An effective method for (R)-1-hydroxyethylation of benzyl bis(phenylseleno)penicillanate is described. The hydroxyethylated product was transformed into the 4-methylsulfonyl- and 4-phenylsulfonyl-2-azetidinone derivatives. These monocyclic compounds were reacted with potassium cyanide under two-phase conditions to give the 4-cyano-2-azetidinone derivative (C1-unit introduction) in high yield. The cyano group was then converted into the iodomethyl group. Using the 4-iodomethyl-2-azetidinone derivative an isopenam derivative was synthesized. Furthermore, carbapenam derivative were also constructed by a novel [3+2] cyclization reaction between 4-iodomethyl-2-azetidinone and dimethyl 2-methylthio- and 2-phenylthiofumarate.
本研究描述了一种有效的方法,用于(R)-1-羟乙基化双(苯基
硒)青霉烷酸苄酯。羟乙基化产物转化为 4-甲磺酰基和 4-苯磺酰基-
2-氮杂环丁酮衍
生物。在两相条件下,这些单环化合物与
氰化钾反应,得到高产率的 4-
氰基-
2-氮杂环丁酮衍
生物(C1-单位引入)。
氰基随后转化为
碘甲基。利用 4-
碘甲基-
2-氮杂环丁酮衍
生物合成了异培南衍
生物。此外,通过 4-iodomethyl-2-azetidinone 与 2-甲
硫基和 2-苯
硫基
富马酸二甲酯之间的新型 [3+2] 环化反应,还合成了碳青霉烯类衍
生物。