It doesn't quite work that way. Most applications that run on UNIX have a linux version. Simply put: no linux migration path == lost software business. Except in the case of legacy stuff written back in the 1980's.
Linux is a derivative of UNIX, like earlier flavors of UNIX were derivatives System V UNIX that became AIX, Solaris, and so on. The difference here is that there are POSIX standards nowadays which means, in practical terms, that porting your homegrown code to Linux is usually feasible. Often pretty close to painless.
There are some products that are OS specific. You would get a lot better answers if you told us what applications you have running now and what you want to do. A list like you asked for will get you nowhere.
Example: oracle works well on UNIXes and Linux. In fact, Oracle appliances like EXADATA machines run Linux - for other UNIX types.