procedure has been developed for the preparation of the C-7 side chain of ceftobiprole, (Z)-2-(5-amino-1,2,4-thiadiazole-3-yl)-2-trityloxyiminoacetic acid (2) from malononitrile (9) in a total yield of 19%. The key intermediate N-(3-(2-acetamido-2-oxoethyl)-1,2,4-thiadiazol-5-yl)benzamide (15b) was synthesized for the first time in 76% yield by treatment of N-(3-aminoisoxazol-5-yl)acetamide (13) with benzoyl
已开发出一种新颖而有效的方法来制备头孢双丙,(Z)-2-(
5-氨基-1,2,4-噻二唑-3-基)-2-三苯氧基亚
氨基
乙酸的C-7侧链(2)来自
丙二腈(9),总产率为19%。通过处理N -(-),以76%的产率首次合成了关键中间体N-(3-(2-乙酰
氨基-2-氧代乙基)-
1,2,4-噻二唑-5-基)苯甲酰胺(15b)。
3-氨基异恶唑-5-基)乙酰胺(13)与
苯甲酰基异硫氰酸酯。更重要的是,由以下反应制备了(Z)-N-(3-(2-乙酰
氨基-2-氧代-1-(三苯氧基氧亚
氨基)乙基)-1,2,4-
噻二唑-5-基)苯甲酰胺(16b)。通过连续
肟化和保护
肟羟基,具有高立体选择性和良好收率的15b。该方法具有工业合成的良好前景。