176254-10-7Relevant articles and documents
Preparation method of levonorgestrel pharmacopoeia impurity S
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Paragraph 0034-0040, (2020/12/14)
The invention belongs to the technical field of pharmacy, and particularly relates to a preparation method of a levonorgestrel pharmacopoeia impurity S. The preparation method comprises the followingsteps: carrying out a methyl etherification reaction on a compound 1, and carrying out an ethynylation reaction to obtain the levonorgestrel pharmacopoeia impurity S. The methyl etherification reaction comprises: dissolving the compound 1 in an organic solvent, adding trimethyl orthoformate, pyridine hydrochloride and methanol, and reacting to obtain a compound 2; and the ethynylation reaction comprises: dropwise adding the compound 2 dissolved in an organic solvent into an ethynylation reagent under the condition of -5 to 0 DEG C to react to obtain the levonorgestrel pharmacopeia impurity S.A preparation process of the ethynylation reagent comprises the step of introducing acetylene into an organic solvent containing butyl lithium to obtain the levonorgestrel pharmacopeia impurity S. Thesynthesis purity is high, the yield is high, and a basis is provided for a reference substance for quality control and analysis of the levonorgestrel and for control of generation of an impurity S insynthesis of the levonorgestrel.
