S₂in Drug Synthesis

Two convenient methods for the preparation of S2 have been developed and a third, based on binaphthyl chemistry, Is delineated. Although S2 additions to acyclic 1,3-dienes afford 1,2-dlthlin Dlels-Alder adducts, cyclic 1,3-dienes give bicycllc trisulfides. A [3,3] sigmatropic rearrangement Initiated from an additional S2 addition to the Diels-Alder adduct produced with cyclic dienes is proposed to account for the latter result. S2 also adds to strained olefins. However, it does not participate in the “ene” type reactions that plague singlet oxygen chemistry. Several of the 1,2-dithiln adducts, prepared from S2 additions, have been found to have antimicrobial properties, and more importantly, some also to Inhibit the in vitro HIV infection of H9 type tissue cells.