- C21 steroid 21 site acetylation process
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The invention discloses a C21 steroid 21 site acetylation process. C21 steroid is prednisolone, hydrocortisone, dexamethasone or betamethasone; the C21 steroid is subjected to acetylation with aceticanhydride; the acetylation of the C21 steroid with the acetic anhydride is carried out in a mixed solvent; an acetic acid alkali metal salt is adopted as a catalyst, and the reaction is carried out inthe presence of an inert gas; the mixed solvent is a mixed solvent of tetrahydrofuran and acetone; the weight ratio of the tetrahydrofuran to the acetone in the mixed solvent is (2-9):1. High-toxicity and high ammonia nitrogen pyridine and dimethylformamide are replaced by using the mixed solvent of tetrahydrofuran and acetone without ammonia nitrogen, no high ammonia nitrogen wastewater is generated, and environment pollution can be reduced.
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Paragraph 0022-0024
(2018/11/22)
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- Ring opening and fluoridation method and device of steroidal epoxy compound
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The invention discloses a method of preparing a compound II, which is as shown as the following reaction formula as shown in the specification. A 9 alpha-fluorine-11 beta -hydroxyl steroidal compound II is prepared via epoxy compound ring opening and fluoridation of a steroidal epoxy compound I by taking hydrogen fluoride as a fluorination reagent in a solvent consisting of arene and water. In the formula, R is CH3, CH2OH or CH2OAc; R1 is OH; R2 is alpha-CH3 or beta-CH3; and R3 is F or H. A continuous reaction device as shown in Figure 1 can be used in the method.
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Paragraph 0038; 0039; 0041
(2017/07/22)
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- Preparation technology for dexamethasone sodium phosphate
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The invention relates to a preparation technology for dexamethasone sodium phosphate. The preparation technology comprises the following steps: a ring-opening reaction is carried out, namely, dexamethasone acetate epoxide is employed as an initial raw material, HF and DMF are added, a reaction is performed for 3h, a ring-opening reaction is carried out and a dexamethasone acetate solution is prepared; recrystallization is carried out, namely, acetone or ether is added in the dexamethasone acetate solution, recrystallization is carried out, dexamethasone acetate is prepared, and rotary distillation is employed to remove the solvent after recrystallization; base catalysis hydrolysis is carried out, namely, dexamethasone acetate is added in Na2CO3 and methanol, a reaction is carried out for 10min, dexamethasone is prepared; pyrophosphoryl chlorine esterification is carried out, namely, dexamethasone is reacted with pyrophosphoryl chlorine and THF, and dexamethasone phosphate ester is prepared; a neutralization salt forming reaction is carried out, namely, the dexamethasone phosphate ester obtained from the fourth step is reacted with NaOH and methanol, and dexamethasone sodium phosphate is prepared. The steps are simple, raw materials are easily available, the reaction conditions are mild, the preparation technology is suitable for industrial production, and the cost is low.
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Paragraph 0014
(2016/10/08)
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- Preparation method for dexamethasone sodium phosphate
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The invention relates to a preparation method for dexamethasone sodium phosphate. The preparation method comprises the following steps: a ring-opening reaction is carried out, namely, dexamethasone acetate epoxide is employed as an initial raw material, HF and DMF are added, a reaction is performed for 3h, a ring-opening reaction is carried out and a dexamethasone acetate solution is prepared; recrystallization is carried out, namely, methanol is added in the dexamethasone acetate solution, recrystallization is carried out, and dexamethasone acetate is prepared; base catalysis hydrolysis is carried out, namely, dexamethasone acetate is added in Na2CO3 and methanol, a reaction is carried out for 10min, dexamethasone is prepared; pyrophosphoryl chlorine esterification is carried out, namely, dexamethasone prepared in the third step is reacted with pyrophosphoryl chlorine and THF, and dexamethasone phosphate ester is prepared; a neutralization salt forming reaction is carried out, namely, the dexamethasone phosphate ester obtainedin the fourth step is reacted with NaOH and methanol at a reaction temperature of 20 DEG C-30 DEG C for 1h, and dexamethasone sodium phosphate is prepared. The steps are simple, raw materials are easily available, the reaction conditions are mild, the method is suitable for industrial production, and the cost is low.
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Paragraph 0014
(2016/11/09)
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- 16α-methylation process
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Disclosed is a process for the production of a Δ17(20) -steroid of the formula STR1 which comprises starting with a 16-unsaturated corticoid of the formula STR2 and contacting the 16-unsaturated corticoid (I) with a methylating agent in the presence of a copper catalyst and a silylating agent.
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- α-Keto Mesylate: A Reactive, Thiol-Specific Functional Group
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A systematic study of the reactivity of α-keto mesylates with various nucleophiles (i.e., carboxylate, -OH, imidazole, -NH2, thiol acid anion, and -SH) under mildly basic conditions is reported. α-Keto mesylates do not react with imidazole or hydroxyl groups, react extremely slowly (if at all) with carboxylate and primary amines, and react several thousand times faster with thiols and thiol acid anions.The very rapid reaction with thiols occurs only with the dissociated thiolate anion.The addition of a β-hydroxyl group to α-keto mesylates accelerates the reaction with thiolate anions by a factor of 3-12 in acetone but has no effect on reactions run in dimethylformamide. α-Keto mesylates exhibit the same selectivity for thiolate anions, as compared to amines, as do α-keto chlorides.In view of this reactivity and selectivity, the α-keto mesylate appears to be a promising functional group for the electrophilic affinity labeling of biological macromolecules in weakly basic solutions.
- Simons, Stoney S.,Pons, Michel,Johnson, David F.
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p. 3084 - 3088
(2007/10/02)
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