Synthesis and antiviral activity of bis-spirocyclic derivatives of rhodanine

Bis-spiro heterocycles containing spiro units at the 1,3-positions of the pyrrolizidine (isothiapyrrolizidine) moiety were synthesized by the reaction of unstabilized azomethine ylides, which were generated in situ from isatin and proline (isothiaproline), with hetarylidene-substituted rhodanines. Quantum chemical calculations of potential energy surface sections and descriptors controlling the regioselectivity of cycloaddition were carried out. For a number of compounds in vitro activity against the influenza virus A/California/07/09 (H1N1)pdm2009 was experimentally established.