Hydrogen-bond-assisted topochemical synthesis of a multivalent zwitterionic tetramer via concomitant cross- and homo [2+2] photocycloadditions. Theoretical antiviral activity against SARS-CoV-2

Compound [(3-H(2)PA)(HCh)]center dot 2H(2)O (1) represents a novel example of an ionic co-crystal that undergoes regioselectively a triple photoreaction to form a rare multivalent tetramolecular zwitterion (2) with a pentacyclic ladderane-like core in high yield. Molecular docking and molecular dynamics show that this molecule can bind well to the interface between the spike protein of SARS-CoV-2 and the cell surface receptor ACE2 with which it forms a complex to facilitate infection. At the same time, it could theoretically decrease viral replication.