To prepare the compound (1'R, 3S)-3-(1'-tri-substituted silyloxyethyl) azetidin-2-one, (2S, 3R)-2-aminomethyl-3-hydroxybutyric acid is reacted with an alcohol in the presence of at least one compound chosen from the group consisting of thionyl chloride, hydrogen chloride and p-toluene sulfonic acid, thereby obtaining a salt of the corresponding ester. The salt is reacted with a tri-substituted silane in the presence of a metallic catalyst, thereby protecting the hydroxy group of the ester and then reacted with a base, thereby obtaining an ester of (2S, 3R)-2-aminomethyl-3-(tri-substituted silyloxy) butyric acid. Subsequently, the ester is transformed into lactam in the presence of a Grignard reagent or a metal amide, thereby obtaining (1'R,3S)-3-(1'-tri-substituted silyloxyethyl)azetidin-2-one. This compound provides a useful base for preparing β-lactam type antimicrobial agents such as carbapenem type agents.
为了制备化合物(1'R, 3S)-3-(1'-三取代
硅氧基乙基)氮杂
环丁烷-2-酮,(2S, 3R)-2-
氨基甲基-3-羟基
丁酸在至少一种选自
硫酰氯、
氯化氢和
对甲苯磺酸的化合物的存在下与醇反应,从而得到相应酯的盐。该盐在
金属催化剂存在下与三取代
硅烷反应,从而保护酯的羟基,然后与碱反应,得到 (2S,3R)-2-
氨甲基-3-(三取代
硅氧基)
丁酸酯。随后,在
格氏试剂或
金属酰胺的存在下,酯转化为内酰胺,从而得到 (1'R,3S)-3-(1'-三取代
硅氧基乙基)氮杂
环丁烷-2-酮。这种化合物为制备 β-内酰胺类抗菌剂(如碳青霉烯类制剂)提供了有用的基础。