This is what I use. You could add shift @ players to it.
This is what you asked for, with support for Shadow.
#showtooltip
/cast [mod:shift,spec3,@player] [mod:ctrl,spec:3,@mouseover,help,nodead] Purify Disease; [mod:shift,@player] [mod:ctrl,@mouseover,help,nodead] Purify; [mod:ctrl,@mouseover,harm,nodead] [harm] Dispel Magic; [spec:3] Purify Disease; Purify