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[摘要]:This paper explores the role of a hindered cyclic sulfamidate derived from alpha-methylisoserine as an electrophile in a nucleophilic displacement reaction with nitrogen-containing aromatic heterocycles. Several imidazoles and pyrazole were tested as nucleophiles in the absence of an additional base to give the corresponding ring-opening compounds: We show that the process takes place by inversion of the configuration of the quaternary electrophilic center, retaining the enantiomeric excess of the starting sulfamidate. This reaction opens the way to obtain important quaternary imidazole derivatives such as an innovative type of bis-amino add related to histidinoalanine and a novel alpha,alpha-disubstituted beta-amino acid(beta(2,2)-amino acid) |
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