作者:Miriam Penning、Jens Christoffers
DOI:10.1002/ejoc.201101645
日期:2012.3
Hexahydro-2-oxo-1,4-diazocin-6-carboxylic acid constitutes a conformationally rigid, crown-shaped scaffold. An orthogonally protected (Boc at N-4 and methyl ester at 6-CO2H) representative was prepared by ring expansion of a 3-pyrrolidone-derived 1,4-diketone with MeNH2. After deprotection, this building block was further diversified by reductive aminations and amidations and by sulfonamide and urea
Hexahydro-2-oxo-1,4-diazocin-6-carb 酸构成一个构象刚性的冠状支架。正交保护(N-4 处的 Boc 和 6-CO2H 处的甲酯)代表通过 3-吡咯烷酮衍生的 1,4-二酮与 MeNH2 的扩环来制备。脱保护后,该结构单元通过还原胺化和酰胺化以及磺酰胺和尿素的形成而进一步多样化。此外,在 BnOH 存在下,6-CO2H 官能团通过甲酰胺降解一步转化为 6-NHCbz 基团。环状三肽结构的一个例子是通过与 N-Boc-β-丙氨酸和甘氨酸甲酯酰胺化合成的。八元杂环的结构特征是通过 4-溴苯胺衍生物的单晶 X 射线结构分析建立的。