A new synthesis of 4H-1,4-benzothiazine derivatives based on ring closure of EWG-stabilized (2-isocyanophenylthio)methyl anions
2-Cyano(phenylsulfinyl-, p-nitrophenyl-, or o-nitrophenyl-)methylthiophenyl isocyanides were synthesized from 2-aminobenzenethiols and were shown to undergo ring closure to 2,4-disubstituted 4H-1,4-benzothiazine derivatives by deprotonation of the hydroge