is the 23.7-inch LG UltraFine 4K Display compatible with mac pro late 2013

If yours is a genuine Thunderbolt Display, you can connect it using the Apple ThunderBolt-3 <-> thunderbolt-2 adapter and a ThunderBolt-2 cable from the Mac.

This adapter supports ONLY genuine ThunderBolt displays, and no other display protocols. So if you have a later model that has a displayport or USB interface of any description, it will not work with this adapter.