Negri was at Rangers when the Brighton midfielder was coming through at Ibrox.
He told Radio Sportiva: "I know Gilmour very well. He went through the whole process at Rangers, unfortunately they were in difficulty. Chelsea offered a great sum for the boy, Rangers had to get rid of him, with him they could have created a midfield for the future.
"He was lucky enough to meet (Roberto) De Zerbi (at Brighton) who gave him confidence and knowledge, I see him very well in Napoli. He is a pure midfielder, a playmaker, he plays in front of the defence, he passes out when you want to start from deep, he always shows up, very good technically. He doesn't have great dynamism or goals but he is a boy who in my opinion is very suitable: he is a Jorginho who can do very well with (Antonio) Conte."
Napoli are also being linked with Manchester United midfielder Scott McTominay. Negri added: "He is much more dynamic, he is a box to box, he covers much more of the field, he also skips the opponent and looks more into the opponent's area.
"Gilmour is more of a (Andrea) Pirlo, they are different as players but the Scots are really throwing out some excellent talents."