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Updated: Aug 22, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Multistep parallel synthesis of substituted 5-aminobenzimidazoles in solution phase
Li Li1, Gang Liu, Zhanguo Wang
1Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, P. R. China.
Abstract:
An efficient solution-phase parallel synthesis of multisubstituted 5-aminobenzimidazoles is described. The two fluorine atoms of 1,5-difluoro-2,4-dinitrobenzene (DFDNB) are sequentially and quantitatively replaced by nucleophiles. Simultaneous reduction of aromatic m-dinitro groups by Pd-C/HCOONH(4) results in 2,4,5-benzenetriamines, which are continuously condensed with aldehydes to successfully construct the benzimidazole ring without additional oxidants. The free aromatic amino group is further modified by anhydrides, isocyanates, isothiocyanates, and sulfonyl chlorides. All the reactions involved here are highly effective in giving the desired products at room temperature. Four diversity points are introduced in the final products.
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