The alkyne pathway to keramadine from the marine sponge Agelas sp.
作者:Thomas Lindel、Matthias Hochgürtel
DOI:10.1016/s0040-4039(98)00341-4
日期:1998.4
A novel synthesis of the pyrrole-imidazole alkaloid keramadine (1) from the marine sponge Agelas sp. is described. Regiocontrol is reached by the Pd-catalyzed alkynylation of 1-benzenesulfonyl-4-iodoimidazole, followed by N-methylation employing trimethyloxonium tetrafluoroborate. Key step is the double hydrogenation of a 5-alkynyl-2-azidoimidazole which simultanously generates the (Z)-double bond
从海洋海绵Agelas sp.1合成吡咯咪唑生物碱keramadine(1)。描述。通过Pd催化1-苯磺酰基-4-碘咪唑的炔基化反应,然后使用四氟硼酸三甲基氧鎓进行N-甲基化,可以实现区域控制。关键步骤是5-炔基-2-叠氮咪唑的双氢化反应,同时生成(Z)-双键和1的氨基官能团。