作者:Solène Guihéneuf、Ludovic Paquin、François Carreaux、Emilie Durieu、Laurent Meijer、Jean Pierre Bazureau
DOI:10.1039/c1ob06161e
日期:——
Dispacamide A and new analogs of this marine alkaloid were prepared in seven steps with an overall yield ranging from 12 to 33%. The key step of the strategy was a stereocontrolled Knoevenagel condensation under microwave dielectric heating in the last step. In this condensation, the 2-aminoimidazolin-4-one hydrochloride partners 10a–c were synthesized in three steps with good overall yields (33–79%) via the ring closure of N-guanidino acetic acids 9a–c and the aldehydes 5a,b as the two others building-blocks, in 3 steps with 60–66% overall yields. The six synthetic products have been obtained with a Z geometry about their exocyclic bond on the basis of 13C/1H long-range coupling constants using a gHSQMBC experiment.
Dispacamide A及其新类海洋生物碱的合成经过七个步骤,总体产率范围为12%至33%。该合成策略的关键步骤是在最后一步进行的受光谱控制的Knoevenagel缩合反应,采用微波介电加热。在这一缩合反应中,2-氨基咪唑啉-4-酮盐酸盐的反应物10a–c通过N-guanidino-乙酸9a–c的环合与醛5a,b作为另外两个构建块,经过三步合成,总体产率为良好的33%至79%。这六种合成产品在其外环键的Z几何构型是基于13C/1H长范围耦合常数,通过gHSQMBC实验获得的。