Synthesis of an analogue of lavendamycin and of conformationally restricted derivatives by cyclization via a hemiaminal intermediate
作者:Arnaud Nourry、Stéphanie Legoupy、François Huet
DOI:10.1016/j.tetlet.2007.06.100
日期:2007.8
Quinoline 12 was obtained by a Friedländer reaction from 2-aminobenzaldehyde and methyl acetoacetate. Reduction, silylation then oxidation provided compound 8a. A Pictet–Spengler reaction between the latter and tryptophan methyl ester yielded compound 14, then compound 7 by desilylation. Numerous attempts to prepare a cyclized derivative of this analogue of lavendamycin 7 by conventional ways failed
通过Friedländer反应从2-氨基苯甲醛和乙酰乙酸甲酯获得喹啉12。还原,甲硅烷基化然后氧化,得到化合物8a。后者与色氨酸甲酯之间发生Pictet-Spengler反应,生成化合物14,然后通过去甲硅烷基化反应生成化合物7。通过常规方法制备拉维达霉素7类似物的环化衍生物的许多尝试均以失败告终。幸运的是,通过半胱氨酸中间体获得了良好的结果,因此以令人满意的产率获得了化合物21。在其还原过程中发生了共轭加成,导致化合物22。用化合物7和构象受限的类似物21和22进行了生物学测试。