De Laurentiis took to Twitter to respond to speculation linking the Serie A side with a number of players around Europe, including Paris Saint-Germain's Marco Verratti.
De Laurentiis said: "We are a friend of Paris Saint-Germain and Verratti is not for sale.
"The player's agent is trying to put pressure on Paris Saint-Germain in order to gain a pay rise, but we do not go along with these games.
"We are searching for the right reinforcements in attack. It may be Martinez or it may be another. Our manager Rafael Benitez will decide."
Benitez has had a busy start to his reign as Napoli manager and has already lost star striker Edinson Cavani to PSG.
One player linked with replacing Cavani is Brazilian Leandro Damiao, but Internacional president Giovanni Luigi says that they have not received an official offer for the player.
Speaking with Radio Gaucha, Luigi said: "Leandro Damiao is focused. There has been no contact in the last days.
"They talked about Napoli, but nothing official has come."