Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2005-01-11
2005-01-11
Badio, Barbara P. (Department: 1616)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
active
06841665
ABSTRACT:
A general, efficient, and environmentally friendly method is provided for producing mostly β-epoxides of Δ5-unsaturated steroids using certain ketones as the catalyst along with an oxidizing agent, or by using certain dioxiranes. In another aspect of the invention, a method is provided for producing mostly 5β,6β-epoxides of steroids from Δ5-unsaturated steroids having a substituent at the 3α-position by an epoxidation reaction using a ketone along with an oxidizing agent under conditions effective to generate epoxides, or using a dioxirane under conditions effective to generate epoxides. A whole range of Δ5-unsaturated steroids, bearing different functional groups such as hydroxy, carbonyl, acetyl or ketal group as well as different side chains, were conveniently converted to the corresponding synthetically and biologically interesting 5β,6β-epoxides with excellent β-selectivities and high yields.
REFERENCES:
patent: 3676433 (1972-07-01), Parikh
patent: 4613463 (1986-09-01), Sacks
patent: 5508452 (1996-04-01), Roussel et al.
patent: 5763623 (1998-06-01), Yang et al.
Bovicelli et al., “Oxidation of Natural Targets by Dioxiranes. Oxyfunctionalization of Steroids.” J. Org. Chem., vol. 57, pp. 2182-2184, 1992.*
Cicala et al., “Stereo- and Regioselectivities in the Epoxidation of Some Allylic alcohols by the Dioxirane Intermediate Generated in the Reaction of Potassium Caroate with Acetone.” J. Org. Chem., vol. 47, pp. 2670-2673, 1982.*
Holland et al., “1,3 Acyl Migration to an Epoxide. Reversible Rearrangement of 5,6 beta-Epoxyepicholesteryl Acetate.” J. Org. Chem., vol. 48, pp. 3134-3136, 1983.*
Yang et al., “Design of Efficient Ketone Catalysts for Epoxidation by Using the Field Effect.” J. Org. Chem., vol. 63, pp. 8952-8956, 1998.*
Collins, D., et al., “6α- and 6β-Acetic Acid Derivatives of Cholest-4-en-3-one and Pregn-4-ene-3, 20-dione,” Aust. J. Chem., vol. 29, pp. 2077-2085 (1976).
Kesavan, V., et al., “A Highly β-Stereoselective Catalytic Epoxidation of Δ5-Unstaturated Steriods with a Novel Ruthenium (II) Complex under Aerobic Conditions,” J. Org. Chem., vol. 63, pp. 6999-7001 (1998).
Marchon, J., et al., “Stereospecific Epoxidation by Air of Cholest-5-ene Derivatives catalysed by a Ruthenium Porphyrin,” J. Chem. Soc., Chem. Commun, pp. 298-299 (1988).
Marchon, J., et al., “A Convenient Systhesis of 5,6β-Epoxides of Some Cholesteryl Esters and Δ5-Ketosteroid Derivatives by Catalytic β-Stereoselective Epoxidation,” Communications, pp. 389-391 (1989).
Marples, B., et al., “Dioxirane Mediated Steroidal Alkene Epoxidations and Oxygen Insertion into Carbon-Hydrogen Bonds,” Tetrahedron Letters, vol. 32, No. 4, pp. 533-536 (1991).
Parish, E., et al., “A One-Step Synthesis of 6β-Hydroxy-Δ 4-3-Ketones. Novel Oxidation of Homoallyic Sterols with Permanganate Ion,” J. Org. Chem., vol. 61, pp. 5665-5666 (1996).
Salvador, J., et al., “Oxidations with Potassium Permanganate-Metal Sulphates and Nitrates. β-Selective Epoxidation of 5Δ-Unsaturated Steroids,” Tetrahedron Letters, vol. 37, No. 5, pp. 687-690 (1996).
Symala, M., et al., “A Novel and Highly β-Selective Epoxidation of Δ5-Unstaturated Steroids with Permanganate Ion,” J. Org. Chem., vol. 57, pp. 1928-1930 (1992).
Yang D., et al., “Epoxidation of Olefins Using Methyl(trifluoromethyl)dioxirane Generated in Situ,” J. Org. Chem., vol. 60, pp. 3887-3889 (1995).
Yang D., et al., “Novel Cyclic Ketones for Catalytic Oxidation Reactions,” J. Org. Chem., vol. 63, pp. 9888-9894 (1998).
Yates, P., et al., “Studies of the Synthesis of 5-Hydroxy 6-Keto Steroids and Related 6-Keto Steroids,” Can. J. Chem., vol. 65, pp. 2203-2216 (1987).
Yang, D., et al., “Highly β-Selective Epoxidation of Δ5-Unsaturated Steroids Catalyzed by Ketones,” Chem. Eur. J., vol. 6, No. 19, pp. 3517-3521 (2000).
Yang X. et al.,Biochemistry, 2000, vol. 39, pp. 4915-4923.
Yang, D., et al., “Diastereoselective Epoxidation of Cyclohexene Derivatives by Dioxiranes Generated in Situ. Importance of Steric and Field Effects,” J. Org. Chem., vol. 64, pp. 1635-1639 (1999).
Jiao Guan-Sheng
Yang Dan
Badio Barbara P.
Jones Day
The University of Hong Kong
LandOfFree
Method for synthesizing 5β, 6β-epoxides of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for synthesizing 5β, 6β-epoxides of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for synthesizing 5β, 6β-epoxides of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3390263