Pinout Rj45 a Db9

Hello, I have a question from a client.

“We already got the radios to link to each other. To transmit data through the serial ports, we need the pinout to build the cables from RJ45 to DB9 since our communication is serial.”

We do not have the adapter in stock and we need to solve it urgently

Could you send me the pinout?

Thank you very much