The Pictet-Spengler Reaction on L-Histidine. Preparation of Conformationally Restricted (+)-Pilocarpine Analogs.
作者:M. del Mar Sánchez-Sánchez、L. M. Tel-Alberdi、M. Jesus Rioseras、M. del Rosario Rico-Ferreira、F. Bermejo-González
DOI:10.1246/bcsj.66.191
日期:——
The total regioselective synthesis of the rigid (+)-pilocarpine analogs 4—6 starting from L-histidine is described. The Pictet-Spengler condensation is used to prepare the tetrahydroimidazopyridine moiety present in the structure of these tricyclic derivatives.
作者:Raffael C. Wende、Alexander Seitz、Dominik Niedek、Sören M. M. Schuler、Christine Hofmann、Jonathan Becker、Peter R. Schreiner
DOI:10.1002/anie.201509863
日期:2016.2.18
report the development of the first enantioselective Dakin–West reaction, yielding α‐acetamido methylketones with up to 58 % ee with good yields. Two of the obtained products were recrystallized once to achieve up to 84 % ee. The employed methylimidazole‐containing oligopeptides catalyze both the acetylation of the azlactone intermediate and the terminal enantioselective decarboxylative protonation. We