Abstract:

Our research group is interested in the development of new synthetic methodologies for the rapid generation of chemical libraries with high molecular diversity and complexity. During the last years we have been exploring the potential of the domino cascade reactions, which are a combination of multiple transformations in a single process. Particularly Iminium ions are useful as versatile intermediates for such kind of reactions as they may serve as electrophiles in a diverse range of bond forming possibilities. Recently we generated a focused library of thiols to evaluate it bioactivity as enzyme inhibitors. We also expanded the diversity of this system and were able to generate bisthiazolidines I or bis-thiiranes II by Multicomponent Connection Reaction (MCR) using iminium ions. In the present work is aimed to synthesize bisthiazolidine B, substituted with H or CO2Et at 2 position, and with variations at the R2 position. To avoid double cyclization and to introduce variability at R2 position, we proposed a step-wise procedure using the thiazolidine-1 as a key intermediate, see Figure 2.