Title: Melengestrol Acetate
CAS Registry Number: 2919-66-6
CAS Name: 17-(Acetyloxy)-6-methyl-16-methylenepregna-4,6-diene-3,20-dione
Synonyms: 6a-methyl-6-dehydro-16-methylene-17-acetoxyprogesterone
Trademarks: MGA (Pharmacia & Upjohn)
Molecular Formula: C25H32O4
Molecular Weight: 396.52
Percent Composition: C 75.73%, H 8.13%, O 16.14%
Literature References: Orally active progestational steroid. Prepn: D. N. Kirk
et al., GB 886619;
eidem,
US 3332940 (1962, 1967 both to British Drug Houses). Environmental degradation study: B. Schiffer
et al., Environ. Health Perspect. 109, 1145 (2001). Receptor binding study: G. A. Perry
et al., Domest. Anim. Endocrinol. 28, 147 (2005). Review of pharmacology in animals: R. G. Zimbelman
et al., J. Am. Vet. Med. Assoc. 157, 1528-1536 (1970); of use in control of bovine estrus: D. J. Patterson
et al., J. Anim. Sci. 67, 1895-1906 (1989).
Properties: Needles from acetone/hexane, mp 224-226°. [a]D23 -127° (c = 0.31 in chloroform). uv max (ethanol): 287.5 nm (log e 4.35). LD50 (mg/kg): >8000 orally in rats; >2500 i.p. in mice (Zimbelman).
Melting point: mp 224-226°
Optical Rotation: [a]D23 -127° (c = 0.31 in chloroform)
Absorption maximum: uv max (ethanol): 287.5 nm (log e 4.35)
Toxicity data: LD50 (mg/kg): >8000 orally in rats; >2500 i.p. in mice (Zimbelman)
Therap-Cat-Vet: Progestogen; growth promotant.
