LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal.
Molecules. 2020 Feb 12;25(4):797. doi: 10.3390/molecules25040797.
The synthesis of an unreported 2-aminopyrrolidine-1-carboxamidine unit is here described for the first time. This unusual and promising structure was attained through the oxidative decarboxylation of amino acids using the pair of reagents, silver(I)/peroxydisulfate (Ag(I)/SO) followed by intermolecular (in the case of l-proline derivative) and intramolecular trapping (in the case of acyl l-arginine) by -nucleophiles. The l-proline approach has a broader scope for the synthesis of 2-aminopyrrolidine-1-carboxamidine derivatives, whereas the intramolecular cyclization afforded by the l-acylarginines, when applied, results in higher yields. The former allowed the first synthesis of cernumidine, a natural alkaloid isolated in 2011 from Vell, as its racemic form.
本文首次描述了一种未报道的 2-氨基吡咯烷-1-甲脒基单元的合成方法。该不寻常且有前景的结构是通过使用银（I）/过二硫酸盐（Ag（I）/SO）试剂对氨基酸进行氧化脱羧反应而得到的，然后通过 -亲核试剂进行分子间（脯氨酸衍生物的情况）和分子内（酰基精氨酸的情况）捕获。对于 2-氨基吡咯烷-1-甲脒衍生物的合成，l-脯氨酸方法具有更广泛的适用范围，而通过 l-酰基精氨酸进行的分子内环化，如果适用，会产生更高的收率。前者使得首次以其外消旋形式合成了 2011 年从 Vell 中分离得到的天然生物碱 cernumidine。
