Arduino sketches are written in C, not ladder logic - things like the Ardbox linked above have some PLC-like features, but they are still just programmed with C like any other Arduino, and at their core, they're just a standard AVR microcontroller with some industrial grade hardware around it.
There may well be tools to generate arduino-C from ladder logic, but I'm not aware of any. That said, ladder diagrams are a very limiting way to program anything.