6H-THIAZINES-1,3 SUBSTITUEES EN POSITION 2 PAR UN GROUPEMENT LABILE, ELECTROPHILES AMBIDENTS

Article abstract of DOI:10.1016/S0040-4039(00)94516-7

Substitution by H₂O in the presence of HCl and by NH(CH₃)₂ occurs at position 2 of 5-acetyl-2-benzylthio-6H-1,3-thiazine without ring opening (in the first step for the amine).Substitution by the softer anion derived from diethylmalonate (and most likely HS^-) occurs at position 6 with ring-opening.Subsequent cyclisations give the corresponding thiocarbonyl compounds.All these reactions are accompanied by elimination of the labile benzylthio group.