High-yield amination and cyclization of the chloride 15 to the pyrrolidin-2-one 16 was accomplished by a simple treatment with ammonia. Thiation of 16 and the Birch reduction of the resultant thiolactam 18 provided the C-2 side chain 2 in high yield with the asymmetric center retained as such. The side chain 2 was installed into the 1-beta-methylcarbapenem skeleton either by coupling with the vinyl phosphate
描述了一种新型的口服活性1-β-甲基卡巴培南TA-949(1)的简便经济合成方法。关键过程涉及从
L-天冬氨酸有效合成C-2侧链(R)-4-巯基
吡咯烷-2-
硫酮2和1-β-甲基卡巴培南骨架的构建。通过将
L-天冬氨酸β-甲基酯盐酸盐12的
氨基脱
氨基溴化,然后用苯
甲硫醇钾进行完全S(N)2型取代,形成具有R-构型的2巯基。通过用
氨进行简单处理,可以将
氯化物15高产率地胺化和环化为
吡咯烷酮-2-酮16。16的
硫杂化和所得
硫代内酰胺18的桦木还原提供了高收率的C-2侧链2,并保留了不对称中心。