Carbon skeleton of polysubstituted pyroglutamates with three contiguous asymmetric centers was built up in one base-induced coupling/cyclization reaction of α-sulfonylacetamide with 2-bromo-2-propenoates. A simple transformation to 3-substituted prolinols can be easily achieved via reduction and desulfonation. A ring expansion of prolinol has been used as the key step in the formal synthesis of isoguvacine and paroxetine. The one-pot conversion of 3-substituted prolinol to the 3-substituted pyroglutamic acid is also reported.
在一次α-磺酰基乙酰胺与2-
溴-2-
丙烯酸酯的碱诱导偶联/环化反应中,构建了含有三个连续不对称中心的取代焦谷
氨酸盐的碳骨架。通过还原和脱磺化,可以轻松实现向3-取代的脯
氨醇的简单转化。脯
氨醇的环扩张已被用作异古瓦辛和
帕罗西汀的形式合成的关键步骤。还报道了3-取代脯
氨醇向3-取代焦谷
氨酸的一锅法转化。