- Epoxidation of 1,4-dienyl 3-keto steroidal compounds by dimethyldioxirane: Kinetics
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The epoxidation of 1,4-dienyl 3-keto steroidal compounds by dimethyldioxirane yields mono-epoxides as the primary products as reported in the literature. Kinetic data show the 1,4-dienyl 3-keto system to be at least ten fold more reactive than simple α,β-
- Navarro-Eisenstein, Angela M.,Vasquez, Pedro C.,Franklin, Paul J.,Baumstark
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- o-Iodoxybenzoic acid in dimethylformamide as a convenient reagent for the oxidation of alcohols to aldehydes and ketones
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DMF dissolves o-iodoxybenzoic acid (up to 0.1 mol dm-3) and, therefore, is a solvent of choice for the reactions with o-iodoxybenzoic acid simplifying significantly a product isolation procedure due to a higher volatility. The reaction rate and selectivity of the oxidation of alcohols to corresponding carbonyl compounds with o-iodoxybenzoic acid in DMF are close to those in DMSO.
- Lapitskaya, Margarita A.,Vasiljeva, Ljudmila L.,Pivnitsky, Kasimir K.
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- 9-site dehalogenation preparation method of 9-halogenated steroid hormone compound
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The invention discloses a 9-site dehalogenation method of a steroid hormone compound. The method comprises the following steps of: dissolving a 9-halogenated-11-hydroxy steroid compound or a 9-halogenated-11-hydroxy ester steroid compound into an organic solvent; heating to a certain temperature, slowly adding a proper amount of a dehalogenation reagent, carrying out a reaction for a period of time, carrying out detection, carrying out reduced pressure concentration to remove a part of the solvent after the reaction is completed, carrying out cooling crystallization or crystallization by adding water, separating out a solid, and filtering to obtain the target product that is a 11-carbonyl steroid compound or a 11-hydroxy ester steroid compound. The method has the advantages of simple operation, few reaction impurities, high yield, capability of avoiding of the use of a metal dehalogenation agent and mercaptofatty acid, reduction of three-waste pollution, and suitableness for industrialproduction.
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Paragraph 0029-0031
(2020/07/15)
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- Preparation method of prednisone
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The invention discloses a preparation method of prednisone, and belongs to the technical field of preparation and processing of medicines. According to the method, hydrocortisone acetate is used as aninitial raw material, and the prednisone is prepared through three steps of oxidation, biological fermentation dehydrogenation and hydrolysis. According to the preparation method of prednisone, the defects of a traditional process are overcome, the target product is high in purity, good in quality stability, high in yield, low in production cost and mild in reaction condition, a highly toxic cyanide reagent is prevented from being used, and the method is easy and convenient to operate, suitable for industrial production and wide in market prospect.
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- A by the 3,17-dione steroid preparing steroid the synthetic method of the compound of
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The invention discloses a synthetic method of steroid type drugs and intermediates, in particular relates to a synthetic method for preparing 17-hydroxy-20-ketone steroid compounds from 3,17-diketone steroids, and belongs to the field of synthesis of drugs. The method takes 3,17-diketone steroids as raw materials and adopts a conventional, environment-friendly, low-toxicity reagent, and the steroid type drugs such as cortisone, hydrocortisone, metacortandracin, or hydroprednisone, or intermediates 17alpha-hydroxy-20-ketone compounds are prepared simply and conveniently at high yield by selective protection of C3 or (and) C11-ketone group, Wittig reaction of C17, selective oxidization of 17(20)-position double bonds and halogenating replacement. The aftertreatment is simple, few three wastes are generated, the reaction selectivity is good, the yield is high, and byproducts anti-pregnancy steroidal drugs and steroidal compounds can be obtained. The raw materials are easy to get, the cost is low and the synthetic process is simple; the synthetic method is suitable for industrial production.
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Paragraph 0102; 0103; 0148-0153
(2017/03/14)
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- Pyridinium o-iodoxybenzoate as a safe form of a famous oxidant
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The stable pyridinium salt of o-iodoxybenzoic acid (PIBX) that is easy to obtain can serve as a convenient substitute of IBX as an oxidant. PIBX is safer, has neutral properties behaves as an equivalent to IBX in the oxidation of alcohols to ketones or aldehydes in polar solvents (DMF, DMSO), and provides higher oxidation rate in THF due to better solubility.
- Kumanyaev, Ivan M.,Lapitskaya, Margarita A.,Vasiljeva, Ljudmila L.,Pivnitsky, Kasimir K.
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experimental part
p. 129 - 131
(2012/09/05)
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- Radiolytic degradation scheme for 60Co-irradiated corticosteroids
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The cobalt 60 radiolytic degradation products have been identified in the following corticosteroids: cortisone, cortisone acetate, hydrocortisone, hydrocortisone acetate, hydrocortisone sodium succinate, isoflupredone acetate, methylprednisolone, methylprednisolone acetate, prednisolone, prednisolone acetate, and prednisone. Two major types of degradation processes have been identified: loss of the corticoid side chain the D-ring to produce the C-17 ketone and conversion of the C-11 alcohol, if present, to the C-11 ketone. Minor degradation products derived from other changes affecting the side chain are also identified in several corticosteroids. These compounds are frequently associated in corticosteroids as process impurities or degradation compounds. No new radiolytic compounds unique to 60Co-irradiation have been found. The majority of corticosteroids have been shown to be stable to 60Co-irradiation. The rates of radiolytic degradation ranged from 0.2 to 1.4%/Mrad.
- Kane,Tsuji
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