OCorrected for statistical factors. CDSCN. CAt 25 OC in MeOH. KOMs values have been calculated from equilibrium data referring to the attachment of MeO-to the corresponding thio- pyrylium cations. dAt 25" C. eReference 6.'At 100 OC.# Reference 7. hReference 5. interactions between the methoxy group and the ring sulfur atom, might depend only to a limited extent on the intrinsic stability of the heterocyclic systems. This prompted us to ...