104286-02-4Relevant articles and documents
Method for preparing prednicarbate intermediate
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Paragraph 0025-0041, (2020/02/07)
The invention relates to a method for preparing a prednicarbate key intermediate (a compound of a formula III shown in the description). According to the method, a compound of a formula II shown in the description is adopted as a raw material, water and ethanol are adopted as solvents, and the compound of the formula III shown in the description is prepared through a hydrolysis reaction under theacid condition. Compared with the prior art, the conversion rate of the compound of the formula II shown in the description is increased, problems that the compound of the formula III shown in the description is not easy to separate, purify, crystallize and the like can be solved, the compound of the formula III with high purity can be conveniently and rapidly prepared, and the method is applicable to industrial production.
Investigation on the Photostability of Halometasone and Prednicarbate in the Crystal State and Crystal Structure of Halometasone
Reisch, Johannes,Henkel, Gerald,Ekiz-Guecer, Nurten,Nolte, Gerald
, p. 63 - 68 (2007/10/02)
UV irradiation of halometasone (1) in the crystal state yields three photoproducts: 2-chloro-6α,9-difluoro-11β,17α-dihydroxy-16-α-methyl-3-oxoandrosta-1,4-diene-17β-carbaldehyde (3), 2-chloro-6α,9-difluoro-11β-hydroxy-16α-methylandrosta-1,4-diene-3,17-dione (4) and the dimerization product 2ξ-chloro-2ξ-(2-chloro-6α,9-difluoro-11β,21ξ-trihydroxy-16α-methyl-3,20-dioxopregna-1,4-dien-21-yl)-6α,9-difluoro-11β,17,21-trihydroxy-16α-methylpregna-4-ene-3,20-dione (5).The structure of 5 is determined by the molecular packing of 1 in the crystal, as shown by an X-ray analysis of 1.Two photoproducts are formed after irradiation of prednicarbate (2): 11β,17-dihydroxy-21-propionyloxypregna-1,4-diene-3,20-dione (6) and 17-(ethoxycarbonyloxy)-11β,21-dihydroxypregna-1,4-diene-3,20-dione (7). Key Words: Prednicarbate / Halometasone / Photochemistry