- Synthesis of [3α-3H] 17α-Hydroxy pregnenolone and [3α-3H] Pregnenolone
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For the first time, [3α-3H] 17α-hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β-3H] isomer in RP-HPLC purified product was identified by tritium NMR. The [3β-3H] isomer was then separated from [3α-3H] 17α-hydroxy pregnenolone with chiralPAK AD-H column. [3α-3H] pregnenolone (2) was synthesized from commercial available 5-pregnen-3,20-dione in one step with an improved procedure. [3α-3H] 17α-hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β- 3H] isomer was identified then separated with chiralPAK AD-H column. [3α-3H] pregnenolone (2) was synthesized from commercial available 5-pregnen-3,20-dione in one step. Copyright
- Tian, Yuan,Hong, Yang,Bonacorsi, Samuel J.,Balog, Aaron,Gong, Sharon
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- Preparation method of 6-methylene-17alpha-hydroxyprogesterone acetate
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The invention discloses a preparation method of 6-methylene-17alpha-hydroxyprogesterone acetate. The preparation method comprises the following steps: (1) enabling 17alpha-hydroxyl progesterone to have acylation reaction with 0.025 to 0.1 time of amount of substance of catalyst and 1 to 10 times of amount of substance of acetic anhydride, then adding 1 to 1.5 times of amount of substance of Mannich reagent into 2 to 10 times of mass ratio of solvent to have reaction, wherein the reaction temperature is -10 DEG C to 60 DEG C, the reaction time is 3 to 10 hours, and obtaining 6-methylene-17alpha-hydroxyprogesterone acetate tertiary amine; and (2) enabling the 6-methylene-17alpha-hydroxyprogesterone acetate tertiary amine to have reaction with 1 to 10 times of amount of substance of acid, wherein the reaction temperature is -10 DEG C to 70 DEG C, the reaction time is 1 to 5 hours, thus obtaining the product 6-methylene-17alpha-hydroxyprogesterone acetate. By adopting the preparation method, medroxyprogesterone and megestrol acetate progestational hormone can be conveniently prepared. The preparation method has the characteristics of good quality, high yield and easiness in industrialization, and has important significance on preparing sterides drugs.
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Paragraph 0026-0027; 0030-0031; 0034-0035; 0038-0039
(2017/08/29)
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- Microwave induced selective enolization of steroidal ketones and efficient acetylation of sterols in semisolid state
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Under microwave irradiation steroidal enones, more specifically, position three carbonyls were efficiently and selectively converted to the corresponding enol acetates in the presence of additional enolizable carbonyl functions at other positions, using acetic anhydride and a catalytic amount of toluene-p-sulfonic acid. Acetylation of hydroxyl groups of the sterols, including those at the hindered positions, was near quantitative. Strictly anhydrous conditions were not a pre-requisite for acetylation and the reaction system easily tolerated up to 10% (v/v) moisture.
- Marwah, Padma,Marwah, Ashok,Lardy, Henry A.
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p. 2273 - 2287
(2007/10/03)
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- 15β-Hydroxysteroids (part V). Steroids of the human perinatal period: The synthesis of 3β, 15β, 17α-trihydroxy-5-pregnen-20- one from 15β, 17α-dihydroxy-4-pregnen-3,20-dione
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A simple three-step synthetic method is reported on the conversion of Δ4-3-ketosteroids to the corresponding 3β- hydroxy-Δ5-steroid analogues. 17α-Hydroxy-4-pregnen-3,20-dione (10a) was used as a model to develop a method for the synthesis of 3β,17α-dihydroxy-5-pregnen-20-one (16). The major problem being the synthesis of 3,17α-diacetoxy-3,5-pregnadien-20-one (14) was solved by acetylating using a mixture of acetic anhydride and perchloric acid. The conversion of 15β,17α-dihydroxy-4-pregnen- 3,20-dione (8), product of Penicillium citrinum fermentation, to the desired 3β, 15β, 17α-trihydroxy-5-pregnen-20-one (1), is described using a modification of this method. Reaction of 8 with acetic anhydride and perchloric acid in ethyl acetate gave 3,15β,17α-triacetoxy-3,5-pregnadien-20-one (17) which on reduction with sodium borohydrice gave 5-pregnen-3β,15β,17α, 20(S + R)-tetrols (18a and 18b); however, reduction of 17 with a mixture of sodium borohydride and potassium bicarbonate gave after basic hydrolysis with metanolic sodium hydroxide the desired product 3β,15β,17α-trihydroxy-5-pregnen-20-one (1) in good yield (54%).
- Joannou,Reeder
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- Site-Selective Fluorination of Organic Compounds Using 1-Alkyl-4-fluoro-1,4-diazabicyclooctane Salts (Selectfluor Reagents)
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The new "N-F"-type electrophilic reagent family of 1-alkyl-4-fluoro-1,4-diazabicyclooctane salts (derived from elemental fluorine (F2) and 1-alkyl-1,4-diazabicyclooctane salts) has been found to be very effective for the fluorination of a wide variety of organic substrates.These include steroidal enol acetates and silyl enol ethers, phenyl-substituted olefins, sulfides bearing α-H atoms, certain carbanions, and mildly activated aromatic compounds.The products were obtained with good yields and regioselectivity under very mild reaction conditions.
- Lal, G. Sankar
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p. 2791 - 2796
(2007/10/02)
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