Synthesis and antifungal testing of 2,4,5,7,9-pentathiadecane 9,9-dioxide has established that the absence of oxygen atoms on S2 significantly attenuates fungitoxicity in accord with our earlier proposal. Attempts to convert that compound into dysoxysulfone led to the discovery of a novel oxidative conversion of unsymmetrical γ-sulfonyl disulfides into the corresponding symmetrical γ-sulfonyl disulfides.
Novel silica-induced controlled disproportionation of α-mercaptosulfones produces α-mercapto α′-sulfonyl sulfides. Its discovery and exploitation, as the heart of a new process – vault isomerization – permits the elaboration of a more efficient synthesis of a previously described synthetic precursor.