sell it for less
lol...jokes aside, hard to give you an answer without any details.
I assume this is a land + building held under corporation? Questions such as "Have you been taking CCA on the building?", "Have you been operating your business in the property", etc will affect your tax & options
TBH, capital gain is already taxed at a very favourable rate. If you have been taking CCA from the building, you might get dinged even more tax than just the capital gain amount. (i.e. recapture)
If the buyer absolutely refuses to buy the corporation as a whole, there is really not much tax saving option.