Crystals of a vitamin D derivative and a method for the preparation thereof
AssigneeChugai Seiyaku Kabushiki Kaisha
InventorTsuyoshi Yamauchi
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Abstract
The present invention provides crystals of the compound represented by formula (I): crystals of a vitamin D derivative which are obtained by purifying a crude or preliminarily purified product of the vitamin D derivative through a reverse phase chromatography and then crystallizing the purified derivative from an organic solvent; novel compounds which are formed during the synthesis of a vitamin D derivative as by-product; and a method for purifying a vitamin D derivative or the precursor thereof. The method of the present invention makes it possible to supply a highly purified vitamin D derivative, especially ED-71, in bulk and steadily.
Claims5
A method for purifying the compound represented by formula (II):
- comprising recrystallizing a crude or preliminarily purified product of the compound represented by formula (II) from an alcohol.
A purified product of the compound represented by formula (II)
- which is obtained by recrystallizing a crude or preliminarily purified product of the compound represented by formula (II) from and alcohol.
A compound represented by formula (III):
- .
A compound represented by formula (IV):
- .
Dependencies are inferred from the claim text.