10.1016/0022-4731(87)90317-7.
PMID3695484.