Hankuk University of Foreign Studies 3 articles published in JoVE Chemistry Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions Yeongjin Lee1, Huimyoung Byeon1, Hyun-Joon Ha2, Jung Woon Yang1 1Department of Energy Science, Sungkyunkwan University, 2Department of Chemistry, Hankuk University of Foreign Studies Contiguous bisaziridines containing non-activated and activated aziridines were synthesized by asymmetric organocatalytic aziridinations and then subjected to chemoselective ring-opening reactions under acidic or basic conditions. The non-activated aziridine ring opens with less reactive nucleophiles under acidic conditions, whereas the activated aziridine ring opens with more reactive nucleophiles under basic conditions. Chemistry Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine Nikhil Srivastava1, Hyun-Joon Ha1 1Department of Chemistry, Hankuk University of Foreign Studies In this study, we prepare both enantiomers of aziridine-2-carboxylate, which are used in the asymmetric synthesis of alkaloids, including biemamide B and D, and (-)-epiallo-isomuscarine. Chemistry Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles Nagendra Nath Yadav1, Hyun-Joon Ha2 1Department of Chemistry, North Eastern Regional Institute of Science and Technology, 2Department of Chemistry, Hankuk University of Foreign Studies Bicyclic aziridinium ions such as 1-azoniabicyclo[4.1.0]heptane tosylate were generated from 2-[4-tolenesulfonyloxybutyl]aziridine, which was utilized for the preparation of substituted piperidines and azepanes via regio- and stereospecific ring-expansion with various nucleophiles. This highly efficient protocol allowed us to prepare diverse azaheterocycles including natural products such as fagomine, febrifugine analogue and balanol.
