^^basicaly all kages not edoed, alive or used the reaper death seal.
jiraya - Couldn't.
kisame - Couldn't.
konan - Probably not worth it in Kabuto's eyes.
orochimaru - Nope.
the rest of the sound 4, despite them being wusses. they did shin for gods sake! - No way.
danzo - Couldn't.
all the other people who got mangekyo sharingan (itachi mentions them in chapter 386)
free to add more