HETEROCYCLES, cilt.83, sa.9, ss.2091-2114, 2011 (SCI-Expanded)
Highly substituted bicyclic thiohydantoins fused to pyrrolidines were prepared from aminocarbo-N-thioylpyrrolidines derived from alpha-amino acid esters via imine azomethine ylide 1,3-dipolar cycloadditions and subsequent reaction with aroylisothiocyanates. Aminocarbo-N-thioylpyrrolidines efficiently undergo cyclisation in the presence of sodium methoxide to form bicyclic N-substituted thiohydantoins with concomitant cleavage of the N-acyl group in good to excellent yield. And also some interesting both regiospecific and stereospecific rearrangement to the bicyclic fused thiocarbamoil pyrrolidine and bicyclic thiohydantoin were observed.