Al Lorenzo was the Starfleet chief of operations on Decos Prime in 2375. He had a curious interest in taking holophotos of himself sitting behind the desks of famous Starfleet captains. Usually, he would sneak into their offices, but the Dominion War made it difficult for him to get away. Among the photos in his collection included Lorenzo sitting behind the desks of such famous commanders as Robert DeSoto and Jean-Luc Picard.
Nog, working on behalf of Miles O'Brien, loaned the desk of Benjamin Sisko to Lorenzo when the chief required a new graviton stabilizer for the USS Defiant. In return, Al Lorenzo gave Nog an induction modulator, which could be traded to the USS Musashi for a phaser emitter. In turn, this could be traded to the USS Sentinel for the needed stabilizer. (DS9: "Treachery, Faith and the Great River")
This character was only mentioned in dialogue.