76855-69-1Relevant articles and documents
Preparation method of 4AA
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Paragraph 0016; 0018; 0020-0021; 0023-0024; 0026, (2021/07/28)
The invention discloses a preparation method of 4AA. The preparation method comprises the following steps: S1, preparing a first intermediate from benzamide and a formaldehyde aqueous solution; S2, preparing a second intermediate from the first intermediate, thionyl chloride, toluene and n-heptane; S3, preparing a third intermediate from the second intermediate, methyl acetoacetate, sodium methoxide, toluene, diluted hydrochloric acid and isopropanol; S4, preparing a fourth intermediate from the third intermediate, reductase, ethyl acetate, saturated sodium bicarbonate and saturated salt water; S5, preparing a fifth intermediate from the fourth intermediate, imidazole, TBSCL and methylbenzene; S6, preparing a sixth intermediate from the fifth intermediate, ethanolamine, methanol and n-heptane; S7, preparing a seventh intermediate by using the sixth intermediate, a Grignard reagent and n-heptane; and S8, preparing 4AA from the seventh intermediate, ruthenium trichloride, potassium acetate, ethyl acetate, acetic acid and a peracetic acid solution.
Preparation method of azetidinone compound and preparation method 4 - acyloxy-azetidinone compound
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Paragraph 0101; 0103; 0104, (2021/11/19)
The invention provides a preparation method of a azetidinone compound and a preparation method of 4 - acyloxy-azetidinone compound. The preparation method comprises the following steps S1, an epoxy amide compound reacts with I alkali reagents to form a ring reaction, and first 1st reaction systems are obtained. Step S2: The first reaction system is subjected to hydroxyl protection reaction with a raw material including a silanization reagent and a nitrogen-containing basic organic matter to obtain second reaction systems. In step S3, second reaction system and second base reagent are subjected to isomerization reaction to obtain the azetidinone compound, wherein the epoxy amide compound has the structure shown VI, the separation process of the isomer product of the structure shown II and formula III IV is avoided, and the selectivity and yield of the azetidinone compound are improved.
Synthetic method of penem drug intermediate
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, (2020/05/19)
The invention discloses a method for synthesizing biapenem medicine intermediates. The method has the advantages that the biapenem medicine intermediates 4-AA are prepared from (R)-3-polyhydroxybutyrate which is a raw material, and the raw material in the routes is inexpensive, is easily available and can be substantially purchased; the method includes simple steps, the various steps are high in yield, and reaction is simple; chiral reagents and chiral resolution are omitted, accordingly, the method is low in cost and high in yield, and reaction conditions are easily available.