- Preparation method of betamethasone dipropionate
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The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method of betamethasone dipropionate. According to the method, betamethason-17-propionate is taken as a raw material, propionic anhydride is taken as a raw material, under the condition that 4-dimethylaminopyridine is taken as a catalyst, betamethasone dipropionate is generated through reaction, and high-purity betamethasone dipropionate is obtained through refining by adopting absolute ethyl alcohol, dichloromethane and normal hexane. The preparation process is simple, the reaction temperature is moderate, and ultralow-temperature or high-temperature reaction is avoided; the solvent or reagent used in the preparation is cheap and easy to obtain, convenient to charge and easy to transport and store; the method has the advantages of small dosage of reaction catalyst, high yield, less generated waste liquid, environmental friendliness and suitability for commercial production.
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Paragraph 0009; 0044-0062
(2021/05/29)
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- Preparation method of betamethasone 17 alpha-propionate
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The invention provides a preparation method of betamethasone 17 alpha-propionate. According to the preparation method, betamethasone is subjected to a reaction with triethyl orthopropionate, the reaction is performed in a tetrahydrofuran solvent, further, p-toluenesulfonic acid is adopted as a catalyst, after the reaction is finished, an aluminum trichloride solution is dropwise added to the samesolvent system directly without discharging, a thermal insulation reaction is performed after the solution is dropwise added, and betamethasone 17 alpha-propionate is obtained with a post-treatment process. According to the preparation method of betamethasone 17 alpha-propionate, preparation process is simplified, yield is increased and purity is improved while the problem that dioxane, dimethylformamide or another solvent is adopted as the reaction solvent of betamethasone 17 alpha-propionate is solved.
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Paragraph 0011; 0012; 0013; 0014; 0015; 0016; 0018
(2019/08/20)
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- Pharmaceutical composition
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A pharmaceutical composition for dermal use, wherein the composition has a first pharmacologically active component A consisting of at least one vitamin D or vitamin D analogue, and a second pharmacologically active component B consisting of at least one corticosteroid, wherein the difference between the maximum stability pH of said first component A and the maximum stability pH of said second component B is at least 1. The composition can also have at least one solvent component C, where component C is compounds of the general formula R3(OCH2C(R1)H)xOR2(I), wherein x is in the range of 2-60, R1in each of the x units independently is H or CH3, R2is straight chain or branched C1-20alkyl or benzoyl, and R3is H or phenylcarbonyloxy; di-(straight or branched)-C4-10alkyl esters of C4-C8dicarboxylic acids; straight or branched C12-18-alkyl benzoates; straight or branched C2-4-alkyl esters of straight or branched C10-18-alkanoic or -alkenoic acids; propylenglycol diesters with C8-14-alkanoic acids; and branched primary C18-24alkanols.
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- Composition for the topical treatment of poison ivy and other forms of contact dermatitis
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Composition for topical administration comprising (a) a corticosteroid, and (b) a drying agent.
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