Pattern - using a word list?

I am trying to return certain letters to lowercase after using 'Title Caps'
i thought the easiest way would be to just use a list but i can't seem to create the right pattern, i've tried the following:

(And|Or|Of)
And|Or|Of
etc...

if i type one word on it's own (And) the method matches and returns 'A' to lowercase.

Have you tried the List replace method?