.alpha.-Aminoacylpenicillin antibiotics such as ampicillin and amoxycillin may be prepared in particularly simple manner by a process which comprises preparing a solution of 6-aminopenicillanic acid (6-APA) in a water-immiscible organic solvent by treating 6-APA with an excess of a strong tertiary amine base in the presence of said solvent; neutralising the residual strong tertiary amine base in said solution; reacting the neutralised solution with a solution in a water-immiscible organic solvent of an acylating agent which is a mixed anhydride of a lower alkoxyformic acid and an N-protected derivative of an .alpha.-aminoacid wherein the N-protecting group is acid-labile, to yield a solution of an N-protected .alpha.-aminoacylpenicillin derivative; contacting the resulting solution with water and a strong acid to cleave the acid-labile N-protecting group; and isolating the thus-obtained .alpha.-aminoacylpenicillin from the resulting water-containing system. The use of water-immiscible solvents in the process obviates the need for a solvent evaporation stage during isolation of the .alpha.-aminoacylpenicillin product and thus renders the process of particular advantage in plant-scale operations.
.alpha.-
氨基酰
青霉素类抗生素,如
氨苄
青霉素和
阿莫西林,可以通过以下简单的方法制备:首先将
6-氨基青霉烷酸(6-APA)与过量的强三级胺碱在不溶于
水的有机溶剂中反应,以制备6-APA的溶液;然后中和溶液中残留的强三级胺碱;接着将中和后的溶液与不溶于
水的有机溶剂中的酰化试剂反应,该酰化试剂是较低的烷氧基
甲酸和一种
α-氨基酸的N-保护衍
生物的混合酸酐,其中N-保护基为酸敏感,以产生一种N-保护的α-
氨基酰
青霉素衍
生物的溶液;然后将所得溶液与
水和强酸接触,以裂解酸敏感的N-保护基;最后从所得含
水体系中分离出α-
氨基酰
青霉素。该过程中使用的不溶于
水的溶剂消除了α-
氨基酰
青霉素产品的分离过程中需要蒸发溶剂的需求,因此在工厂规模的操作中具有特殊优势。