Cationic dyestuffs of the formula ##STR1## WHEREIN A and B denote aromatic-carbocyclic or aromatic-heterocyclic radicals,D denotes the groups --O--R.sub.2, ##STR2## R denotes hydrogen, alkyl, aralkyl, alkenyl, alkoxy or aryl, X denotes a bridge member andAn.sup.(.sup.-) denotes an anion,Are suitable for dyeing and printing of natural and synthetic materials, particularly of polyacrylonitrile, copolymers of acrylonitrile with other vinyl compounds, of acid modified polyesters and acid modified polyamides.