Patent ID: 8324412
Filing Date: 2012-12-04
Classification: A61P,C07J,Y10T

Abstract:
1. A method for preparing asoprisnil on a pilot or manufacturing scale, by reacting as follows 17β-Hydroxyestra-4,9-dien-3-one (hydroxyestradienone) 3,3-Dimethoxyestra-5(10),9(11)-diene-17-one (nordienedione ketal) 3,3,17β-Trimethoxy-17α-methoxymethylestra-5(10),9(11)-diene (trimethoxydiene) 4-[17β-Methoxy-17α(methoxymethyl)-3-oxoestra-4,9-dien- 11β-yl]-benzaldehyde (dienone aldehyde) 11β- [4-(Hydroxyiminomethyl)-phenyl-17β-methoxy-17α-methoxymethyl-estra4,9-dien-3-one (asoprisnil) by oxidation of 17β-hydroxyestra-4,9-dien-3-one (hydroxyestradienone) to estra-4,9-diene-3,17-dione (nordienedione) and subsequent selective ketalization to 3,3 dimethoxyestra-5(10),9(11)-diene-17-one (nordienedione ketal) or by ketalization of hydroxyestradienone to 17β-hydroxy-3,3-dimethoxyestra-5(10),9(11)-diene (hydroxy ketal) and subsequent oxidation to nordienedione ketal,