Method for the isolation of 6α, 9α-difluoro-11β, 17α-dihydroxy-16α-methylpregna-3-oxo-1,4-diene-17β-carboxylic acid
AssigneeChemagis Ltd.
InventorsYaacov Rubinsztain, Ariana Segal, Joseph Kaspi, Ori Lerman
Life of this patent
Estimating the term…
Abstract
The invention provides a process for the preparation and isolation of compound of formula 2, comprising the following steps: oxidizing Flumethasone dissolved in a tetrahydrofuran-water mixture with periodic acid at a temperature lower than 30° C.; cooling the reaction mixture to a temperature lower than 10° C.; adding an antisolvent precooled to a temperature lower than 10° C.; and separating the precipitated crystal by filtration, whereby there is obtained a compound of formula 2 in a yield of at least 98% and of a chromatographic purity of at least 99%.
Claims4
A process for the preparation and isolation of compound of formula 2, comprising the following steps:
- a. oxidizing Flumethasone dissolved in a tetrahydrofuran-water mixture with periodic acid at a temperature lower than 30° C.;
- b. cooling the reaction mixture to a temperature lower than 10° C.;
- c. adding an antisolvent precooled to a temperature lower than 10° C.;
- and
- d. separating the precipitated crystal by filtration,
- whereby there is obtained a compound of formula 2 in a yield of at least 98% and of a chromatographic purity of at least 99%.
Dependencies are inferred from the claim text.