Progesterone Receptor Antagonists

Antiprogestins are progesterone receptor antagonists such as mifepristone (RU 38486), ORG 31710, ZK137 316, ZK 230 211, ZK98299 (Onapristone). 

Rationale for the Use of Progesterone Receptor Antagonists in Cancer Treatment... 

Hoffmann J, Lichtner RB, Fuhrmann U, Michna H, Parczyk K, Neef G, Chwalisz K, Schneider MR (2002) Effects of Progesterone Receptor Antagonists on Breast Cancer. In Robertson JFR, Nicholson RI, Hayes DF (eds) Endocrine Management of Breast Cancer. Dunitz... 

U. Fuhrmann, H. Hess-Stumpp, A. Cleve, G. Neef, W. Schwede, J. Hoffmann, K.H. Fritzemeier, K. Chwalisz, Synthesis and biological activity of a novel, highly potent progesterone receptor antagonist, J. Med. Chem. 43 (2000) 5010-5016. 

Antiprogestine (ZK-230211) is a progesterone receptor antagonist developed for treatment of breast tumors. It is substimted at C-17 by a hydroxyl (17P) and a C2F5 group (17a), which is introduced with pentafluoroethyUithium, prepared in situ from pentafluoroethyl iodide and butyllithium (Figure 8.78). ... 

A very hard pre-contest appearance has been achieved by males when stacked with Oxandrolone and Halotestin if a estrogen/progesterone receptor antagonist ( See Nolvadex) had been utilized as well. As I said all purpose was commonly the term of choice. 

Figure 13.3. Stmctures of the gestagene steroid hormone progesterone, and the progesterone receptor antagonist mifepristone...

Competitive progesterone receptor antagonists are available, and one such, mifepristone, is used to procure therapeutic abortion see ABORTIFACIENTS. 

Progesterone receptor antagonists and their potential clinical applications (e.g. in uterine myoma, endometriosis, breast, ovarian or uterine cancer, or as potential contraceptives) are discussed by Irving M. Spitz. 

Nakagawa A, Uno S, Makishima M, Miyachi H, Hashimoto Y. Progesterone receptor antagonists with a 3-phenylquinazo-line-2,4-dione/2-phenylisoquinoline-l,3-dione skeleton. Bio-org. Med. Chem. 2008 16 7046-7054. 

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