On his way to Risa for an extended vacation in late 2371, he disappeared and was replaced with a Changeling infiltrator. Starfleet Security believed the real Krajensky had been kidnapped or possibly killed. (DS9: "The Adversary")
Krajensky, like his Changeling counterpart. was played by Lawrence Pressman.
According to the script, Krajensky was pronounced as "kra-JEN-skee". Furthermore, in the script, he is described as a "...skilled career politician." 
The short story A Gutted World gives him the first name Theodore.