The printed name property can be used for this:
Briefing Room is a room. The printed name of Briefing Room is "Briefing Room: Midday".
This can also be changed during play, as in "ยง8.5. Change of properties with values" in the manual.
AFAIK, using an apostrophe for quotation marks will only work within a string. The printed name property allows you to treat the room name like a string, e.g. including conditions and text substitutions within the name.