RegEx (yeah, again) sigh

I am createing a pattern that looks like this

(?<!\B)(apropos(1)|whatis(1)|groff(1)|man.conf(5))\b

the purpose is to fine any/all occurances of the strings

apropos(1)
whatis(1)
groff(1)
man.conf(5)

the above obviously won’t work due to the ()
so I changed it to

(?<!\B)(apropos\(1\)|whatis\(1\)|groff\(1\)|man.conf\(5\))\b

and it still does not work… any ideas?

FYI… I have another pattern

(?<!\B)(NAME|SYNOPSIS|DESCRIPTION|MANUAL SECTIONS|OPTIONS|CAT PAGES|HTML PAGES|SEARCH PATH FOR MANUAL PAGES|ENVIRONMENT|BUGS|TIPS|AUTHOR|SEE ALSO)\b

that DOES work, the only diff is the ()

seems JUST that works